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[Chemical Formula 99] 

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Using each of the obtained resist compositions, the follow› ing evaluations were performed. 

[Formation of Resist Pattern] 

Using a spinner, the resist composition of each example was applied uniformly onto an 8-inch silicon substrate that had been surface-treated withhexamethyldisilazane (HMDS) for36 seconds at 90° C., and a bake treatment (P AB)was then conducted for 60 seconds at a PAB temperature shown in Table 4, thereby forming a resist film (thickness: 60 nm). This resist film was subjected to patterning (exposure) with an electron beam exposure apparatus HL800D (VSB) (manufac› tured by Hitachi Ltd.) using an accelerating voltage of 50 ke Y, and was then subjected to a bake treatment (PEB) for 60 seconds at a PEB temperature shown in Table 4, followed by development for 60 seconds at 23° C. in a 2.38% by weight aqueous solution of tetramethylammonium hydroxide (TMAH) (product name: NMD-3, manufactured by Tokyo Ohka Kogyo Co., Ltd.). 

As a result, in each example, a line and space resist pattern (hereafter referred to as an "L/pattern") having a line width of 100 nm and a pitch of 200 nm was formed. 

-continued 

It is thought that a higher accelerating voltage is advanta› geous in forming a fine resist pattern, but in the present evaluation, in order to reproduce a state that simulates the state in which OoB light is generated, a comparatively low accelerating voltage of 50 keV was employed for the expo› sure conditions. 

[Evaluation of Sensitivity and Resolution] 2 

The optimum exposure dose Eop (µC/cm ) at which an LIS pattern having a line width of 100 nm and a pitch of 200 nm was formed in the aforementioned "Formation of Resist Pat› tern" was determined and recorded as the sensitivity. The results are listed in Table 4. 

Further, the resolution limit at the above Eop value was also determined. The results are shown in Table 4 as "resolution". [Evaluation of Line Edge Roughness (LER)] 

For the LS pattern formed in the aforementioned "Forma› tion of Resist Pattern", the value of 3a was determined as a measure of the LER. This value of3a (units: nm) represents the value of three times the standard deviation ( a) for line width values measured at 400 points along the lengthwise direction of the line using a scanning electron microscope (product name: S-9220, manufactured by Hitachi High-Tech› nologies Corporation, accelerating voltage: 800 V). The smaller the value of3a, the lower the level of roughness in the line side walls, meaning an LS pattern of more uniform width has been obtained. The results are shown in Table 4. 

[Evaluation of Cross-Sectional Shape] 

Using a scanning electron microscope (product name: SU8000, manufactured by Hitachi High-Technologies Cor› poration, accelerating voltage: 800 V), the cross-sectional shape of an LS pattern having a line width of 100 nm and a pitch of200 nm formed in the aforementioned "Formation of Resist Pattern" was inspected. Patterns for which the cross› sectional shape was rectangular were evaluated as "A", whereas patterns having a rounded top shape were evaluated as "B". The results are shown in Table 4. 

[Evaluation of Sensitivity to KrF Excimer Laser Light (Ea Measurement)] 

Using a spinner, the resist composition of each example was applied uniformly onto an 8-inch silicon substrate that had been surface-treated withhexamethyldisilazane (HMDS) for 36 seconds at 90° C., and a bake treatment (PAB) was then conducted for 60 seconds at a PAB temperature shown in Table 4, thereby forming a resist film (thickness: 60 nm). This resist film was subjected to exposure using a KrF exposure apparatus S-203B (manufactured by Nikon Corporation), and was then subjected to a bake treatment (PEB) for 60 seconds at a PEB temperature shown in Table 4, followed by devel› opment for 60 seconds at 23 ° C. in a 2.38% by weight aqueous solution of tetramethylammonium hydroxide (TMAH) (product name: NMD-3, manufactured by Tokyo Ohka Kogyo Co., Ltd.). 

The above operation was performed while the exposure dose was changed (increased in a stepwise manner from Oto 50 mJ/cm 2 ), and the lowest exposure dose (mJ/cm 2 ) at which the resist film within the exposed portions was removed was recorded as the Ea sensitivity. Compositions for which the resist film within the exposed portions was not removed even when the exposure dose reached 50 mJ/cm 2 , namely compo› sitions for which the value of the Ea sensitivity exceeded 50 mJ/cm 2 , were deemed to have no sensitivity to KrF excimer laser light. The results are shown in Table 4. In Table 4, "N.D." indicates that the composition lacked sensitivity to KrF exci› mer laser light. 

