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The results in Table 6 found the resist composition of the present invention demonstrates favorable lithography per› formance such as EL, MEF, and CDU in hole patterning by organic solvent development. 

## [Examples 3-1 to 3-12, Comparative Examples 3-1 to 3-8] NTD; ArF Exposure Patterning Evaluation (2); Line and Space Evaluation 

The resist compositions of the present invention (R-1 to 12) prepared by the compositions according to the above Tables 4 and 5 and resist compositions (R-13 to 20) for Comparative Examples were spin-coated on a substrate for try layer process obtained by coating a spin-on carbon film ODL-101 (Product from Shin-Etsu Chemical Co., Ltd.) 200 nm in thickness, and a silicon-containing spin-on hard mask SHB-A940 (silicon content: 43% by mass) 35 nm in thick› ness thereon, and baked at 100° C. for 60 seconds using a hot plate to form a resist film 100 nm in thickness. 

The product was subjected to pattern exposure using ArF immersion excimer laser scanner (Product from Nikon Cor› poration, NSR-610C, NAl.30, a0.98/0.78, 4/5 annular illu› mination), and a 6% halftone phase shift mask with a pitch of 100 nm a line width of 50 nm (on-wafer size) for post-exposure 60-second heat treatment (post-exposure bak› ing: PEB). Thereafter, butyl acetate was discharged from a development nozzle by rotation for 3 seconds at 30 rpm and subjected to stationary puddle development for 27 seconds. Consequently, line and space pattern (LS pattern) where a non-exposed area protected from light by a mask is dis› solved into a developer to cause image inversion was obtained with a space width of 50 nm and a pitch of 100 nm. 

## [Sensitivity Evaluation] 

The obtained LS pattern was observed with electron microscope, and the optimum exposure dose (Eop, mJ/cm 2 ) for obtaining a LS pattern with a space width of 50 nm and a pitch of 100 nm was determined. 

## [Exposure Latitude (EL) Evaluation] 

In exposure latitude evaluation, the exposure latitude (unit: %) was determined from exposure dose which pro› vided a LS pattern with a hole diameter of 50 nm–l 0% ( 45 nm to 55 nm), according to the following formula. 

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El: Optimum exposure dose providing LS pattern with a space width of 45 nm and a pitch of 100 nm 

E2: Optimum exposure dose providing LS pattern with a space width of 55 nm and a pitch of 100 nm 

Eop: Optimum exposure dose providing LS pattern with a space width of 50 nm and a pitch of 100 nm 

## [Mask Error Factor (MEF) Evaluation] 

The mask pitch was fixed, and the mask line width was changed, and the films were irradiated with the optimum exposure dose in the above sensitivity evaluation to form patterns. From the changes in mask line width and pattern 

space width, MEF values were determined according to the following formula. The performance is favorable as the value approaches 1. 

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b: constant 

## [Line Width Roughness (LWR) Evaluation] 

The LS pattern obtained by irradiating films with the optimum exposure dose was subjected to dimensional mea› lO surement at 10 portions in the longitudinal direction of the space width using TDSEM (S-9380, Product from Hitachi High-Technologies Corporation). The resulting standard deviation (a) was multiplied by three (3a) to be defined as a LWR. As the 3a value is small, a pattern with small 15 roughness and uniform space width can be obtained. 

## [Defect Density Evaluation] 

The number of defects in a pattern formed after develop› ment was examined by a defect inspection system KLA2800 (Product from KLA-Tencor) to determine the defect density according to the following formula. 

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Formed pattern: 50 nm 1:1 line and space’s repeated pattern Defect inspection conditions: light source UV, inspected pixel size 0.28 µm, cell to cell mode 2 

In this evaluation, "favorable" is under 0.05/cm , and "unfavorable" is 0.05/cm 2 or more. 

Table 7 shows the results of the evaluations. 

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The results in Table 7 found the resist composition of the present invention demonstrates favorable lithography per› formance such as EL, MEF, and LWR in negative patterning by organic solvent development, as well as effective defect reduction. It was thus found that the resist composition of the present invention is effective in development process of an organic solvent. 

