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## Examples 2-1 to 2-14 and Comparative Examples 2-1 to 2-7 

Resist Test 1 (ArF Lithography) 

On a silicon substrate, an antireflective coating solution (ARC-29A, Nissan Chemical Industries, Ltd.) was coated and baked at 200° C. for 60 seconds to form an ARC of 100 nm thick. Each of the resist solutions shown in Table 4 was spin coated on the silicon substrate and baked on a hot plate at 100° C. for 60 seconds, forming a resist film of 90 nm thick on the ARC. The wafer was exposed on an ArF excimer laser immersion lithography scanner (NSR-S610C by Nikon Corp., NA 1.30, dipole illumination, Cr mask), baked (PEB) at 80° C. for 60 seconds, and developed in a 2.38 wt% tetramethylammonium hydroxide (TMAH) aque- ous solution for 60 seconds, forming a pattern. 

Resist evaluation was made on a 40-nm 1:1 line-and- space pattern. On observation under an electron microscope, the optimum exposure dose (Eop) was defined as an expo- sure dose (mJ/cm 2 ) which provided a line width of 40 nm. 

The width of lines of a 40-nm 1: 1 line-and-space pattern was measured under SEM to determine a line width varia- tion (30 points measured, 3a value computed), which was reported as line width roughness (LWR). A smaller value of LWR indicates a line pattern with a less fluctuation and of better profile. In this test, the sample is rated good when LWR is equal to or less than 3.0 nm and poor when LWR is equal to or more than 3 .1 nm. 

An LIS pattern was formed by exposure in the optimum dose (determined in the sensitivity evaluation) through the mask with the pitch fixed and the line width varied. MEF was calculated from variations of the mask line width and the pattern space width according to the following equation: 

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wherein b is a constant. A value closer to unity (1) indicates better performance. 

Further, for a trench pattern printed at the optimum exposure dose, the dependency of trench size on focus was examined. A range (nm) of focus capable of resolution was determined and reported as DOF. 

The collapse limit was a minimum width (nm) of lines which could be resolved without collapse when the line 

width was reduced by increasing the exposure dose. A smaller value indicates better collapse resistance. 

The results of evaluation are shown in Table 5. 

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As seen from the results of Table 5, the resist composi- tions within the scope of the invention offer advantages including improved LWR, MEF, DOF, and collapse limit, and are suited as resist material for ArF immersion lithog- raphy. 

## Examples 3-1 to 3-14 and Comparative Examples 3-1 to 3-7 

Resist Test 2 (ArF Lithography) 

On a substrate, a spin-on carbon film ODL-50 (Shin-Etsu Chemical Co., Ltd.) having a carbon content of 80 wt% was deposited to a thickness of 200 nm and a silicon-containing spin-on hard mask SHB-A940 having a silicon content of 43 wt% was deposited thereon to a thickness of35 nm. On this 

