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The mixture of the above-described each component was subjected to the microfiltration through a membrane filter having a pore size of 0.04 µm to obtain a resist coating solution. 

The resist coating solution was coated on the 6-inch wafer using a spin coater, Mark 8 available from Tokyo Electron Ltd., and dried on a hot plate at 110° C. for 90 seconds to 10 obtain a resist film having a film thickness of 100 nm. That is to say, resist coated mask blanks was obtained. 

This resist film was pattern-irradiated with electron beams by using an electron beam lithography apparatus (HL 750, available from Hitachi Ltd., accelerating voltage: 50 KeV). After the irradiation, the resist film was heated on a hot plate at 120° C. for 90 seconds, dipped for 60 seconds using 2.38% 20 by mass of an aqueous solution of tetramethylammonium hydroxide (TMAH), and then rinsed with water for 30 sec› onds and dried. 

The sensitivity, resolution, pattern profile, line edge rough› ness (LER) and dry etching resistance of the obtained pattern were evaluated by the following methods. 

## [Sensitivity] 

The cross-sectional profile of the obtained pattern was observed using a scanning electron microscope (S-4300, available from Hitachi Ltd.). The exposure amount (electron beam irradiation amount) in a case of resolving a resist pattern having a 100 nm line width (line:space=l:1) was defined as the sensitivity. The smaller this value, the higher the sensitiv› ity. 

## [Evaluation of Resolving Power (LS)] 

The limiting resolving power (the minimum line width when the line and the space (line:space=l:1) were separated and resolved) in the irradiation amount showing the afore› mentioned sensitivity ( electron beam irradiation amount) was defined as LS resolving power. 

## [Evaluation of Resolving Power (IL)] 

The limiting resolving power (the minimum line width when the line and the space (line:space=l:>100) were sepa› rated and resolved) in the minimum exposure amount in a case of resolving an independent line pattern having a 100 nm line width (line:space=l:>100) was defined as IL resolving power (nm). 

## [Pattern Profile] 

The cross-sectional profile of a line pattern having a 100 nm line width (LIS= 1/1) in the exposure amount showing the aforementioned sensitivity ( electron beam irradiation amount) was observed using a scanning electron microscope (S-4300, available from Hitachi Ltd.). In the cross-sectional profile of the line pattern, when the ratio represented by "the line width in the bottom part of the line pattern (bottom)/the lined width in the middle part of the line pattern (half height position of the height of the line pattern)" is 1.5 or more, it is evaluated as "tapered"; when the ratio is at least 1.2 less than 1.5, it is evaluated as "slightly tapered"; and when the ratio is less than 1.2, it is evaluated as "rectangular". 

## [Line Edge Roughness (LER)] 

The line pattern having a 100 nm line width (LIS= 1 /1) was formed in the irradiation amount showing the aforementioned sensitivity (electron beam irradiation amount). And, with 

## (3) Production of Resist Film 

## ( 4) Production of Positive Resist Pattern 

## (5) Evaluation of Resist Pattern 

respect to the region of 50 µmin the longitudinal direction of thereof, the distance from a reference line where the edge should be present was measured at arbitrary 30 points by a scanning electron microscope (S-9220, available from Hita- chi, Ltd.). In addition, the standard deviation of the distance was determined, and 36 was computed. It is shown that the smaller the value, the performance is better. 

## [Evaluation of Dry Etching Resistance] 

An unexposed resist film was subjected to dry etching using anAr/C$_{4}$ F$_{6}$ /0$_{2 }$ gas (a mixed gas having a volume ratio 100/4/2) for 30 seconds with HITACHI U-621. Thereafter, the residual film rate of the resist was measured and this value is used as an index of evaluating dry etching resistance. 

Very good: 95% or more of residual film rate 

Good: at least 90% less than 95% 

Poor: less than 90% 

## Example 2P to Example 22P, Comparative Example IP, and Comparative Example 2P 

Except for the components listed in the following Table 4, in the same manner as in Example IP, the preparation of the resist coating solutions (Positive Resist Compositions P2 to P22, Positive Resist Comparative Compositions Pl and P2), the production of positive resist patterns, and the evaluation thereof were performed. 

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