Positive working resist composition

1. A positive working resist composition comprising (A1) a resin containing a repeating unit represented by formula (1) shown below and a repeating unit represented by formula (2) shown below and having a property of being insoluble or sparingly soluble in an alkali developing solution and becoming soluble in an alkali developing solution by the action of an acid, (B) a compound capable of generating sulfonic acid upon irradiation with active rays or radiations in an amount of from 5 to 20% by weight based on the total solid content of the positive working resist composition, and (D) a compound capable of generating a carboxylic acid upon irradiation with active rays or radiations in an amount of from 0.05 to 3% by weight based on the total solid content of the positive working resist composition:

wherein R 1 represents a hydrogen atom, a methyl group, a cyano group, a halogen atom or a perfluoroalkyl group having from 1 to 4 carbon atoms; R 2 represents a hydrogen atom, an alkyl group, a halogen atom, an aryl group, an alkoxy group or an acyl group; R 3 and R 4 each independently represent a hydrogen atom or an alkyl group having from 1 to 4 carbon atoms; Z represents a hydrocarbon group having from 6 to 30 carbon atoms and containing at least one cyclic structural unit selected from an alicyclic structure, an aromatic cyclic structure and a bridged alicyclic structure; and n represents an integer of from 0 to 4.

2. The positive working resist composition according to claim 1 , which further comprises (C) a nitrogen-containing basic compound.

3. The positive working resist composition according to claim 1 , which further comprises (A2) a resin containing a repeating unit represented by formula (2) below and a repeating unit represented by formula (3) below and having a property of being insoluble or sparingly soluble in an alkali developing solution and becoming soluble in an alkali developing solution by the action of an acid:

wherein R 1 represents a hydrogen atom, a methyl group, a cyano group, a halogen atom or a perfluoroalkyl group having from 1 to 4 carbon atoms; R 2 represents a hydrogen atom, an alkyl group, a halogen atom, an aryl group, an alkoxy group or an acyl group; R 3 and R 4 each independently represent a hydrogen atom or an alkyl group having from 1 to 4 carbon atoms; Z 1 represents a hydrocarbon group having from 1 to 5 carbon atoms; and n represents an integer of from 0 to 4.

4. The positive working resist composition according to claim 1 , wherein an amount of the compound (B) capable of generating sulfonic acid upon irradiation with active rays or radiations is from 7 to 16% by weight based on the total solid content of the positive working resist composition.

5. The positive working resist composition according to claim 1 , wherein the resin (A1) contains the repeating unit represented by formula (1), the repeating unit represented by formula (2) and a repeating unit represented by the following formula (4):

wherein, R 1 , R 2 , and n have the same meanings as R 1 , R 2 , and n in formula (1), respectively; and W represents a group that is not decomposed by the action of an acid.

6. The positive working resist composition according to claim 3 , wherein the resin (A2) contains the repeating unit represented by the formula (2), the repeating unit represented by the formula (3) and a repeating unit represented by the formula (4):

wherein, R 1 , R 2 , and n have the same meanings as R 1 , R 2 , and n in formula (2), respectively; and W represents a group that is not decomposed by the action of an acid.

7. The positive working resist composition according to claim 1 , which further comprises a fluorine based and/or silicon based surfactant.

8. The positive working resist composition according to claim 1 , wherein the weight ratio of the compound (D) capable of generating a carboxylic acid upon irradiation with active rays or radiations/the compound (B) capable of generating a sulfonic acid is 0.1/99.9 to 50/50.

9. The positive working resist composition according to claim 1 , wherein the weight ratio of the compound (D)/the compound (B) is 1/99 to 40/60.

10. The positive working resist composition according to claim 1 , wherein the weight ratio of the compound (D)/the compound (B) is 2/98 to 30/70.