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[1189] <Evaluation of Lithography Properties (l)> 

[1190] [Resolution and Sensitivity] 

[1191] An organic anti-reflection film composition (prod› uct name: ARC95, manufactured by Brewer Science Ltd.) was applied to an 12-inch silicon wafer using a spinner, and the composition was then baked at 205° C. for 90 seconds, thereby forming an organic anti-reflection film having a film thickness of 90 nm. 

[1192] Then, each positive resist composition obtained in Examples 1 to 3 and Comparative Examples 1 to 4 was applied onto the anti-reflection film using a spinner, and was then prebaked (PAB) on a hotplate at a temperature indicated in Table 3 for 60 seconds and dried, thereby forming a resist film having a film thickness of 80 nm. 

[1193] Subsequently, a coating solution for forming a pro› tection film (product name: TILC-057; manufactured by Tokyo Ohka Kogyo Co., Ltd.) was applied to the resist film using a spinner, and then heated at 90° C. for 60 seconds, thereby forming a top coat with a film thickness of 35 nm. 

[1194] Subsequently, the resist film was selectively irradi› ated with an ArF excimer laser (193 nm) through a mask, using an ArF immersion exposure apparatus NSR-S609B (manufactured by Nikon Corporation, NA (numerical aper› ture )=1.07, Dipole 0.78/0.97). 

[1195] Next, a post exposure bake (PEB) treatment was conducted at a temperature indicated in Table 3 for 60 sec› onds, followed by alkali development for 10 seconds at 23 ° C. in a 2.38% by weight aqueous TMAH solution (product name: NMD-3; manufactured by Tokyo Ohka Kogyo Co., Ltd.). Then, the resist was washed for 25 seconds with pure water, followed by drying by shaking. Finally, a bake treat› ment (post bake) was conducted at 100° C. for 45 seconds. 

[1196] As a result, in each of the examples, a line and space pattern (hereafter, referred to as "LS pattern") having a line width of 50 nm and a pitch of 100 nm was formed. 2 

[1197] The optimum exposure dose (Eop mJ/cm ) with which the pattern was formed, i.e., sensitivity, was deter› mined. The results are shown in Table 3. 

[1198] [Evaluation of Line Width Roughness (LWR)] 

[1199] With respect to each of the LS patterns formed with the above Eop and having a line width of 50 nm and a pitch of 100 nm, the line width at 400 points in the lengthwise direc› tion of the line were measured using a measuring scanning electron microscope (SEM) (product name: S-9220, manu› factured by Hitachi, Ltd.; acceleration voltage: SOOY). From the results, the value of3 times the standard deviations (i.e., 3s) was determined, and the average of the 3s values at 5 points was calculated as a yardstick of LWR. The results are shown in Table 3. 

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(A)-3: a copolymer represented by chemical formula (Al ’-11-1) shown below withMw = 7,000 and Mwl1v1n = 1. 7. In the formula, the subscript numerals shown to the bottom right of the parentheses () indicate the percentage (mo1%) of the respective structural units within the copolymer. [Chemical Formula 121] 

[1200] The smaller this 3s value is, the lower the level of roughness of the line width, indicating that a LS pattern with a uniform width was obtained. 

[1201] [Evaluation of Line Edge Roughness (LER)] 

[1202] The LER of the LS pattern having a line width of 50 nm and a pitch of 100 nm was determined. 

[1203] Specifically, using a measuring scanning electron microscope (SEM) (product name: S-9360, manufactured by Hitachi, Ltd.; measurement voltage: 300V), deviation from the average line of the line edge in each resist pattern was measured at 400 points. From the results, the value of3 times the standard deviation s (i.e., 3s) was determined, and the average of the 3s values at 5 points was calculated as a yardstick ofLER. The results are shown in Table 3. 

[1204] The smaller the determined value is, the lower the level of roughness of the line width, indicating that a LS pattern with a uniform width was obtained. 

[1205] [Evaluation of Resist Pattern Shape] 

[1206] With respect to each LS pattern having a line width of 50 nm and a pitch of 100 nm, the cross-sectional shape of the resist pattern was observed using a scanning electron microscope (product name: S-4700, manufactured by Hita› chi, Ltd.) The results are shown in Table 3. 

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[1207] From the results shown in Table 3, it was confirmed that the resist compositions of Examples 1 to 3 according to the present invention exhibited excellent properties with respect to LWR, LER and resist pattern shape, as compared to the resist compositions of Comparative Examples 1 to 4. 

[1208] The components shown in Table 4 were mixed together and dissolved to obtain positive resist compositions. 

[1209] In Table 4, the reference characters indicate the fol› lowing. Further, in Table 4, the values in brackets [ ] indicate the amount (in terms of parts by weight) of the component added. 

## Production of Resist Composition (2) 

## Example 4, Comparative Example 5 

