Acid generating agent for chemically amplified resist compositions

An acid generating agent represented by the following formula 2:

• wherein X represents an unsubstituted or substituted alkyl group having 1 to 20 carbon atoms and selected from alkyl, haloalkyl and alkylsulfonyl, which may have at least one hydrogen atom substituted by an ether group, an ester group, a carbonyl group, an acetal group, a nitrile group, a cyano group, a hydroxyl group, a carboxyl group or an aldehyde group, or represents a perfluoroalkyl group having 1 to 4 carbon atoms;
• R6 represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a heteroatom selected from N, S, F and O;
• m is an integer from 0 to 2;
• and A+ is an organic counterion.

A compound represented by the following formula (10):

• wherein X represents an unsubstituted or substituted alkyl group having 1 to 20 carbon atoms and selected from alkyl, haloalkyl and alkylsulfonyl, which may have at least one hydrogen atom substituted by an ether group, an ester group, a carbonyl group, an acetal group, a nitrile group, a cyano group, a hydroxyl group, a carboxyl group or an aldehyde group, or represents a perfluoroalkyl group having 1 to 4 carbon atoms;
• R6 represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a heteroatom selected from N, S, F and O;
• m is an integer from 0 to 2;
• and M is Li, Na or K.