Chemical amplification resist composition, and mold preparation method and resist film using the same

A method for preparing a mold, comprising:

• coating a chemical amplification resist composition on a substrate to form a resist film,
• performing pattern drawing with an electron beam,
• performing development with a developer to form a resist pattern;
• performing an etching treatment to the substrate having thereon the thus-formed resist pattern by using the resist pattern as a mask to form a concave-convex structure on the substrate,
• wherein
• the chemical amplification resist composition comprises:
• (A) a resin capable of decomposing by an action of an acid to increase the solubility of the resin (A) in an alkali developer,
• wherein the resin (A) has a group represented by the following formula (I) or (II):
• wherein each of R1 and R2 independently represents a hydrogen atom or an alkyl group;
• W represents a divalent organic group;
• and
• R3 represents an alkyl group, a cycloalkyl group, an aryl group or an aralkyl group:
• wherein R1, R2 and W have the same meanings as those in formula (I);
• and
• R4 represents a cycloalkyl group or an aryl group.