Water soluble resin composition and method for pattern formation using the same

1. A water soluble resin composition for use in a semiconductor manufacturing process, where said water soluble resin composition comprises a water soluble resin, an acid generating agent capable of generating an acid upon heating, a crosslinking agent, and a water-containing solvent, wherein said acid generating agent is represented by formula

wherein

R 0 represents —C n H 2n+1−m F m where n is 1 to 20 and m is 0 to 2n+1,

where R′ is —(CH 2 ) x CH 3 , —OH, or —COOH in which x is 0 to 20; and

R 1 , R 2 , R 3 , and R 4 each independently represent —H, C p H 2p+1 , or —C p H 2p OH where p is 1 to 10.

2. The water soluble resin composition according to claim 1 , wherein said water soluble resin comprises a copolymer of N-vinylpyrrolidone with vinylimidazole.

3. The water soluble resin composition according to claim 1 , which further comprises at least one surfactant selected from the group consisting of acetylenic alcohols, acetylenic glycols, polyethoxylates of acetylenic alcohols, and polyethoxylates of acetylenic glycols.

4. The water soluble resin composition according to claim 1 , wherein said water-containing solvent consists of water alone, or a mixture of water with a water soluble organic solvent.

5. The water soluble resin composition according to claim 1 , wherein said crosslinking agent is an alkylated urea, oxazoline group-containing polymer, or polyamines.

6. The water soluble resin composition according to claim 1 , which comprises, based on 100 parts by weight of the water soluble resin composition, 1 to 30 parts by weight of the water soluble resin, 0.01 to 10 parts by weight of the acid generating agent.

7. A method for pattern formation, comprising the steps of: coating the water soluble resin composition according claim 1 onto a resist pattern formed of a radiation-sensitive resin composition capable of coping with ArF exposure to form a covering layer; heating the covering layer to crosslink the covering layer in its part with a predetermined thickness located near the resist pattern to form a modified covering layer insoluble in a developing solution; and developing the modified covering layer to form a pattern in which the surface of the resist pattern has been covered with the modified covering layer.

8. The method of claim 7 , where the modified covering layer has a film thickness in the range of 0.01 to 100 μm.

9. A pattern covered with a modified covering layer, which is composed of resist pattern formed of a radiation-sensitive resin composition capable of coping with ArF exposure and the modified covering layer formed on the surface of the resist pattern, wherein the modifiedcovering layer is formed by coating the water soluble resin composition according to claim 1 onto the resist pattern to form a covering layer, by heating the covering layer located near the resist pattern to crosslink in its part with a predetermined thickness to form the modified covering layer insoluble in a developing solution and by developing the modified covering layer to form the pattern.

10. The pattern of claim 9 , where the modified covering layer has a film thickness in the range of 0.01 to 100 μm.

11. The composition of claim 1 , where the water soluble resin has the structure,

wherein R a and R b each independently represents a hydrogen atom or a methyl group; R c represents —OH, —COOH, —OCOR d , where R d represents an alkyl group, or

and a and b each independently are 10 to 100,000.