Photosensitive composition, compound used in the same, and patterning method using the same

1. A photosensitive composition, comprising

(A) a sulfonium salt represented by formula (I);

wherein Y 1 , Y 2 and Y 3 each independently represents a nitrogen-containing heteroaryl group, an alkyl group, a cycloalkyl group, an aryl group or an alkenyl group, at least one of Y 1 , Y 2 and Y 3 represents a nitrogen-containing heteroaryl group, and at least two of Y 1 , Y 2 and Y 3 may combine with each other to form a ring; X n− represents an n-valent non-nucleophilic anion; and n represents an integer of 1 to 3.

2. A photosensitive composition according to claim 1 , wherein the nitrogen-containing heteroaryl group represented by Y 1 , Y 2 or Y 3 is a group selected from a pyrrolyl group, an indolyl group and a carbazolyl group.

3. A photosensitive composition according to claim 1 , wherein the sulfonium salt (A) represented by formula (I) is a sulfonium salt represented by formula (ID) or (IE);

wherein Ra 1 represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or an acyl group; Ra 2 and Ra 3 each independently represents an alkyl group, a cycloalkyl group, an aryl group or an alkenyl group, and Ra 2 and Ra 3 may combine with each other to form a ring; Ra 4 , or each of Ra 4 's when m is a plural number, independently represents an organic group; X 1 − represents a univalent non-nucleophilic anion; X 2 2− represents a divalent non-nucleophilic anion; and m represents an integer of 0 to 3.

4. A compound (A), represented by formula (I);

wherein Y 1 , Y 2 and Y 3 each independently represents a nitrogen-containing heteroaryl group, an alkyl group, a cycloalkyl group, an aryl group or an alkenyl group, at least one of Y 1 , Y 2 and Y 3 represents a nitrogen-containing heteroaryl group, and at least two of Y 1 , Y 2 and Y 3 may combine with each other to form a ring; X n− represents an n-valent non-nucleophilic anion; and n represents an integer of 1 to 3.

5. A patterning method, comprising:

forming a photosensitive film with a photosensitive composition according to claim 1 ;

exposing the photosensitive film to light, so as to form a exposed photosensitive film; and

developing the exposed photosensitive film.

6. A compound (A), represented by formula (ID) or (IE);

wherein Ra 1 represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or an acyl group; Ra 2 and Ra 3 each independently represents an alkyl group, a cycloalkyl group, an aryl group or an alkenyl group, and Ra 2 and Ra 3 may combine with each other to form a ring; Ra 4 , or each of Ra 4 's when m is a plural number, independently represents an organic group; X 1 − represents a univalent non-nucleophilic anion; X 2 2− represents a divalent non-nucleophilic anion; and m represents an integer of 0 to 3.

7. A photosensitive composition according to claim 1 , further comprising (B) a resin capable of decomposing under action of an acid to increase its solubility in an alkali developer.

8. A photosensitive composition according to claim 1 , further comprising:

(D) a resin soluble in an alkali developer; and

(E) an acid cross-linking agent capable of forming cross-links between molecules of the alkali developer-soluble resin under action of an acid.

9. A photosensitive composition according to claim 7 , wherein the resin (B) comprises hydroxystyrene structural units.

10. A photosensitive composition according to claim 7 , wherein the resin (B) comprises repeating units having monocyclic or polycyclic hydrocarbon structures.

11. A photosensitive composition according to claim 7 , wherein the resin (B) comprises repeating units having alcoholic hydroxyl groups.

12. A photosensitive composition according to claim 11 , wherein the repeating units having alcoholic hydroxyl groups are repeating units which each contain at least one structure selected from monohydroxyadamantane structures, dihydroxyadamantane structures and trihydroxyadamantane structures.

13. A photosensitive composition according to claim 7 , wherein the resin (B) comprises repeating units having lactone structures.

14. A photosensitive composition according to claim 7 , wherein the resin (B) comprises: repeating units derived from methacrylic acid esters of at least one kind; and repeating units derived from acrylic acid esters of at least one kind.

15. A photosensitive composition according to claim 7 , wherein the resin (B) comprises a fluorine atom.

16. A photosensitive composition according to claim 15 , wherein the resin (B) comprises a hexafluoro-2-propanol structure.

17. A photosensitive composition according to claim 7 , further comprising

(C) a dissolution-inhibiting compound having a molecular weight of 3,000 or below which can decompose under action of an acid to increase its solubility in an alkali developer.

18. A photosensitive composition according to claim 7 , further comprising a compound selected from:

(F) a basic compound; and

(G) a surfactant containing at least one of a fluorine atom and a silicon atom.

19. A photosensitive composition according to claim 7 , wherein the resin (B) comprises:

repeating units of at least one kind selected from 2-alkyl-2-adamantyl (meth)acrylates and dialkyl(1-adamantyl)methyl (meta)acrylates;

lactone structure-containing repeating units of at least one kind; and

repeating units of at least one kind which contain at least two hydroxyl groups per unit.

20. A photosensitive composition according to claim 7 , wherein the resin (B) comprises repeating units containing carboxyl groups.

21. A photosensitive composition according to claim 7 , wherein the resin (B) comprises:

repeating units of at least one kind selected from 2-alkyl-2-adamantyl (meth)acrylates and dialkyl(1-adamantyl)methyl (meta)acrylates; and

hydroxystyrene structure-containing repeating units of at least one kind.