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ing power (run) was defined as the limiting resolving power (minimum line width permitting the separation and resolu› tion of a line and a space (line:space=l: 1 )) in the exposure amount in which a 50 run line width 1: 1 line and space resist pattern was resolved. 

[Pattern Shape] 

The shape of cross section of each 50 run line width 1: 1 line and space pattern in the exposure amount exhibiting the above sensitivity was observed by means of a scanning electron microscope (model S-4300, manufactured by Hitachi, Ltd.). The shape of cross section of each line pattern when the ratio of [line width of line pattern at its top portion (surface portion)/line width of line pattern at its middle portion (position at half of the height of the line pattern)] was 1.2 or greater was graded into "inverted taper"; that when the ratio was in the range of 1.05 to less than 1.2 was graded into "slightly inverted taper"; and that when the ratio was less than 1.05 was graded into "rectangle." 

[Line Edge Roughness (LER)] 

A 50 run line width 1: 1 line and space pattern was formed in the exposure amount exhibiting the above sensitivity. At arbitrary 30 points within 50 µmin the longitudinal direction of the pattern, the distance between actual edge and a reference line on which edges were to be present was measured by means of a scanning electron microscope (model S-9220, manufactured by Hitachi, Ltd.). The stan› dard deviation of measured distances was determined, and 3a was computed therefrom. The smaller the value thereof, the more favorable the performance exhibited. 

[Dependence on PEB Temperature] 

The optimum exposure amount was defined as the expo› sure amount in which a 1: 1 line and space of 50 run mask size was reproduced upon post-exposure bake (PEB) at 110° C. for 90 seconds. The exposure in the optimum exposure 55 amount was followed by subsequent bakes at two tempera› tures, one being the above temperature+2° C. (namely 112° C.) and the other being the above temperature-2° C. (namely 108° C.). The resultant line and space patterns were measured, thereby determining line width L1 and line width 60 L2 thereof. The dependence on PEB temperature (PEBS) was defined as the variation of line width per PEB tempera› ture change 1 ° C., and was calculated by the following formula: 

Dependence on PEB temperature (nm/ 0 C.)~IL1- L21/4 

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The smaller the value, the more favorably smaller the performance change by temperature change. 

[Evaluation of PED (Post-Exposure Time Delay) Stabil› ity] 

Exposure was performed in the exposure amount in which the dimension of the 50 run line width 1: 1 line and space pattern was 50 run. Immediately thereafter, PEB was per› formed, and the line width dimension (0 h) was measured. Separately, PEB was performed two hours after the expo- lO sure, and the line width dimension (2.0 h) on the wafer was measured. The line width change ratio was calculated by the following formula: 

Line width change ratio (%)~L\.CD(2.0 h-0 h)nm/50 nm 

The smaller the value, the more favorable the perfor› mance exhibited. The value was used as an index of PED stability. 

From the results of Table 4, it is apparent that the compositions of the present invention exhibit enhanced sensitivity, resolving power, pattern shape and LER perfor› mance, and realizes low dependence on PEB temperature and excellent PED stability, in the exposure to EUV. 

## Examples 1 C to 6C and Comparative Examples 1 C and 2C: Exposure to EB; Negative; Organic Solvent Development 

(1) Preparation of Resist Composition and Formation of Resist Film 

Each of the compositions indicated in Table 5 below was precision filtered through a membrane filter of 0.1 µm pore diameter, thereby obtaining a resist composition. 

Each of the obtained resist compositions was applied onto a 6-inch Si wafer having been treated with hexamethyldisi› lazane (HMDS) by means of a spin coater Mark 8 manu› factured by Tokyo Electron Limited, and dried on a hot plate at 100° C. for 60 seconds, thereby obtaining a 50 run-thick resist film. 

(2) Exposure to EB and Development 

Each of the wafers coated with resist films that were obtained in section (1) above was patternwise exposed to electron beams by means of an electron beam lithography system (HL 750 manufactured by Hitachi, Ltd., acceleration voltage 50 KeV). The lithography was performed so as to 

