content_image/896919.jpg content_image/896920.jpg
A$_{2 }$ represents a group that when acted on by an acid, is cleaved. 

[16] The composition according to any ofitems [1] to [15], wherein the resin (Ab) has a weight average molecular weight ranging from 1000 to 200,000. 

[17] The composition according to item [16], wherein the resin (Ab) has a weight average molecular weight ranging from 1000 to 100,000. 

[18] The composition according to item [17], wherein the resin (Ab) has a weight average molecular weight ranging from 1000 to 50,000. 

[19] The composition according to item [18], wherein the resin (Ab) has a weight average molecular weight ranging from 1000 to 25,000. 

[20] The composition according to any of items [1] to [19], further comprising a basic compound. 

[21] The composition according to item [20], wherein the basic compound is a compound containing a functional group with proton acceptor properties, which compound when exposed to actinic rays or radiation, is decomposed to thereby produce a compound exhibiting proton acceptor properties lower than, or no proton acceptor properties due to dissipation of, the proton acceptor properties of the compound, or exhib› iting acid properties derived from the proton acceptor prop› erties of the compound. 

[22] The composition according to any ofitems [1] to [21], further comprising a surfactant. 

[23] The composition according to any ofitems [1] to [22], further comprising a solvent. 

[24] The composition according to item [23], wherein the solvent comprises propylene glycol monomethyl ether acetate. 

[25] The composition according to item [24], wherein the solvent comprises propylene glycol monomethyl ether. 

[26] The composition according to any of items [1] to [25] 35 to be exposed to EUV light. 

[27] The composition according to any of items [1] to [25] to be exposed to a KrF excimer laser, electron beams or X-rays. 

[28] An actinic-ray- or radiation-sensitive film formed from the composition according to any of items [1] to [27]. 

[29] A method of forming a pattern, comprising forming the composition according to any of items [ 1] to [27] into a film, exposing the film to light, and developing the exposed film. 

[30] The method according to item [29], wherein the expo› sure is performed using EUV. 

[31] A semiconductor device manufactured by a process comprising the method of item [29] or [30]. 

The present invention has made it feasible to provide an actinic-ray- or radiation-sensitive resin composition that can simultaneously satisfy high sensitivity, favorable roughness performance, favorable pattern shape, favorable dry etching resistance and reduction of development defects, and to pro› vide an actinic-ray- or radiation-sensitive film from the com- position and a method of forming a pattern. 

## DETAILED DESCRIPTION OF THE INVENTION 

Embodiments of the present invention will be described in detail below. 

Herein, the groups and atomic groups for which no state› ment is made as to substitution or nonsubstitution are to be interpreted as including those containing no substituents and also those containing substituents. For example, the "alkyl groups" for which no statement is made as to substitution or nonsubstitution are to be interpreted as including not only the 

alkyl groups containing no substituents (unsubstituted alkyl groups) but also the alkyl groups containing substituents (substituted alkyl groups). 

Further, the term "actinic rays" or "radiation" means, for example, brightline spectra from a mercury lamp, far ultra› violet represented by an excimer laser, extreme ultraviolet (EUV), X-rays and electron beams (EB). Herein, the term "light" means actinic rays or radiation. 

The term "exposure to light" unless otherwise specified means not only irradiation with light, such as light from a mercury lamp, far ultraviolet, X-rays or EUV light, but also lithography using particle beams, such as electron beams and ion beams. 

The actinic-ray- or radiation-sensitive resin composition of the present invention comprises, specified below, a resin (Aa) containing repeating units (Aal) and (Aa2) and a resin (Ab) that when acted on by an acid, changes its alkali solubility. 

## [Resin (Aa)] 

The resin (Aa) contains at least one repeating unit (Aal) derived from monomers of general formula (aal-1) below and at least one repeating unit (Aa2) derived from monomers of general formula ( aa2-1) below. The incorporation of the resin (Aa) in the composition of the present invention exerts the effect of improving development defects. One reason therefor would be that a fluorinated ester group existing at, for example, an end of a side chain of the resin is hydrolyzed by an alkali developer to thereby render the resin hydrophilic. Further, the incorporation of the resin (Aa) in the composition of the present invention exerts the effect of enhancing dry etching resistance. One reason therefor would be the presence of a benzene ring in the repeating unit (Aa2). 

<img src='content_image/896919.jpg'>

<img src='content_image/896920.jpg'>

In general formula (aal-1), 

Q$_{1 }$represents an organic group containing a polymerizable group. 

Each ofL$_{1 }$ and L$_{2 }$ independently represents a single bond or a bivalent connecting group. 

Rf represents an organic group containing a fluorine atom. 

In general formula (aa2-1), 

Rb represents a hydrogen atom, an optionally substituted alkyl group, or a halogen atom. 

S$_{1}$a, when two or more S$_{1}$as exist, each independently, represents a substituent, and 

pis an integer of0 to 5. 

First, the repeating units (Aal) derived from monomers of general formula (aal-1) will be described. 

