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From the results shown in Table 6, it can be seen that the composition according to the present invention have a good sensitivity, resolving power, pattern profile, LER and dry etching resistance. 

## (II) Example as a Positive Chemical Amplification Resist (EUV) 

## Examples 1 Q to SQ, and, Comparative Examples 1 Q and2Q 

The positive resist compositions shown in the following Table 7 were filtered through a polytetrafluoroethylene filter having a pore size of0.04 µm to obtain positive resist coating solutions. 

Evaluation of Resist Pattern 

The prepared positive resist coating solution was uni- formly coated on a hexamethyldisilazane-treated silicon sub› strate by using a spin coater and dried by heating on a hot plate at 100° C. for 60 seconds to obtain a resist film having a film thickness of0.05 µm. 

The sensitivity, resolving power, pattern profile, line edge roughness (LER) and dry etching resistance of the obtained resist film were evaluated by the following methods. 

[Sensitivity] 

As for the obtained resist film, an exposure was performed using EUV ray (13 nm of wavelength), while varying the exposure amount, within a range of from Oto 20.0 mJ/cm $^{2 }$in incrementof0.1 mJ/cm 2 , via 6%halftonemaskwitha 100nm line width having a line and space pattern of 1: 1, and there› after, baking was conducted at 110° C. for 90 seconds. There- after, the film was developed using 2.38% by mass of an aqueous solution of tetramethylammonium hydroxide (TMAH). 

The exposure amount reproducing mask pattern having a line and space of 100 nm line width (LIS=l/1) was defined as the sensitivity. The smaller this value, the higher the sensitiv› ity. 

## Preparation of Resist Coating Solution 

[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 exposure amount showing the aforemen- tioned sensitivity was defined as LS resolving power (nm). 

[Evaluation of 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 was observed using a scanning electron microscope (S-4300, available from Hitachi Ltd.). In the cross-sectional profile, when the ratio represented by "the line width in the bottom part of the line pattern (bottom)/the line 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)] 

With respect to the region of 50 µm in the longitudinal direction of a line pattern having a 100 nm line width (LIS= 1/ 1) in the exposure amount showing the aforementioned sen› sitivity, 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.), and the standard deviation was determined, and 3a 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% 

The results of the evaluation described above are shown in Table 7. 

