Positive photosensitive composition and pattern forming method using the same

1. A positive photosensitive composition comprising:

(A) a compound capable of generating an acid upon irradiation with actinic rays or radiation;

(B1) a resin of which solubility in an alkali developer increases under an action of an acid; and

(B2) a resin that has a group capable of decomposing under an action of an alkali to produce an alkali-soluble group, and the resin (B2) does not have a group capable of decomposing under an action of an acid,

wherein the group capable of decomposing under an action of an alkali to produce an alkali-soluble group is a lactone having any one of the following structures:

wherein each ring may have a substituent.

2. The positive photosensitive composition according to claim 1 ,

wherein the resin as the component (B1) has a monocyclic or polycyclic hydrocarbon structure.

3. The positive photosensitive composition according to claim 1 ,

wherein the resin as the component (B1) has a hydroxystyrene structural unit.

4. The positive photosensitive composition according to claim 1 ,

wherein the resin as the component (B1) has a repeating unit having a polycyclic hydrocarbon group substituted by a hydroxyl group or a cyano group.

5. The positive photosensitive composition according to claim 1 ,

wherein the compound as the component (A) is a compound capable of generating an acid selected from the group consisting of an acid having a fluoroalkylsulfonic acid structure with a carbon number of 2 to 4, a bis(fluoroalkylsulfonyl)imide acid and a fluorine atom-containing benzenesulfonic acid upon irradiation with actinic rays or radiation.

6. The positive photosensitive composition according to claim 1 ,

wherein the resin as the component (B1) contains a repeating unit having a lactone group.

7. The positive photosensitive composition according to claim 1 ,

wherein the resin as the component (B2) is a resin consisting of a repeating unit having a lactone group or a copolymer resin containing 50 mol % or more of a repeating unit having a lactone group.

8. The positive photosensitive composition according to claim 1 ,

wherein an amount added of the resin as the component (B2) is from 1 to 20 mass % based on that of the resin as the component (B1).

9. A pattern forming method comprising:

forming a photosensitive film from a positive photosensitive composition according to claim 1 ; and

exposing and developing the photosensitive film.

10. A method for performing an immersion exposure comprising:

forming a photosensitive film from a positive photosensitive composition according to claim 1 ; and

immersion exposing and developing the photosensitive film.

11. The positive photosensitive composition according to claim 1 , wherein the weight average molecular weight of the resin as component (B2) is from 1,000 to 100,000.

12. The positive photosensitive composition according to claim 11 , wherein the weight average molecular weight of the resin as component (B2) is from 2,000 to 50,000.

13. The positive photosensitive composition according to claim 12 , wherein the weight average molecular weight of the resin as component (B2) is from 3,000 to 20,000.

14. A positive photosensitive composition comprising:

(A) a compound capable of generating an acid upon irradiation with actinic rays or radiation;

(B1) a resin of which solubility in an alkali developer increases under an action of an acid; and

(B2) a resin that has an alkali-soluble group selected from the group consisting of an aliphatic hydroxyl group with a carbon atom at 1- or 2-position being substituted by an electron withdrawing group, an electron withdrawing group-substituted amino group, and an electron withdrawing group-substituted methylene or methine group, and the resin (B2) does not have a group capable of decomposing under an action of an acid,

wherein the component (B2) has an alkali-soluble group of the following structure:

15. The positive photosensitive composition according to claim 14 ,

wherein the resin as the component (B1) has a monocyclic or polycyclic hydrocarbon structure.

16. The positive photosensitive composition according to claim 14 ,

wherein the resin as the component (B1) has a hydroxystyrene structural unit.

17. The positive photosensitive composition according to claim 14 ,

wherein the resin as the component (B1) has a repeating unit having a polycyclic hydrocarbon group substituted by a hydroxyl group or a cyano group.

18. The positive photosensitive composition according to claim 14 ,

wherein the compound as the component (A) is a compound capable of generating an acid selected from the group consisting of an acid having a fluoroalkylsulfonic acid structure with a carbon number of 2 to 4, a bis(fluoroalkylsulfonyl)imide acid and a fluorine atom-containing benzenesulfonic acid upon irradiation with actinic rays or radiation.

19. The positive photosensitive composition according to claim 14 ,

wherein the resin as the component (B1) contains a repeating unit having a lactone group.

20. The positive photosensitive composition according to claim 14 ,

wherein an amount added of the resin as the component (B2) is from 1 to 20 mass % based on that of the resin as the component (B1).

21. A pattern forming method comprising:

forming a photosensitive film from a positive photosensitive composition according to claim 14 ; and

exposing and developing the photosensitive film.

22. A method for performing an immersion exposure comprising:

forming a photosensitive film from a positive photosensitive composition according to claim 14 ; and

immersion exposing and developing the photosensitive film.

23. The positive photosensitive composition according to claim 14 , wherein the weight average molecular weight of the resin as component (B2) is from 1,000 to 100,000.

24. The positive photosensitive composition according to claim 23 , wherein the weight average molecular weight of the resin as component (B2) is from 2,000 to 50,000.