2004-11-22 Assigned to MICRON TECHNOLOGY, INC. reassignment MICRON TECHNOLOGY, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: RERICHA, WILLIAM T., CHANCE, RANDAL W., SANDHU, GURTEJ S.
Alignment tolerances between narrow mask lines, for forming interconnects in the array region of an integrated circuit, and wider mask lines, for forming interconnects in the periphery of the integrated circuit, are increased. The narrow mask lines are formed by pitch multiplication and the wider mask lines are formed by photolithography. The wider mask lines and are aligned so that one side of those lines is flush with or inset from a corresponding side of the narrow lines. Being wider, the opposite sides of the wider mask lines protrude beyond the corresponding opposite sides of the narrow mask lines. The wider mask lines are formed in negative photoresist having a height less than the height of the narrow mask lines. Advantageously, the narrow mask lines can prevent expansion of the mask lines in one direction, thus increasing alignment tolerances in that direction. In the other direction, use of photolithography and a shadowing effect caused by the relative heights of the photoresist and the narrow mask lines causes the wider mask lines to be formed with a rounded corner, thus increasing alignment tolerances in that direction by increasing the distance to a neighboring narrow mask line.
This application is related to the following: U.S. patent application Ser. No. ______ to Abatchev et al., filed Aug. 31, 2004, entitled Critical Dimension Control, Attorney Docket No. MICRON.286A (Micron Ref. No. 03-1348.00/US); U.S. patent application Ser. No. ______ to Abatchev et al., filed Sep. 1, 2004, entitled Mask Material Conversion, Attorney Docket No. MICRON.293A (Micron Ref. No. 03-1435.00/US); U.S. patent application Ser. No. ______ to Abatchev et al., filed Sep. 2, 2004, entitled Method for Integrated Circuit Fabrication Using Pitch Multiplication, Attorney Docket No. MICRON.294A (Micron Ref. No. 03-1446.00/US); and U.S. patent application Ser. No. ______ to Tran et al., filed Aug. 31, 2004, entitled Methods for Increasing Photo-Alignment Margins, Attorney Docket No. MICRON.295A (Micron Ref. No. 04-0068.00/US).
This invention relates generally to integrated circuit fabrication and, more particularly, to masking techniques.
As a consequence of many factors, including demand for increased portability, computing power, memory capacity and energy efficiency in modern electronics, integrated circuits are continuously being reduced in size. To facilitate this size reduction, the sizes of the constituent features, such as electrical devices and interconnect line widths, that form the integrated circuits are also constantly being decreased.
The trend of decreasing feature size is evident, for example, in memory circuits or devices such as dynamic random access memories (DRAMs), static random access memories (SRAMs), ferroelectric (FE) memories, etc. To take one example, DRAM typically comprises millions of identical circuit elements, known as memory cells. In its most general form, a memory cell typically consists of two electrical devices: a storage capacitor and an access field effect transistor. Each memory cell is an addressable location that can store one bit (binary digit) of data. A bit can be written to a cell through the transistor and read by sensing charge on the storage electrode from the reference electrode side. By decreasing the sizes of constituent electrical devices and the conducting lines that access them, the sizes of the memory devices incorporating these features can be decreased. Additionally, storage capacities can be increased by fitting more memory cells into the memory devices.
The continual reduction in feature sizes places ever greater demands on techniques used to form the features. For example, photolithography is commonly used to pattern features, such as conductive lines, on a substrate. The concept of pitch can be used to describe the size of these features. Pitch is defined as the distance between an identical point in two neighboring features. These features are typically defined by spaces between adjacent features, which are typically filled by a material, such as an insulator. As a result, pitch can be viewed as the sum of the width of a feature and of the width of the space separating that feature from a neighboring feature. Due to factors such as optics and light or radiation wavelength, however, photolithography techniques each have a minimum pitch below which a particular photolithographic technique cannot reliably form features. Thus, the minimum pitch of a photolithographic technique can limit feature size reduction.
"Pitch doubling" is one method proposed for extending the capabilities of photolithographic techniques beyond their minimum pitch. Such a method is illustrated in FIGS. 1A-1F and described in U.S. Pat. No. 5,328,810, issued to Lowrey et al., the entire disclosure of which is incorporated herein by reference. With reference to FIG. 1A, photolithography is first used to form a pattern of lines 10 in a photoresist layer overlying a layer 20 of an expendable material and a substrate 30. As shown in FIG. 1B, the pattern is then transferred by an etch step (preferably anisotropic) to the layer 20, forming placeholders, or mandrels, 40. The photoresist lines 10 can be stripped and the mandrels 40 can be isotropically etched to increase the distance between neighboring mandrels 40, as shown in FIG. 1C. A layer 50 of material is subsequently deposited over the mandrels 40, as shown in FIG. 1D. Spacers 60, i.e., material extending or originally formed extending from sidewalls of another material, are then formed on the sides of the mandrels 40 by preferentially etching the spacer material from the horizontal surfaces 70 and 80 in a directional spacer etch, as shown in FIG. 1E. The remaining mandrels 40 are then removed, leaving behind the freestanding spacers 60, which together act as an etch mask for patterning underlying layers, as shown in FIG. 1F. Thus, where a given pitch formerly included a pattern defining one feature and one space, the same width now includes two features and two spaces defined by the spacers 60. As a result, the smallest feature size possible with a photolithographic technique is effectively decreased.
It will be appreciated that while the pitch is actually halved in the example above, this reduction in pitch is conventionally referred to as pitch "doubling," or, more generally, pitch "multiplication." That is, conventionally "multiplication" of pitch by a certain factor actually involves reducing the pitch by that factor. The conventional terminology is retained herein.
The critical dimension of a mask scheme or circuit design is the scheme's minimum feature dimension. Due to factors such as geometric complexity and different requirements for critical dimensions in different parts of an integrated circuit, typically not all features of the integrated circuit will be pitch multiplied. Consequently, pitch multiplied features will often need to be connected to or otherwise aligned with respect to non-pitch multiplied features in some part of the integrated circuit. Because these non-pitch multiplied features generally have larger critical dimensions than the pitch multiplied features, the margin of error for aligning the non-pitch multiplied features to contact the pitch multiplied features can be small. Moreover, because the critical dimensions of pitch-multiplied lines may be near the resolution and/or overlay limits of many photolithographic techniques, shorting neighboring pitch multiplied features is an ever-present possibility. Such shorts can undesirably cause the integrated circuit to malfunction.
Accordingly, there is a need for methods which allow increased margins of error for forming contacts between features of different sizes, especially for forming contacts between pitch multiplied and non-pitch multiplied features.
According to one aspect of the invention, a method is provided for forming an integrated circuit. The method comprises providing a substrate with an overlying temporary layer and a photodefinable layer overlying the temporary layer. A pattern is formed in the photodefinable layer and transferred to the temporary layer to form a plurality of placeholders in the temporary layer. A blanket layer of spacer material is then deposited over the plurality of placeholders. The spacer material is selectively removed from horizontal surfaces. The placeholders are selectively removed relative to the spacer material to form a plurality of spacer loops. The spacer loops are etched to form a pattern of separated spacers. An other photodefinable layer is formed around and on the same level as the separated spacers. Interconnects are patterned in the other photodefinable layer. The interconnects are wider than the spacers and contact the spacers and are aligned with one long side of the interconnects inset from or collinear with a corresponding long side of the spacers.
According to another aspect of the invention, a method is provided for semiconductor fabrication. The method comprises providing a substrate and forming an elongated spacer over the substrate by pitch multiplication. A photoresist line is then formed. The photoresist line is in contact with an end of the spacer in a contact region. The spacer forms a boundary for only two faces of the photoresist line in the contact region.
According to yet another aspect of the invention, a process is provided for fabricating an integrated circuit. The process comprises forming a first plurality of mask lines and forming a photodefinable layer around the mask lines. The photodefinable layer has a thickness less than a height of the mask lines. A plurality of features is patterned in the photodefinable layer.
According to another aspect of the invention, a partially fabricated integrated circuit is provided. The partially fabricated integrated circuit comprises a substrate and a first plurality of mask lines overlying the substrate. A photodefinable layer contacts the mask lines. The photodefinable layer has a thickness less than a height of the mask lines.
According to yet another aspect of the invention, an integrated circuit is provided. The integrated circuit comprises a plurality of interconnects, each having a first portion with a first width in an array region and a second portion with a second width in a periphery region. The second width is larger than the first width. An end of each of the second interconnect portions contacts an end of each of the first interconnect portions. One side of each of the second interconnect portions, extending along a length of one of the second interconnect portions, is substantially collinear with or inset from one side of each of the first interconnect portions, extending along a length of one of the first interconnect portions.
According to another aspect of the invention, an integrated circuit is provided. The integrated circuit comprises a plurality of interconnects each having a first portion and a second portion. The first portion of the interconnects are substantially parallel to each other between first and second spaced planes extending perpendicular to the lines. In addition, the first portion and the second portion contact in an overlap region. Only one corner of the second portion protrudes beyond a side of the first portion in the overlap region.
FIG. 21 is a schematic, top plan view of the partially formed integrated circuit of FIG. 20 after forming conductive interconnects in the substrate, in accordance with preferred embodiments of the invention.
Typically, separately defined features contacting lines are nominally centered perfectly on the lines to maximize the separation of the features from neighboring pitch-multiplied lines. FIGS. 2A and 2B shows such an idealized alignment of pitch multiplied lines 91 and non-pitch multiplied lines 92. FIG. 2A shows an arrangement in which every line 91 is contacted on the same side with a line 92 and FIG. 2B shows an arrangement in which lines 92 contact the lines 91 on alternating sides.
Various types of misalignments can occur in the overlap region 93 in which the lines 91 and 92 contact, however. For example, the lines 92 may all be misaligned in one direction. Because the lines 92 are wider than the space separating the lines 91, a single line 92 can short two lines 91 if the misalignment is severe. Another form of misalignment can occur when a line 92 is skewed in one direction, relative to other lines 92. This can also cause a short if neighboring lines 92 contact. In reality, all these forms of misaligmuents can occur concurrently. In addition, because the lines 91 are also formed with a certain margin of error in size and location, any misalignment of the lines 92 may be exacerbated by misalignments or deviations in size of the lines 91. Thus, to minimize the possibility of shorts or otherwise sub-optimal contacts, the tolerances for misalignments of the lines 92 and 91 are preferably large. For lines 92 and 94 each having a given width, the distances 94 between each line 92 and each line 91 and the distances 95 between neighboring lines 92 are preferably each maximized to maximize tolerances. More preferably, both of the distances 94 and 95 are maximized. It will be appreciated that the same principles apply when the features are contacts, contact pads or other features that are to be kept separate.
Reference will now be made to the Figures, wherein like numerals refer to like parts throughout. It will be appreciated that the Figures are not necessarily drawn to scale.
With reference initially to FIGS. 3A and 3B, preferred embodiments of the invention advantageously allow for increased misalignment tolerances. Preferably, a first feature, such as a line 91, is formed in a first mask layer and a second feature, such as a line 92, is overlaid the first feature by patterning a second masking layer. Rather than center the second feature on the first feature, the second feature is aligned so that only one of its sides 92 a extends beyond a corresponding side 91 a of the first feature, as illustrated in FIG. 3A. The other side 92 b is shown inset from the corresponding side 91 b of the first feature. Thus, only part of the end of the smaller first line 91 is overlapped with the end of the wider second line 92 and only one corner of the line 92 protrudes beyond a side of the line 91. In other preferred embodiments, as illustrated in FIG. 3B, side 92 b preferably is positioned substantially flush or collinear with side 91 b, while side 92 a is positioned beyond side 91 a. It will be appreciated that the lines 92 can also contact the lines 91 on alternating sides, as shown in FIGS. 3C and 3D. Moreover, because the lines 92 alternate on any given side of the lines 91, the corners 96 can protrude beyond either side 91 a or 91 b or some corners 96 can protrude beyond the side 91 a and others beyond the side 91 b, since concerns of two neighboring corners 96 shorting are minimized by the alternating arrangement.
Thus, preferably only one corner 96 of the wider second feature protrudes substantially beyond the narrow first feature. As discussed below, the protruding corner 96 can be formed rounded. By utilizing this rounding, the distance, e.g., distance 94, between neighboring features, e.g., the lines 91 and 92, in the overlap region, e.g., region 93, can be increased relative to lines 92 without rounding.
Moreover, as also discussed below, the second feature is preferably formed in photoresist by photolithography. The photoresist is preferably formed below the vertical height of the first feature, as illustrated in FIG. 3E for lines 91 and 92, the lines 91 having a height 97. As such, the first features, such as the lines 91, act as walls that permit the second features, such as the lines 92, to grow, if at all, in only one direction. Thus, by limiting the potential growth of the second features and by geometrically positioning the mask features to maximize the distance between neighboring features, misalignment tolerances can be increased.
Advantageously, any misalignments can be weighted in one direction, e.g., in the direction of the sides 91 b, while still maintaining an adequate distance 94 between lines 92 and 91. Moreover, the photoresist can be overdeveloped to narrow the second features to further minimize the possibility of shorting. It will be appreciated that the overdevelopment can include any process which reduces the critical dimension of the lines 92. For example, the overdevelopment can include extending the development period and/or performing an additional treatment or technique to controllably remove resist, e.g., partially exposed resist. For example, the overdevelopment can remove resist in the exposure threshold or "gray" area between the area fully exposed to radiation transmitted through the reticle and lens system and the area that is "dark" or exposed to a light intensisty below the exposure threshold for the resist.
While not limited by theory, three effects have been found to be advantageously present in the preferred embodiments. It will be appreciated that each of these effects are independently advantageous and are not each necessarily present in all embodiments. Nevertheless, all three effects can be found in particularly advantageous embodiments.
Preferably, the first mask features, such as the lines 91, are first formed and then the second mask features, such as the lines 92, are overlaid the first features. The second features are preferably patterned in photoresist that overlaps the first features. It will be appreciated that the photoresist is typically patterned by being exposed to radiation through a reticle and then developed. In the case of negative photoresist, radiation, e.g., light, is focused on parts of the photoresist which are to be retained, e.g., on the areas where the lines 92 are to be formed. Typically, the radiation activates a photosensitive compound, e.g., a photo-induced acid generator (PAG), which decreases the solubility of the photoresist, e.g., by causing it to polymerize. Such photoactivated chemicals, however, can diffuse, thereby causing the lines 92 to expand to areas that are not irradiated. In addition to decreasing the precision with which the lines 92 are formed, this diffusion can also cause the lines 92 to expand, thereby decreasing alignment tolerances by decreasing distances 94 between the lines 91 and 92.
In the preferred embodiments, the photoresist is preferably formed at a level below the top of the first mask features, such as the lines 91. The photoresist is then patterned to form the second features. Advantageously, in this arrangement, the first mask features act as a wall, only allowing diffusion of photogenerated acid from PAG's in a direction away from those first mask features. Thus, the misalignment tolerance in the region 93 can be increased by an amount approximately equal to the amount that the photogenerated acids would have otherwise diffused to expand the lines 92. Since diffusion can only occur in one direction, the risk of shorting from diffusion is effectively halved in the overlap region.
In addition, due to various factors, including diffusion of photogenerated acids and diffraction of radiation, photolithography will form corners that are rounded. Thus, by aligning features such as the lines 91 and 92 so that each narrow line 91 is closest to a rounded corner of a neighboring line 92, the rounding effect can be used to increase the distance between the wider lines 92 and adjacent narrower lines 91. This advantageously also increases misalignment margins by increasing corner-to-corner distances, such as the distance 94.
Also, while the preferred embodiments may be applied using any photodefinable material, including positive or negative photoresist, negative photoresist is utilized in particularly advantageous embodiments. Advantageously, by using negative photoresist to form the lines 92 and forming that photoresist below the level of the second features, such as the lines 91, the rounding effect can be increased. It will be appreciated that light reaching the photoresist between lines 91 is attenuated due to a shadowing affect caused by the presence of the taller lines 91. Moreover, this attenuation will increase with increasing distance down the lines 91 away from the ends of the lines 91. Advantageously, because the formation of the lines 92 depends upon light hitting the negative photoresist, the attenuation further rounds off and narrows the width of the lines 92 between lines 91. As a result, the distances between the wider lines 92 and the neighboring narrower lines 91 can be further increased, thereby further increasing misalignment margins.
More preferably, a combination of positive and negative photoresist is used, with the positive photoresist used in forming (preferably via a process utilizing spacers) the lines 91 and the negative photoresist using in forming the lines 92. The negative photoresist advantageously increases the rounding discussed above, while the positive photoresist advantageously allows a higher resolution relative to the negative photoresist.
FIG. 4A shows a top view of an integrated circuit 100, which is preferably a memory chip. A central region 102, the "array," is surrounded by a peripheral region 104, the "periphery." It will be appreciated that, in a fully formed integrated circuit 100, the array 102 will typically be densely populated with conducting lines and electrical devices such as transistors and capacitors. In a memory device, the electrical devices form a plurality of memory cells, which are typically arranged in a regular pattern, such as rows. Desirably, pitch multiplication can be used to form features such as rows/columns of transistors, capacitors or interconnects in the array 102, as discussed below. On the other hand, the periphery 104 typically comprises features larger than those in the array 102. Conventional photolithography, rather than pitch multiplication, is preferably used to pattern features, such as logic circuitry, in the periphery 104, because the geometric complexity of logic circuits located in the periphery 104 makes using pitch multiplication difficult, whereas the regular grid typical of memory array patterns is conducive to pitch multiplication. In addition, some devices in the periphery require larger geometries due to electrical constraints, thereby making pitch multiplication less advantageous than conventional photolithography for such devices. It will be appreciated that the periphery 104 and the array 102 are not draw to scale and their relative positions may vary from that depicted.
With reference to FIG. 4B, a partially formed integrated circuit 100 is provided. A substrate 110 is provided below various masking layers 120-160. The layers 120-160 will be etched to form a mask for patterning the substrate 110 to form various features, as discussed below.
The materials for the layers 120-160 overlying the substrate 110 are preferably chosen based upon consideration of the chemistry and process conditions for the various pattern forming and pattern transferring steps discussed herein. Because the layers between a topmost selectively definable layer 120, which preferably is definable by a lithographic process, and the substrate 110 will preferably function to transfer a pattern derived from the selectively definable layer 120 to the substrate 110, the layers between the selectively definable layer 120 and the substrate 110 are preferably chosen so that they can be selectively etched relative to other exposed materials. It will be appreciated that a material is considered selectively, or preferentially, etched when the etch rate for that material is at least about 5 times greater, preferably about 10 times greater and, most preferably, at least about 40 times greater than that for surrounding materials.
In the illustrated embodiment, the selectively definable layer 120 overlies a first hard mask, or etch stop, layer 130, which overlies a temporary layer 140, which overlies a second hard mask, or etch stop, layer 150, which overlies an additional mask layer 160, which overlies the substrate 110 to be processed (e.g., etched) through a mask. Preferably, the mask through which the substrate 110 is processed is formed in the second hard mask layer 150 or in the additional mask layer 160.
It will be understood that in common methods of transferring patterns, both the mask and the underlying substrate are exposed to an etchant, which preferentially etches away the substrate material. The etchants, however, also wear away the mask materials, albeit at a slower rate. Thus, over the course of transferring a pattern, the mask can be worn away by the etchant before the pattern transfer is complete. These difficulties are exacerbated where the substrate 110 comprises multiple different materials to be etched. In such cases, the additional mask layer 160, which preferably comprises a thick layer of amorphous carbon, is desirable to prevent the mask pattern from being worn away before the pattern transfer is complete. The illustrated embodiment shows the use of the additional mask layer 160.
It will also be understood, however, that because the various layers are chosen based upon the requirements of chemistry and process conditions, one or more of the layers can be omitted in some embodiments. For example, the additional mask layer 160 can be omitted in embodiments where the substrate 110 is relatively simple, e.g., where the substrate 110 is a single layer of material and where the depth of the etch is moderate. In such cases, the second hard mask layer 150 may be a sufficient mask for transferring a pattern to the substrate 110. Similarly, for a particularly simple substrate 110, the various other layers, such the second hard mask layer 150 itself, may be omitted and overlying mask layers may be sufficient for the desired pattern transfer. The illustrated sequence of layers, however, is particularly advantageous for transferring patterns to difficult to etch substrates, such as a substrate 110 comprising multiple materials or multiple layers of materials, or for forming small and high aspect ratio features.
With reference to FIG. 2, the selectively definable layer 120 is preferably formed of a photoresist, including any photoresist known in the art. For example, the photoresist can be any photoresist compatible with 13.7 nm, 157 nm, 193 nm, 248 nm or 365 nm wavelength sytems, 193 nm wavelength immersion systems or electron beam lithographic systems. Examples of preferred photoresist materials include argon fluoride (ArF) sensitive photoresist, i.e., photoresist suitable for use with an ArF light source, and krypton fluoride (KrF) sensitive photoresist, i.e., photoresist suitable for use with a KrF light source. ArF photoresists are preferably used with photolithography systems utilizing relatively short wavelength light, e.g., 193 nm. KrF photoresists are preferably used with longer wavelength photolithography systems, such as 248 nm systems. In other embodiments, the layer 120 and any subsequent resist layers can be formed of a resist that can be patterned by nano-imprint lithography, e.g., by using a mold or mechanical force to pattern the resist.
The material for the first hard mask layer 130 preferably comprises an inorganic material, and exemplary materials include silicon oxide (SiO2), silicon or a dielectric anti-reflective coating (DARC), such as a silicon-rich silicon oxynitride. In the illustrated embodiment, the first hard mask layer 130 is a dielectric anti-reflective coating (DARC). The temporary layer 140 is preferably formed of amorphous carbon, which offers very high etch selectivity relative to the preferred hard mask materials. More preferably, the amorphous carbon is a form of transparent carbon that is highly transparent to light and which offers further improvements for photo alignment by being transparent to wavelengths of light used for such alignment. Deposition techniques for forming a highly transparent carbon can be found in A. Helmbold, D. Meissner, Thin Solid Films, 283 (1996) 196-203, the entire disclosure of which is incorporated herein by reference.
Advantageously, using DARCs for the first hard mask layer 130 can be particularly advantageous for forming patterns having pitches near the resolution limits of a photolithographic technique. The DARCs can enhance resolution by minimizing light reflections, thus increasing the precision with which photolithography can define the edges of a pattern. Optionally, a bottom anti-reflective coating (BARC) (not shown) can similarly be used in addition to the first hard mask layer 130 to control light reflections.
The second hard mask layer 150 preferably comprises a dielectric anti-reflective coating (DARC) (e.g., a silicon oxynitride), silicon or aluminum oxide (Al2O3). A bottom anti-reflective coating (BARC) (not shown) can optionally be used to control light reflections. In addition, like the temporary layer 140, the additional mask layer 160 is preferably formed of amorphous carbon due to its excellent etch selectivity relative to many materials.
In addition to selecting appropriate materials for the various layers, the thicknesses of the layers 120-160 are preferably chosen depending upon compatibility with the etch chemistries and process conditions described herein. For example, when transferring a pattern from an overlying layer to an underlying layer by selectively etching the underlying layer, materials from both layers are removed to some degree. Thus, the upper layer is preferably thick enough so that it is not worn away over the course of the pattern transfer.
In the illustrated embodiment, the selectively definable layer 120 is a photodefinable layer preferably between about 50-300 nm thick and, more preferably, between about 200-250 nm thick. The first hard mask layer 130 is preferably between about 100-400 nm thick and, more preferably, between about 150-300 nm thick. The temporary layer 140 is preferably between about 100-200 nm thick and, more preferably, between about 120-150 nm thick. The second hard mask layer 150 is preferably between about 20-80 nm thick and, more preferably, about 50 nm thick and the additional mask layer 160 is preferably between about 200-500 nm thick and, more preferably, about 300 nm thick.
The various layers discussed herein can be formed by various methods known to those of skill in the art. For example, various vapor deposition processes, such as chemical vapor deposition, can be used to form hard mask layers. Preferably, a low temperature chemical vapor deposition process is used to deposit the hard mask layers or any other materials, e.g., spacer material, over the mask layer 160, where the mask layer 160 is formed of amorphous silicon. Such low temperature deposition processes advantageously prevent chemical or physical disruption of the amorphous carbon layer. Spin-on-coating processes can be used to form photodefinable layers. In addition, amorphous carbon layers can be formed by chemical vapor deposition using a hydrocarbon compound, or mixtures of such compounds, as carbon precursors. Exemplary precursors include propylene, propyne, propane, butane, butylene, butadiene and acetelyne. A suitable method for forming amorphous carbon layers is described in U.S. Pat. No. 6,573,030 B1, issued to Fairbairn et al. on Jun. 3, 2003, the entire disclosure of which is incorporated herein by reference. In addition, the amorphous carbon may be doped. A suitable method for forming doped amorphous carbon is described in U.S. patent application Ser. No. 10/652,174 to Yin et al., the entire disclosure of which is incorporated herein by reference.
In a first phase of methods in accordance with the preferred embodiments and with reference to FIGS. 4-11, a pattern of spacers is formed by pitch multiplication.
With reference to FIG. 5, a pattern comprising spaces or trenches 122 delimited by photodefinable material features 124 is formed in the photodefinable layer 120. The trenches 122 can be formed by, e.g., photolithography, in which the layer 120 is exposed to radiation through a reticle and then developed. After being developed, the remaining photodefinable material, photoresist in the illustrated embodiment, forms mask features such as the illustrated lines 124 (shown in cross-section only).
The pitch of the resulting lines 124 is equal to the sum of the width of a line 124 and the width of a neighboring space 122. To minimize the critical dimensions of features formed using this pattern of lines 124 and spaces 122, the pitch is preferably at or near the limits of the photolithographic technique used to pattern the photodefinable layer 120. For example, for photolithography utilizing 248 nm light, the pitch of the lines 124 can be about 100 nm. Thus, the pitch may be at the minimum pitch of the photolithographic technique and the spacer pattern discussed below can advantageously have a pitch below the minimum pitch of the photolithographic technique.
As shown in FIG. 6, the spaces 122 can optionally be widened or narrowed to a desired dimension. For example, the spacers 122 can be widened by etching the photoresist lines 124, to form modified spaces 122 a and lines 124 a. The photoresist lines 124 are preferably etched using an isotropic etch, such as a sulfur oxide plasma, e.g., a plasma comprising SO2, O2, N2 and Ar. The extent of the etch is preferably selected so that the widths' of the lines 124 a are substantially equal to the desired spacing between the later-formed spacers 175, as will be appreciated from the discussion of FIGS. 9-11 below. Advantageously, this etch allows the lines 124 a to be narrower than would otherwise be possible using the photolithographic technique used to pattern the photodefinable layer 120. In addition, the etch can smooth the edges of the lines 124 a, thus improving the uniformity of those lines. In other embodiments, the spaces between the spaces 122 can be narrowed by expanding the lines 124 to a desired size. For example, additional material can be deposited over the lines 124 or the lines 124 can be chemically reacted to form a material having a larger volume to increase their size.
The pattern in the (modified) photodefinable layer 120 is preferably transferred to the temporary layer 140 to allow for deposition of a layer 170 of spacer material (FIG. 9). The temporary layer 140 is preferably formed of a material that can withstand the process conditions for spacer material deposition and etch, discussed below. In other embodiments where the deposition of spacer material is compatible with the photodefinable layer 120, the temporary layer 140 can be omitted and the spacer material can be deposited directly on the photo-defined features 124 or the modified photodefined features 124 a of the photodefinable layer 120 itself.
In the illustrated embodiment, in addition to having higher heat resistance than photoresist, the material forming the temporary layer 140 is preferably selected such that it can be selectively removed relative to the material for the spacers 175 (FIG. 10) and the underlying etch stop layer 150. As noted above, the layer 140 is preferably formed of amorphous carbon.
The pattern in the photodefinable layer 120 is preferably first transferred to the hard mask layer 130, as shown in FIG. 7. This transfer is preferably accomplished using an anisotropic etch, such as an etch using a fluorocarbon plasma, although a wet (isotropic) etch may also be suitable if the hard mask layer 130 is thin. Preferred fluorocarbon plasma etch chemistries include CF4, CFH3, CF2H2 and CF3H.
The pattern in the photodefinable layer 120 is then transferred to the temporary layer 140, as shown in FIG. 8, preferably using a SO2-containing plasma, e.g., a plasma containing SO2, O2 and Ar. Advantageously, the SO2-containing plasma can etch carbon of the preferred temporary layer 140 at a rate greater than 20 times and, more preferably, greater than 40 times the rate that the hard mask layer 130 is etched. A suitable SO2-containing plasma is described in U.S. patent application Ser. No. ______ to Abatchev et al., filed Aug. 31, 2004, entitled Critical Dimension Control, Attorney Docket No. MICRON.286A (Micron Ref. No. 03-1348.00/US), the entire disclosure of which is incorporate herein by reference. It will be appreciated that the SO2-containing plasma can simultaneously etch the temporary layer 140 and also remove the photodefinable layer 120. The resulting lines 124 b constitute the placeholders or mandrels along which a pattern of spacers 175 (FIG. 10) will be formed.
Next, as shown in FIG. 9, a layer 170 of spacer material is preferably blanket deposited conformally over exposed surfaces, including the hard mask layer 130, the hard mask 150 and the sidewalls of the temporary layer 140. Optionally, the hard mask layer 130 can be removed before depositing the layer 170. The spacer material can be any material that can act as a mask for transferring a pattern to the underlying substrate 110, or that otherwise can allow processing of underlying structures through the mask being formed. The spacer material preferably: 1) can be deposited with good step coverage; 2) can be deposited at a temperature compatible with the temporary layer 140; 3) can be selectively etched relative to the temporary layer 140 and any layer underlying the temporary layer 140. Preferred materials include silicon oxides and nitrides. The spacer material is preferably deposited by chemical vapor deposition or atomic layer deposition. The layer 170 is preferably deposited to a thickness of between about 20-60 nm and, more preferably, about 20-50 nm. Preferably, the step coverage is about 80% or greater and, more preferably, about 90% or greater.
As shown in FIG. 10, the spacer layer 170 is then subjected to an anisotropic etch to remove spacer material from horizontal surfaces 180 of the partially formed integrated circuit 100. Such an etch, also known as a spacer etch, can be performed using HBr/Cl plasma. The etch includes a physical component and preferably can also include a chemical component and can be, e.g., a reactive ion etch (RIE), such as a Cl2, HBr etch. Such an etch can be performed, for example, using a LAM TCP9400 flowing about 0-50 sccm Cl2 and about 0-200 sccm HBr at about 7-60 mTorr pressure with about 300-1000 W top power and about 50-250 W bottom power.
With reference to FIG. 11, the hard mask layer 130 (if still present) and the temporary layer 140 are next removed to leave freestanding spacers 175. The temporary layer 140 is selectively removed, preferably using a sulfur-containing plasma etch such as an etch using SO2.
Thus, pitch multiplication has been accomplished. In the illustrated embodiment, the pitch of the spacers 175 is roughly half that of the photoresist lines 124 and spaces 122 (FIG. 5) originally formed by photolithography. Advantageously, spacers 175 having a pitch of about 100 nm or less can be formed. It will be appreciated that because the spacers 175 are formed on the sidewalls of the features or lines 124 b, the spacers 175 generally follow the outline of the pattern of features or lines 124 a in the photodefinable layer 120 and, so, typically form a closed loop.
Next, in a second phase of methods according to the preferred embodiments, the loops formed by the spacers 175 are separated into individual lines. This separation is preferably accomplished by an etch that for each loop forms two separate lines of spacers 175 corresponding to two separate conductive paths in the substrate 110. It will be appreciated that more than two lines can be formed, if desired, by etching the spacers 175 at more than two locations.
To form the separate lines, a protective mask is preferably formed over parts of the lines to be retained and the exposed, unprotected parts of the spacer loops are then etched. The protective mask is then removed to leave a plurality of electrically separated lines.
With reference to FIG. 12, a protective material forming a second protective layer 300 is preferably deposited around and over the spacers 175 and the parts of the layers 150 and 160. The protective material is preferably a photodefinable material such as photoresist. Optionally, an anti-reflective coating (not shown) can be provided under the layer 300, e.g., directly above the substrate 110, to improve photolithography results. The photoresist and the anti-reflective coating can be deposited using various methods known in the art, including spin-on-coating processes.
With reference to FIG. 13, a protective mask 310 is subsequently patterned in the second protective layer 300, e.g., by photolithography, to protect desired parts of the underlying spacers 175 from a subsequent etch. To separate the spacers 175 of one loop into two separate lines, portions of the loops are exposed for etching in at least two separate locations. To simplify processing, the exposed portions of the loops are preferably the ends of the loops formed by the spacers 175, as illustrated.
In other embodiments, it will be appreciated that the protective layer 300 can be formed of any material that can be selectively removed, e.g., relative to the spacers 175, the layers 150-160 and the substrate 110. In those cases, the protective mask 310 can be formed in another material, e.g., photoresist, overlying the layer 300.
With reference to FIG. 14A, the exposed portions of the spacers 175 are etched away. Where the spacers 175 comprise silicon oxide or nitride, preferred etch chemistries include a fluorocarbon etch. After being etched, the spacers 175 no longer form a loop with a neighboring spacer 175. FIG. 14B shows a side view of the resulting structure, taken along the vertical plane 14B of FIG. 14A.
With reference to FIGS. 15A and 15B, the protective material is preferably selectively removed. For example, the partially formed integrated circuit 100 can be subjected to an ash process to remove the protective material. It will be appreciated that the spacers 175 are not attacked during this removal step and that the layer 160 is protected by the second hard mask layer 150. Thus, a plurality of individual mask lines 320 are formed. FIG. 15A shows a top plan view of the resultant structure and FIG. 15B shows a cross-sectional side view taken along the vertical plane 15B of FIG. 15A.
Next, in a third phase of methods according to the preferred embodiments, a second pattern is stitched or overlapped with the pattern of spacers 320. In the illustrated embodiments, the second pattern is overlaid on the spacers 320 to pattern features that will contact the features defined by the spacers 320. To form this second pattern, a photodefinable layer 400 is preferably formed around the spacers 320, as shown in FIG. 16. The photodefinable layer 400 preferably has a height below the level of the spacers 320. Preferably, the photodefinable layer 400 is formed of photoresist and, more preferably, negative photoresist.
The photoresist can be deposited to the desired height using a scan coating method, such as that commercially available from Tokyo Electron Limited (TEL) of Tokyo, Japan. In other embodiments, a relatively thick layer of photoresist can be deposited and then etched back to the desired height. Preferably, the etch back does not activate PAG's or otherwise detrimentally effect the photoresist for subsequent exposure and development steps. The photodefinable layer 400 is preferably about 80% or less and, more preferably, about 75-50% of the height of the spacers 320.
A pattern corresponding to line extensions or contacts to features to be defined by the spacers 320 is next formed in the photodefinable layer 400. It will be appreciated that the photodefinable layer 400 can be patterned using any photolithographic technique, including the same photolithographic technique used to pattern the photodefinable layer 120. Preferably, the photodefinable layer 400 is patterned using a higher resolution technique than the photodefinable layer 120. For example, where the photodefinable layer 120 is patterned using 248 nm photolithography to form features having a pitch of about 100 nm, the photodefinable layer 400 can be patterned using 193 nm photolithography to form features having a pitch of about 140 nm. Preferably, the photodefinable layer 400 is patterned using a lithographic technique that allows patterning with a pitch less than that of the spacers 320. For example, electron beam lithography, which has high resolution but relatively poor alignment capabilities, can be used to pattern the photodefinable layer 400.
With reference to FIGS. 17A and 17B, a pattern of features 410 is formed in the photodefinable layer 400. It will be appreciated that the features 410 can be used to pattern features of different sizes than the spacers 320, including landing pads, local interconnects, etc. As illustrated, the features 410 preferably overlap the pattern of spacers 320 to ultimately form interconnects that contact interconnects formed using the spacers 320. In the illustrate embodiment, the interconnects formed using the features 410 have a larger critical dimension than those formed using the spacers 320.
FIG. 17A shows a top plan view of the resulting structure, with features 410 and spacers 320. It will be appreciated that the shape of the features 410 correspond to the location of light reaching the photoresist layer 400 (FIG. 16), where the photoresist layer 400 comprises negative photoresist. Where the photoresist layer 400 comprises positive photoresist, light is directed to all areas of the partially fabricated integrated circuit 100, except for the location of the features 410. Due to the corner rounding phenomena discussed above, the shape of the features 410 in the reticle (not shown) can be rectangular, with sharp corners, while still advantageously forming rounded corners. More preferably, the reticle is shaped to ensure rounding of the corners, especially where positive photoresist is used.
In addition, the reticle can be positioned so that the features 410 align with one of their long sides 410 a inset from the corresponding long sides 320 a of the spacers 320 to ensure that the sides 410 a do not extend beyond the sides 320 a. Thus, while illustrated inset from the sides 320 a a certain distance, in other embodiments, due to the limitations of photolithography, the sides 410 a may be further inset from the sides 320 a or may be collinear with the sides 320 a. Preferably, however, a targeted or desired position of the sides 410 a is collinear with or slightly inset from the sides 320 a.
As known in the art, the photoresist is developed after being irradiated, leaving the pattern of features 410 shown. FIG. 17B shows a cross-sectional side view of the partially fabricated integrated circuit 100, taken along the vertical plane 17B of FIG. 17A.
With reference to FIG. 18, in some embodiments the features 410 may be larger than desired (solid line) or may be positioned beyond the sides 410 a. In such cases, the photoresist layer 400 can be overdeveloped to further narrow those features to a desired size (dotted line) and/or position.
The pattern of features 410 and spacers 320 can next be transferred to the additional mask layer 160. Preferably, the additional mask layer 160 comprises a material having good etch selectivity to the material(s) of the substrate 110, and vice versa, to allow for an effective transfer and later mask removal. To transfer to the pattern, the hard mask layer 150 overlying the additional mask layer 160 is first etched (FIG. 19). The hard mask layer 150 is preferably anisotropically etched, preferably using a fluorocarbon plasma. Alternatively, an isotropic etch may be used if the hard mask layer 150 is relatively thin. While not shown, it will be understood that in the array region 102, the hard mask 150 remains only directly under the spacers 320. The additional mask layer 160 is then anisotropically etched, preferably using a SO2-containing plasma, which can simultaneously remove the features 410. FIG. 20 shows a schematic side view of the resulting partially formed integrated circuit 100 in the region of overlap between the two patterns. The pattern in the additional mask layer 160 can then be transferred to the substrate 110. Given the disparate materials typically used for the additional mask layer 160 and the substrate 110 (e.g., amorphous carbon and silicon or silicon compounds, respectively), the pattern transfer can be readily accomplished using conventional etches appropriate for the material or materials of the substrate 110.
Preferably, the substrate 110 comprises a conductor suitable for acting as electrical interconnects between electrical devices. For example, the substrate comprises doped silicon or a metal layer, such as an aluminum or copper layer. Thus, the mask lines 320 and 410 can directly correspond to the desired placement of interconnects in the substrate 110. FIG. 21 shows a resulting structure, with interconnects 420 formed in the partially formed integrated circuit 100. In other embodiments, the substrate can be an insulator and the location of mask features can correspond to the desired location of insulators in an integrated circuit.
It will be appreciated that formation of contacts according to the preferred embodiments offers numerous advantages. For example, because the spacers 320 block photogenerated chemicals, such as acid from PAG's, from diffusing in one direction, the features 410 are prevented from growing in that direction in the region of contact with the spacers 320. Thus, the misalignment tolerance, especially in the direction in which diffusion is blocked, may be thought of as increasing by the amount that the features 410 would have otherwise expanded. In the other direction, the rounding of the corners, due partially to shadowing from the taller spacers extending above the second resist layer, also increases the misalignment tolerance by increasing the distance between the spacers 320 and the features 410. Moreover, given that diffusion is prevented in one direction, any misalignment can be weighted in that direction, since further expansion in that direction is minimized, especially where the photoresist is overdeveloped. Because the features 410 preferably contact the spacers 320 both at butting ends and from the side, a relatively high contact area can be achieved. Preferably, as illustrated, the spacers 320 form a boundary for exactly two faces of the features 410, e.g., line end faces and on one side of the features 320. Moreover, a high contact area can advantageously be maintained even after trimming by overdevelopment. For example, if the features 410 were centered on the spacers 320, trimming may leave the features 410 only contacting the spacers 320 ends. The off-set positioning above, however, allows the features 410 to contact the spacers 320 both at butting ends and from the side, thereby increasing the contact area between those two parts.
It will be appreciated that, in any of the steps described herein, transferring a pattern from a first level to a second level involves forming features in the second level that generally correspond to features on the first level. For example, the path of lines in the second level will generally follow the path of lines on the first level and the location of other features on the second level will correspond to the location of similar features on the first level. The precise shapes and sizes of features can vary from the first level to the second level, however. For example, depending upon etch chemistries and conditions, the sizes of and relative spacings between the features forming the transferred pattern can be enlarged or diminished relative to the pattern on the first level, while still resembling the same initial "pattern." Thus, the transferred pattern is still considered to be the same pattern as the initial pattern. In contrast, forming spacers around mask features can change the pattern.
It will also be appreciated that various modifications of the illustrated embodiments are possible. For example, the pitch of the spacers 320 can be more than doubled. For example, further pitch multiplication can be accomplished by forming additional spacers around the spacers 320, then removing the spacers 320, then forming spacers around the spacers that were formerly around the spacers the 175, and so on. An exemplary method for further pitch multiplication is discussed in U.S. Pat. No. 5,328,810 to Lowrey et al.
In addition, while illustrated equally spaced for ease of illustration, the spacers 320 or the features 410 can each be spaced at varying distances to each other. Moreover, while all are illustrated contacting the spacers 320 from the same side, some of the features 410 can be positioned on different, e.g., sides. Moreover, while illustrated parallel over their entire lengths for illustrate, the distance between the spacers 320 can vary over some or all of their lengths. Preferably, however, the spacers 320, and resulting interconnects 420, are parallel over some distance, e.g., between first and second planes 500 and 502 extending perpendicular to the spacers 320 (FIGS. 18 and 21). For example, the illustrated spacers 320 are preferably parallel in the array region 102 of a DRAM to connect the tightly packed memory cells in that array region. In addition, various parts of the spacers 320 can be formed at angles relative to other parts of the spacers 320. Similarly, parts of the features 410 can be formed at angles relative to the spacers 320 or to other parts of the features 410. For example, the features 410 can diverge away from the points of contact with the spacers 320 to allow for increased separation between those features.
Also, more than two patterns, e.g., corresponding to landing pads and interconnects, can be consolidated on a mask layer before transferring the consolidated pattern to the substrate. In some embodiments, additional mask layers can be deposited above the layer 150. For example, patterns corresponding to landing pads and additional interconnects can be transferred to a supplemental mask layer (not shown) overlying the hard mask layer 150 and then an overlying photodefinable layer (not shown) can be patterned and the pattern transferred to underlying layers. The substrate 110 can then be processed through the resulting mask pattern.
It will be appreciated that while "processing" through the various mask layers preferably involve etching an underlying layer, processing through the mask layers can involve subjecting layers underlying the mask layers to any semiconductor fabrication process. For example, processing can involve ion implantation, diffusion doping, depositing, or wet etching, etc. through the mask layers and onto underlying layers. In addition, the mask layers can be used as a stop or barrier for chemical mechanical polishing (CMP) or CMP can be performed on the mask layers to allow for both planarizing of the mask layers and etching of the underlying layers.
It will also be appreciated that while the preferred embodiments will find application in any context in which features in different mask patterns are overlaid one other, in particularly advantageous embodiments, features formed by pitch multiplication or employing spacers on soft or hard masks are "stitched" or aligned with features formed by a masking technique with a lower resolution. Preferably, pitch multiplied mask features are made to contact features formed by conventional photolithography. Thus, the pitch multiplied features preferably have a pitch below the minimum pitch of the photolithographic technique used for patterning the other features. In addition, while the preferred embodiments can be used to form any integrated circuit, they are particularly advantageously applied to form devices having arrays of electrical devices, including logic or gate arrays and volatile and non-volatile memory devices such as DRAM, ROM or flash memory.
Moreover, the principles and advantages discussed herein are applicable to a variety of contexts in which two or more adjacent mask patterns are to be mated within overlapping regions.
Accordingly, it will be appreciated by those skilled in the art that various other omissions, additions and modifications may be made to the methods and structures described above without departing from the scope of the invention. All such modifications and changes are intended to fall within the scope of the invention, as defined by the appended claims.
patterning interconnects in the other photodefinable layer, wherein the interconnects are wider than the spacers, wherein the interconnects contact the spacers and are aligned with one long side inset from or collinear with a corresponding long side of the spacers.
2. The method of claim 1, wherein the long sides of the interconnects are substantially co-linear with the long sides of the spacers.
3. The method of claim 1, wherein the photodefinable layer comprises photoresist.
4. The method of claim 3, wherein the photodefinable layer comprises positive photoresist.
5. The method of claim 4, wherein the other photodefinable layer comprises photoresist.
6. The method of claim 5, wherein the other photodefinable layer comprises negative photoresist.
7. The method of claim 5, further comprising overdeveloping the photoresist.
8. The method of claim 5, wherein the photoresist is compatible with 248 nm wavelength photolithography systems.
9. The method of claim 1, wherein an other long side of the patterned interconnects opposite from the long side tapers toward an other side of the spacers opposite from the long side of each of the spacers.
10. The method of claim 1, wherein the temporary layer comprises amorphous carbon.
11. The method of claim 10, further comprising transferring the patterned interconnects and the pattern of spacers to an additional mask layer underlying the pattern of spacers.
12. The method of claim 11, wherein the additional mask layer comprises amorphous carbon.
13. The method of claim 1, wherein forming a pattern in the photodefinable layer comprises exposing, developing and etching the photodefinable layer and subsequently isotropically etching the photodefinable layer.
14. The method of claim 1, wherein a hard mask layer separates the temporary layer and the photodefinable layer.
15. The method of claim 14, wherein the hard mask layer comprises a dielectric antireflective coating.
16. The method of claim 15, wherein the dielectric antireflective coating comprises silicon oxynitride.
17. The method of claim 1, wherein depositing a blanket layer of spacer material comprises depositing a layer of silicon by chemical vapor deposition.
wherein the spacer forms a boundary for only two faces of the photoresist line in the contact region.
19. The method of claim 18, wherein one of the two faces contacts the end of the spacer.
20. The method of claim 19, wherein another of the two faces contacts a long side of the spacer.
21. The method of claim 18, wherein the photoresist line has a height less than a height of the spacer.
22. The method of claim 18, wherein the photoresist line is formed by photolithography.
23. The method of claim 22, further comprising overdeveloping the photoresist line.
24. The method of claim 18, wherein the photoresist line comprises negative photoresist.
25. The method of claim 18, wherein the substrate comprises a conductor.
26. The method of claim 18, wherein the photoresist line and the spacer define a conductive interconnect.
patterning a plurality of features in the photodefinable layer.
28. The process of claim 27, wherein forming the first plurality of mask lines comprises pitch multiplication.
29. The process of claim 27, wherein patterning the plurality of features comprises irradiating and developing the photodefinable layer.
30. The process of claim 29, wherein patterning the plurality of features comprises overdeveloping the photodefinable layer.
31. The process of claim 27, wherein the mask lines define a plurality of first conductive interconnects, each of the first conductive interconnects having a first critical dimension.
32. The process of claim 31, wherein the features define a plurality of second conductive interconnects, each of the second conductive interconnects having a second critical dimension.
33. The process of claim 32, wherein the second critical dimension is larger than the first critical dimension.
34. The process of claim 32, wherein an end of each of the first conductive interconnects abuts an end of each of the second conductive interconnects.
35. The process of claim 34, wherein the ends of the second conductive interconnects contact an entire width of the ends of the first conductive interconnects.
36. The process of claim 34, wherein the ends of the second conductive interconnects contact less than an entire width of the ends of the first conductive interconnects.
37. The process of claim 36, wherein the ends of the second conductive interconnects partially overlap the ends of the first conductive interconnect.
38. The process of claim 27, wherein forming the photodefinable layer comprises scan coating photoresist.
39. The process of claim 27, wherein forming the photodefinable layer comprises depositing photoresist and etching back the deposited photoresist.
40. The process of claim 39, wherein depositing photoresist comprises performing a spin-on process.
41. The process of claim 39, wherein the thickness of the photodefinable layer is about 80% or less than a height of the mask lines.
42. The process of claim 41, wherein the thickness of the photodefinable layer is about 75-50% of the height of the mask lines.
43. The process of claim 41, wherein the integrated circuit is a DRAM.
a photodefinable layer contacting the mask lines, the photodefinable layer having a thickness less than a height of the mask lines.
45. The partially fabricated integrated circuit of claim 44, wherein the photodefinable layer comprises a pattern of features, wherein one line of photodefinable material contacts an end of each of the mask lines.
46. The partially fabricated integrated circuit of claim 44, wherein the mask lines extend in spaced, generally parallel relation to one another between first and second spaced planes extending perpendicular to the lines.
47. The partially fabricated integrated circuit of claim 44, wherein the thickness of the photodefinable layer is about 80% or less than a height of the mask lines.
48. The partially fabricated integrated circuit of claim 47, wherein the thickness of the photodefinable layer is about 75-50% of the height of the mask lines.
49. The partially fabricated integrated circuit of claim 44, wherein the substrate comprises a conductor.
50. The partially fabricated integrated circuit of claim 44, wherein an amorphous carbon layer is provided between the substrate and the mask lines.
51. The partially fabricated integrated circuit of claim 44, wherein the photodefinable layer comprises a pattern of contacts to the mask lines, wherein material of the photodefinable layer defining the contacts abuts ends of the mask lines.
52. The partially fabricated integrated circuit of claim 51, wherein a side of the material is flush with a side of the mask lines, wherein an opposite side of the material protrudes beyond an opposite side of the mask lines.
53. The partially fabricated integrated circuit of claim 52, wherein, from a top view, the opposite side of the material curves towards the opposite side of the mask lines.
wherein an end of each of the second interconnect portions contacts an end of each of the first interconnect portions, wherein one side of each of the second interconnect portions, extending along a length of one of the second interconnect portions, is substantially collinear with or inset from one side of each of the first interconnect portions, extending along a length of one of the first interconnect portions.
56. The integrated circuit of claim 54, wherein a corner of each of the second interconnects, opposite the one side of the second interconnects, protrudes beyond an other side of each of the first interconnects opposite the one side of the first interconnects.
57. The integrated circuit of claim 54, wherein a pitch of the first plurality of interconnects is less than 100 nm.
58. The integrated circuit of claim 57, wherein the first plurality of interconnects are pitch multiplied interconnects.
59. The integrated circuit of claim 57, wherein the interconnects comprise copper.
60. The integrated circuit of claim 57, wherein the interconnects comprise aluminum.
a plurality of interconnects, the interconnects each having a first portion and a second portion, wherein the first portion of the interconnects are substantially parallel to each other between first and second spaced planes extending perpendicular to the lines and wherein the first portion and the second portion contact in an overlap region, wherein only one corner of the second portion protrudes beyond a side of the first portion in the overlap region.
62. The integrated circuit of claim 61, wherein the second portion is wider than the first portion.
63. The integrated circuit of claim 61, wherein the first and second spaced planes are in an array region of a memory chip.
64. The integrated circuit of claim 63, wherein the second portions are located in a periphery of the memory chip.
65. The integrated circuit of claim 61, wherein the interconnects comprise a metal.
66. The integrated circuit of claim 61, wherein a pitch of the first portions is about 100 nm or less.
67. The integrated circuit of claim 61, wherein a corner of the first portion protrudes beyond a side of the second portion in the overlap region.
68. The integrated circuit of claim 61, wherein a side of the second portion opposite the protruding corner is flush with a corresponding side of the first portion.
DE3682395D1 (en) 1986-03-27 1991-12-12 Ibm A process for the production of side structures.


text:
if Chef::Config[:solo]
  Chef::Log.warn 'ssh_known_hosts requires Chef search - Chef Solo does not support search!'

  # On Chef Solo, we still want the current node to be in the ssh_known_hosts
  hosts = [node]
else
  hosts = search(:node, 'keys_ssh:*').collect do |host|
    {
      'fqdn' => host['fqdn'] || host['ipaddress'] || host['hostname'],
      'key'  => host['keys']['ssh']['host_rsa_public'] || host['keys']['ssh']['host_dsa_public']
    }
  end
end

# Add the data from the data_bag to the list of nodes.
# We need to rescue in case the data_bag doesn't exist.
begin
  hosts += data_bag('ssh_known_hosts').collect do |entry|
    item = data_bag_item('ssh_known_hosts', entry)
    {
      'fqdn' => item['fqdn'] || item['ipaddress'] || item['hostname'],
      'key'  => item['rsa'] || item['dsa']
    }
  end
rescue
  Chef::Log.info "Could not load data bag 'ssh_known_hosts'"
end

# Loop over the hosts and add 'em
hosts.each do |host|
  unless host['key'].nil?
    # The key was specified, so use it
    ssh_known_hosts_entry host['fqdn'] do
      key host['key']
    end
  else
    # No key specified, so have known_host perform a DNS lookup
    ssh_known_hosts_entry host['fqdn']
  end
end

redpajama_set_name: RedPajamaGithub


Press to view Puttin' On The Ritz - Trumpet 3 Sheet Music and can be viewed directly in your browser - no download is required. These can be printed just once but at any time... Print and download easy piano sheet music for Puttin' On The Ritz by Fred Astaire. Sheet music arranged for sheet music Puttin' On The Ritz digital sheet music.
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Original: Puttin' on the Ritz composed by Irving Berlin. Puttin' on the Ritz. SSA Choir Piano. Translation: Have you seen the well-to-do up and down Park Avenue.
Download or print Irving Berlin Puttin' On The Ritz sheet music notes, chords in minutes. Check if it is transposable. SKU of the score is 176082. Check if it is transposable. SKU of the score is 176082.


text:
Hitachi Group
About Social Innovation
Think Ahead
Nearly permanent digital archive technology for preserving valuable information for 300 million years
Nearly permanent digital archive technology
for preserving valuable information for 300 million years
Research on leaving valuable data to future generations is underway throughout the world. Current data storage media forms have a relatively short life expectancy and would not survive through fire or other disasters, making it ineligible for nearly permanent archiving applications. Hitachi took notice and is carrying out research & development into archive technologies that will enable the nearly permanent storage of data, focusing efforts on fused silica.
Video: Hitachi's fused silica recording technology
Demand is increasing for the long-term and reliable preservation of valuable data, such as cultural heritage of historical significance and public documents, as well as personal records for future generations. However, the media forms currently used for this task, optical disks and hard drives, do not have the required lifespan or durability. Taking this on as a challenge, Hitachi is pursuing research & development into cutting-edge technology for the nearly permanent preservation of digital archives.
In 2008, Hitachi launched a research project to develop nearly permanent data storage. In the following year, research results suggested that data recorded in fused silica could last for 300 million years. In 2011, Hitachi launched a joint research project with Kyoto University. This project solved a variety of problems, including spherical aberration caused by a lens, leading to the demonstration in 2014 of a media form with both the recording density of a Blu-ray disk and nearly permanent storage capacity.
Fused silica glass archive technology is superior in that it retains the ability to preserve data for over 300 million years and can withstand temperatures as high as 1,000°C. Using this technology, in December 2014, a message for 300 million years into the future was recorded onto fused silica, which was then mounted on an ultracompact artificial satellite. Hitachi will continue to devote efforts to research & development into the nearly permanent storage of the cultural assets and cultural heritage of human civilization.
Hitachi sets its sights on fused silica: Heat and water resistant
With the progress of information technology in our increasingly networked society, the recording media in use has moved quickly from paper to floppy disks, optical disks, hard drives, and a variety of other digital media. Demand is increasing for a long-term and reliable means of preserving valuable data, such as cultural heritage of historical significance and public documents, as well as personal records for future generations. Although optical disks and hard drives have sufficient recording density, for purposes of nearly permanent preservation, they are lacking in the durability needed to resist external stress and for long-term preservation capacity.
The goal of nearly permanent life is a given. The primary goals, however, are (1) the ability to withstand fluctuations in temperature and humidity as well as floods, fire, and other external stresses, and (2) for the archives not to need a specific device for the reading of their contents.
Hitachi finds that fused silica is a very promising material for recording media because it is chemically stable and highly resistant to heat and water, as well as being resistant to radiation.
Hitachi achieves 300-million-year data-storage lifespan and recording density comparable to Blu-ray discs™
In 2008, Hitachi launched a research project to develop nearly permanent data storage as part of its "Innovation Research," and in 2009, research results suggested that data recorded in fused silica could last for 300 million years.
In 2011, Hitachi launched a joint research project with Prof. Kiyotaka Miura and Yasuhiko Shimotsuma, Ph.D. from the Kyoto University School of Engineering to improve recording density and simplify the reading process for data storage in fused silica. The result of this project was the use of a femtosecond pulse laser* for recording data and an optical microscope for reading data. The femtosecond pulse laser employs a laser pulse of less than one ten-trillionth of a second to form dots with a different refractive index inside the fused silica. Dots recorded like this represent ones, and the areas without dots represent zeroes, in this way recording digital data in multiple layers. To read the data, an optical microscope scans layer by layer to read the configuration of recorded dots.
Graphic 1: A femtosecond pulse laser and spatial light modulator are used for high-density, multi-bit recording
The laser creates dots to record data
An optical microscope is used to read the data, and a computer processes the image
In 2012, the joint research project achieved a recording density comparable to a CD by recording four layers of data in fused silica. In 2013, the joint research project developed the technology to reach a recording density comparable to a DVD by recording 26 layers of data.
Dramatic innovations were needed in recording and reading data to achieve this level of density. The joint research project developed multi-layer recording technology and simultaneous multi-bit recording technology, using a spatial light modulator to enable high-speed and high-density recording. This makes it possible to simultaneously record around 300 bits of information. To improve recording density, the joint research project developed and used outline enhancing signal processing technology to reduce noise and artifacts from other layers.
Further, the joint research project proved that data recorded in fused silica was able to withstand accelerated temperature tests at 1,000°C for two hours and could have a nearly permanent life.
However, as the joint research project worked on increasing the number of layers to record to improve recording density, some unexpected issues arose. Recording more layers requires writing data deeper inside the fused silica, in layers that are only 60 micrometers apart. As data was recorded deeper inside the fused silica, the dots became distorted depth-wise, creating interference that caused errors in reading data from other layers. Another issue was that the dots recorded in deeper layers became less sharp when being read. These issues were due to spherical aberration caused by the difference between the refractive index of the air and that of the fused silica. The joint research project resolved these problems by using a spherical aberration correction lens, preventing the phenomena of elongation and blurring of the dots. To reduce reading errors and to meet reliability standards needed for practical application, the joint research project also developed and applied a new noise reduction algorithm. (See graphic 2)
The joint research project resolved the problems with multi-layer recording and succeeded in producing a prototype for 100-layer data storage in fused silica in 2014. This means that the joint research project proved that a nearly permanent life of 300 million years could be achieved for data storage at 1.5 GB/inch², which is comparable to Blu-ray discs™.
Possibilities still remain for further increasing of the number of layers.
femtosecond pulse laser : The duration of a laser beam firing is called its pulse width. A femtosecond pulse laser is a laser that has reduced the duration of its pulse to about one ten-trillionth of a second, 10-13 seconds, or less.
Graphic 2: The data reading process met standards for practical application through using a spherical aberration correction lens and other innovative methods
Hitachi continues R&D to preserve the heritage of human civilization
Images in fused silica glass and a message for 300 million years in the future were sent into space aboard the Shin-en 2 probe
Currently, there are research initiatives underway around the world to develop long-life data storage using various methods, including semiconductor memory and the DNA of bacteria. However, none of these efforts have even come close to the technology developed by Hitachi in being able to store data for 300 million years or withstand temperatures of 1,000°C. Fused silica storage also has the added advantage that users can draw images, such as letters, artwork and photographs, by using dots in addition to storing digital data. In December 2014, a fused silica glass lithograph featuring images and a message for 300 million years in the future was created using this technology. These were launched into space on the Hayabusa 2 rocket as part of the payload for Shin-en 2, a small-sized space probe that was jointly developed by the Kyushu Institute of Technology and Kagoshima University.
Hitachi considers that cultural heritage such as written language, paintings, photographs, and sound recordings are valuable assets that should be preserved for future generations. Hitachi continues to work on research and development to preserve such valuable data for close to eternity using materials that are highly resistant to heat and water, as well as being resistant to radiation.
Solutions By: Research & Development Group, Hitachi, Ltd.
Hitachi Develops Basic Artificial Intelligence Technologies to Strengthen Management Decision-Making at Global Enterprises
Hitachi's Business Improvement Service Harnesses AI to Solve Corporate Management Issues
Sweet Spot: How Hitachi Tech is Helping Save the Bees
Hitachi develops artificial intelligence capable of grasping site conditions and issuing work orders
Hitachi develops technology capable of estimating demographic attributes by measuring human behavior through analysis of 3D imaging data
Hitachi develops technology for secure anonymization of personal data
Diverse application technologies to produce EMIEW, a robot supportive to people
In March 2017, the Japanese government formulated the Work Style Reform Action Plan.
Disclaimer and copyrights
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redpajama_set_name: RedPajamaCommonCrawl


text:
Colombia :: Medellin's Comuna 13
"Once one of the most dangerous places in the world, Comuna 13 is now a cradle of art and culture."
The city of Medellin is divided into communes. Comuna 13 consists of thousands of brightly colored houses at the top of a very steep hill and is different from the other 15 comunas because of the enormous amount of colorful street art and graffiti.
"Tucked away in a corner of the former 'murder capital of the world' is Comuna 13, once one of the most dangerous places in the world, and now a cradle of art and culture, and a symbol of the fight against terror."
– The Hindu
You'll find a different mural on every wall of every building and smaller art pieces in between. Added to this is the many street musicians and kids trying to jump start their rap career, the vendors selling original art, prints and trinkets as souvenirs. You can also test out the Mango Popsicle dipped in honey water… At least I think that's what it was, the water was so sweet even I couldn't finish it – and that's saying a lot.
I got on another guided tour this time, but it wasn't for safety and you really don't have to worry about going just you and a friend. We saw several people in groups of two or three with no guides, handling their Lonely Planet books and trying to figure out the history of this place and Franklin told us it was perfectly fine. I trust Franklin, he could rap. For myself though, I wanted the more "curated experience" again. I have come to realize that I, (at least when I am fatigued), prefer someone to take me to a place and point out and explain to me the most important parts. Preferably with some storytelling and tidbits in there. And we certainly got that with our guide/storyteller/rapper/chef, Franklin.
Franklin, our guide
I got myself to the metro station "San Javier Cll.45 #98-80 Medellin" and after a while the tourists started congregating. We were all there for the tour and each of us were assigned a guide. The guides broke the group up in smaller groups and got a taxivan each for their specific group. It was kind of like being back in elementary school and being divided up for theme day or something. In my van there were people from the Netherlands, England, France, and another European country I can't remember now. I ended up bonding with Emero and Jamie from my other motherland while we "sped" along the crowded street towards the starting point of our walking tour.
Emero, Jamie and I
Look here, Dutch people!
The French Couple (their kids cheered them on to kiss for the camera *lol*)
"At first glance, the graffiti is hard to understand: a herd of elephants weeping, a group of disoriented people looking nowhere in particular. But hidden within every piece of art in Comuna 13 is a strong message, not just to the residents of the commune, but to the world. If you look closer, every elephant in the herd carries a white handkerchief to denote peace, while thick tears roll down their eyes, despondent about the violence once rampant here. It is hard for people to forget the violence that was once a part of their lives; and elephants have the greatest memory."
After the death of Escobar there were several gangs that tried to take control of Medellin. This lead to the bloody wars that are infamous now. Pop culture has no shortage of series, books and music dedicated to Escobar's reign and the consequences of it. Comuna 13 was on the highway used to transport drugs out of Medellin and as gang members wreaked havoc on the surroundings the violence erupted and millions of people lost their lives before the government stepped in.
The government didn't do a good job though. I fact, they didn't distinguish between drug lord, trafficker and civilian, so for four days weapons were fired en masse at civilian homes to target gangsters. The loss of innocent, civilian lives was horrific. In addition, ambulances could not negotiate the steep slope up to the comuna so first responders couldn't even help. This was when the people of Comuna 13 came together and waved white handkerchiefs symbolising peace, and ending the bloodshed. (Very simplified, but this is the story. The civilians were desperate and persuaded the soldiers on both sides to stop by waving the handkerchiefs and risking their lives getting wounded help).
In the aftermath artists protested by splashing the walls with colour to depict the people's suffering. And from this came the famous street art of Comuna 13.
Art in Comuna 13
"Follow me on Insta!"
Neon art gallery!
What started as a protest has grown into the areas greatest means of income today. Comuna 13 welcomes tourists from all over the world and entertain them while they drink the beer, listen to the music and are captivated by the stories and art of the place. I certainly was. I didn't buy any original art (this time), I ended up with a fridge magnet and some postcards trying to be all smart about my expenses… I'm an idiot. But at least I have a fridge magnet. We also got to see a small gallery where they paint 3D paintings in neon colours. We got glasses on and everything – it was spectacular! (The pictures above do not translate the actual experience).
This is the art piece on my fridge magnet. I have the taste. There are different animals hidden within the lion (easier to spot on mine as it doesn't have the writing over it).
Franklin met up with some of his pals (I mean, he knew everyone there so…) and they gave us a show rapping about stuff I couldn't understand (it was in Spanish), but it sounded really good. Franklin even stepped in for a verse here and a chorus there.
Comuna 13 view
Franklin and his flock
Comuna 13
Franklin sings
Artisanal Beer ❤
Franklin and I
"National Rap Show"
SLIDES!!!111
CLINTON!!111
Local Café in Comuna 13
Comuna 13 Art
After a long day with some of the hottest sun we'd had so far and too many impressions and stories to count (to be honest I think I remember about half the stuff I was told), we could choose to either call it quits and go home or get a trip on the Metrocable (the cable car/gondola in Medellin). It was even included in our tour ticket, so Emero, Jamie and I decided to go.
It started operations in 2004, has five separate lines and carries approximately 30,000 people daily. It's a great compliment to the metro and bus system and given that Medellin is surrounded by mountains it makes it way easier for the people to reach some of the city's informal settlements on the steep hills. We ended up on Line J and took it to the top, the station was called "Aurora Cll.64 #104-69". Just rolls off the tongue that one…
"Soon after officials saw the enormous success of Line K, plans to proceed with another line – Line J – was immediately on the table. It officially opened in 2008. Similar to Line K, it also has four stations: San Javier, Juan XXIII, Vallejuelos and La Aurora. The entire length of Line J runs along 2.7 km of cable."
At the top we found a funky building decorated with panels covered in various colours and decorations. I later found out it houses swimming pools and apparently you can "do sports there", so maybe it's a gym(?) – took photos anyway, the building was cool. We also saw a lovely terrace for taking in the view of the whole valley below, it was so beautiful. This is where I saw something that looked like a tiny kite far, far in the distance… So far away I couldn't make out what it was, but Jamie said "that's a kite". When I asked "how do they get it all the way up there then?" (cause it was SERIOUSLY high up!), Jamie went into that total "Brit Dry Mode " and just said: "String."
Thanks, Jamie. ❤
View from the cable car
At the top: Piscina Nuevo Occidente (this is a swimming pool place)
Posted in: 2020, America, RTW, South America, Travelling | Tagged: 2020, America, Art Gallery, Aurora Cll.64 #104-69 Medellin, Bakoyma, BakoymaTravels, British, Brits, Cable Car, Colombia, Commune, Comuna 13, Dutch People, Emero, Escobar, Franklin, Fridge Magnet, Gondola Lift, Guide, Jamie, Kite, Line J, Medellin, Metrocable, Music, Neon, Pablo Escobar, Piscina Nuevo Occidente, Rap, Round The World, RTW, San Javier, South America, Street Art, The Hindu, Tour, Tour Guide, Travel
COLOMBIA :: GUATAPÉ & Pablo Escobar's Bombed Out Hacienda
Colombia :: Bogotá, food poisoning & the end of my adventure


text:
Grazia Deledda (Szardínia, Nuoro, 1871. szeptember 27. – Olaszország, Róma, 1936. augusztus 15.) Nobel-díjas olasz (szárd) írónő.

Élete
1871-ben született a szardíniai kisvárosban, Nuoróban, egy hétgyerekes földbirtokos család ötödik gyermekeként. Apja jómódú vállalkozó volt, és egy időben Nuoro polgármestere. Anyja mélyen vallásos volt, és gyermekeit is szigorú vallásos nevelésben részesítette.

Az elemi iskolát Nuoróban járta, azután magánúton folytatta tanulmányait egy olasz elemi iskolai tanárral, aki olasz-, latin- és franciaórákat adott neki. (Akkoriban nem volt szokás a lányokat az elemi iskolán túl taníttatni.) A későbbiekben autodidakta módon ismerkedett az irodalommal.

Íróként a L'ultima moda című folyóirat oldalain debütált néhány elbeszéléssel.

1899-ben Rómába költözött, és ezután több művét is kiadták: Anime oneste (1895), Il vecchio della montagna (1900).

1903-ban az Elias Portolu kiadó szerződtette, és több regényét és színházi darabját is megjelentette. Cenere (1904), L'edera (1908), Sino al confine (1911), Colombi e sparvieri (1912), Canne al vento (1913), L'incendio nell'oliveto (1918), Il Dio dei venti (1922). A Cenere című művéből filmet is forgattak.

Művészetét külföldön is elismerték, Gorkij és D. H. Lawrence is elismerően nyilatkozott róla.

Munkássága

Első igazi irodalmi sikerét az Elias Portolú (1903) című írásával érte el, melyet minden európai nyelvre lefordítottak.

Munkáin megfigyelhető a verizmus képviselőjének, Giovanni Vergának és a dekandencia képviselőjének, Gabriele D'Annunziónak a hatása.

Fontosabb művei

 Fior di Sardegna (1892)
 La via del male (1896)
 Racconti sardi (1895)
 Anime oneste (1895)
 Elias Portolu (1903)
 Cenere (1904)
 L'edera (1908)
 Canne al vento (1913)
 Marianna Sirca (1915)
 La madre (1920)
 La fuga in Egitto (1925)
 Il sigillo d'amore (1926)
 Cosima (1937) posztumusz kiadás
 Il cedro del Libano (1939) posztumusz kiadás

Magyarul megjelent művei
 A repkény. Regény; ford. Sebestyén Károlyné; Phőnix, Bp., 1908 (Az Otthon könyvtára) Online hozzáférés
 Varázs alatt. Elbeszélés; ford. Balla Ignác; Lampel, Bp., 1912 (Magyar könyvtár)
 A mi Urunk. Regény; ford. Balla Ignác; Franklin, Bp., 1914
 Deledda Gráciaː Mint a szélben a nád. Regény; ford. Kőrösi Sándor; Athenaeum, Bp., 1921 (Athenaeum könyvtár)
 Jó lelkek; ford. Boros Ferenc; Franklin, Bp., 1931 (Külföldi regényírók)
 Szerelemből gyilkolt. A repkény; ford. Székely Éva; Móra, Bp., 1991

Források
Emilio Cecchi, Grazia Deledda, in Prosatori e narratori, in Storia della letteratura italiana. Il Novecento, Milano, Garzanti, 1967
Antonio Piromalli, Grazia Deledda, Firenze, La Nuova Italia, 1968
Natalino Sapegno, Prefazione a Romanzi e novelle, Milano, Mondadori, 1972
Giulio Angioni, Grazia Deledda, l'antropologia positivistica e la diversità della Sardegna: Grazia Deledda nella cultura contemporanea, Nuoro, 1992, 299-306; Introduzione: Tradizioni popolari di Nuoro, Bibliotheca sarda, Nuoro, Ilisso, 2010

Jegyzetek

Források
 Az OSZK online katalógusa
 Grazia Deledda önéletrajza a nobelprize.org-on

Olasz költők, írók
Irodalmi Nobel-díjasok
Nobel-díjas nők
1871-ben született személyek
1936-ban elhunyt személyek
Olasz nők
Olasz Nobel-díjasok
Szardíniai nők

redpajama_set_name: RedPajamaWikipedia


Organic gardening is becoming more popular as it gets more and more expensive to buy fresh and organic foods at the grocery store. Some stores do not sell organically grown fruits and vegetables, so it requires going to a specialty grocery store if those foods are desired, which is a hassle in addition to being more expensive. The best organic gardening tip of all is to start growing an organic garden in the backyard where fresh fruits and vegetables can be had whenever they are desired.
There are certain organic gardening supplies that are needed in order to start an organic garden, however, most things can be obtained around the house and yard, since organic gardening by definition is a natural way to garden. The first organic gardening tip is to check the soil in the place where the garden is going to be formed. Soil is extremely important to organic gardening since it supplies the nutrients that the plants need to grow and mature. It is best to break up the soil so that air can get into it, which is called aerating the soil.
Besides aerating the soil, organic gardening tips from organic magazines say to prepare the soil and make sure it has just the right amount of sun or shade according to the plants that will be planted in it. If the area has too much sun, then there will be too much time spent in watering the garden and even so, still might not be enough for young plants with shallow roots. If there is too much shade, then the young sprigs do not have enough energy to grow and the garden will fail as well.
The soil must be prepared before the seeds or young plants are planted so that it is as full of nutrients as possible. Compost is great mulch, full of all the good things that new plants enjoy, and it can be made in the yard next to the garden. Compost can also be bought in stores, but it is free when made in the yard. All it takes to start a compost pile is to find an out of the way place, pile some leaves, grass clippings, or rotten veggies and fruits on top of it and let it sit for a couple of weeks. The longer it goes, occasionally adding new materials to the top of it, the richer the soil underneath is getting to be. That soil is full of nutrients that can be spread around the plants to add some food to the soil, and it is an excellent preparation tool for a new garden according to organic gardening tips.


Thank you for considering a print purchase. If you choose to order a print, I'll make a modest profit that will enable me to keep exploring our planet's wildlife. I use Bay Photo to fulfill print orders. You can visit their site to see the products they offer.
One of my favorite options is their prints mounted on masonite. Available in standard sizes, these high quality photographic prints are mounted to 1/8″ hardboard. This keeps the print rigid and perfectly flat which simplifies framing, or you can add a wall hanger and hang the print without a frame.
Take Bay Photo's price and ad 10¢ per square inch. So for example an 8″x10″ photographic print mounted to masonite is $9.49 on Bay Photo . . . 8 x 10=80 square inches . . . 80 x 0.10=$8. Add $9.49 + $8 for a grand total of $17.49 + plus shipping which is very reasonable.
If this is too much math, please send me an email with a link to the image you are interested in and what type and size of print you would like and I'll send you a bid. You'll work directly with me and I will work with Bay Photo to assure your print is perfect.
Prints take about a week for delivery within the U.S.


Hello! My name is Caroline Guske, and I'm a singer-songwriter raised in central Virginia. My style is constantly being affected by different music I hear. I can't exactly categorize my own music into one genre because I always want my music to be evolving, and I'm open to many different styles: pop, R&B, jazz, blues, folk, alternative rock, etc.


text:
What's Going on in Libya?
" "What is going on in Libya?" Middle East analyst Raymond Ibrahim asks in reference to the rising persecution of Christians in the country. Four Christian foreigners were arrested in Benghazi on February 10. Three days later, two more Christians from Egypt were arrested, one of whom, identified as Sherif Ramses, was reportedly tortured. Three days after that, a seventh Christian, also from Egypt, was arrested. Then, on February 27, at least 48 Christians were arrested (with some reports placing the number at closer to 100), and some were reportedly tortured. Days later, a Coptic Church was attacked in Benghazi and two priests were assaulted. "It is becoming clear that these arrests are increasingly less about actual Christian evangelism to Muslims, and more about Muslim hostility to Christians," Ibrahim writes."
Read Mass Arrest and Torture of Christians in Libya, by Raymond Ibrahim at www.algemeiner.com


Which girl from the Twilight Series would anda wanna be?
What book of the Twilight Saga anda like most?
Do anda think that Jasper's ability is cool?
If anda got changed into a vampire, who would anda want to do it?
if u Cinta twilight click here !!!
if anda were a boy who would anda rather alice atau rosalie?
Hi, this is the 17th chapter of My True Love. Some of anda may have not read it, if anda havent then please read on, but anda might want to go and check out the others first (they are all on my page) the next-and last!- chapter will be telah diposkan in a few days so, keep and eye out and I hope anda enjoy!
We had all come here for a picnic today, in the meadow, because it was a sunny day. We were all here the whole pack and all of the Cullen's. The meadow was deserted and it looked peaceful and serene with pelangi, rainbow spots dancing around.
Sorry for the delay of chapter 24- my computer broke *arrrg!* so I had to re-write the whole chapter- but I hope anda enjoy.
Okay so this chapter is my favourite and I think anda are going to enjoy (crossed fingers) it! Okay so just remeber to leave your feedback-it's always great to see it.
Alice wouldn't let me go until she and Rosalie had telah diberi me a complete makeover; I didn't complain though, it was nice to have girl time. Jacob gave me a dazzling smile as I walked back into the living room a full jam later, he and Emmet and jasper had probably been chatting about some new turbo engine.
Okay shapter 10 is finally ready and chapter 11 is well on its way (I think anda will like chapter 11!) so keep looking for it!
It was like someone was trying to wake me from a deep sleep. I wanted to wake up but I couldn't alih there was too much pain. That's when I heard the voice, his beautiful voice.
"No Nessie, don't stop breathing. Keep your hati, tengah-tengah beating, breath Nessie breathe!" Jacob sobbed over my chest.
"Jacob, anda need to let me look at her, it's the only way to save her," Carlisle said, worry in his calm voice. Jacob didn't say anything but leaned back and took my hand.