Pattern-forming method and composition

1. A pattern-forming method comprising:

forming a base pattern having recessed portions on a front face side of a substrate directly or via other layer;

filling the recessed portions of the base pattern with a first composition to form a filler layer, the first composition comprising: a first polymer comprising at least two blocks; and a solvent;

allowing phase separation of the filler layer to form a plurality of phases of the filler layer;

removing a part of the plurality of phases of the filler layer to form a miniaturized pattern; and

etching the substrate by directly or indirectly using the miniaturized pattern as a mask,

wherein the forming of the base pattern comprises:

forming a resist pattern on the front face side of the substrate;

forming a layer of a second polymer on lateral faces of the resist pattern; and

forming a layer of a third polymer that differs from the second polymer on a surface of the substrate or on a surface of the other layer.

2. The pattern-forming method according to claim 1 , wherein

each of the substrate and the other layer comprises on upper faces thereof, at least one of Si—H, Si—OH, Si═O and Si—NR 2 , wherein each R independently represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms,

the resist pattern comprises at least one of —COOH and —OH on a lateral face thereof,

the second polymer comprises a first functional group that bonds to at least one end of a main chain thereof and is capable of forming a chemical bond with at least one of —COOH and —OH, and

the third polymer comprises a second functional group that bonds to at least one end of a main chain thereof and is capable of forming a chemical bond with at least one of Si—H, Si—OH, Si═O and Si—NR 2 .

3. The pattern-forming method according to claim 1 , wherein the forming of layers of the second polymer comprises: applying a second composition comprising the second polymer and a solvent; and the forming of layers of the third polymer comprises: applying a third composition comprising the third polymer and a solvent.

4. The pattern-forming method according to claim 1 , wherein each of the forming of layers of the second polymer and the forming of the third polymer comprises applying a fourth composition comprising the second polymer, the third polymer and a solvent.

5. The pattern-forming method according to claim 3 , wherein the forming of the base pattern is carried out in order of: the forming of the resist pattern; the applying of the second composition; and the applying of the third composition.

6. The pattern-forming method according to claim 3 , wherein the forming of the base pattern is carried out in order of: the applying of the third composition; the forming of the resist pattern; and the applying of the second composition.

7. The pattern-forming method according to claim 4 , wherein the forming of the base pattern comprises:

the forming of the resist pattern; and

the applying of the fourth composition after the forming of the resist pattern.

8. The pattern-forming method according to claim 1 , wherein the forming of the resist pattern comprises:

applying a resist composition comprising a polymer comprising an acid-labile group, and radiation-sensitive acid generator;

exposing the applied resist composition; and

developing the exposed resist composition with a developer solution comprising an organic solvent.

9. The pattern-forming method according to claim 1 , wherein the forming of the resist pattern comprises:

applying a resist composition comprising a polymer comprising an acid-labile group, and radiation-sensitive acid generator;

exposing the applied resist composition;

developing the exposed resist composition with an alkaline developer solution; and

heating or exposing the developed resist composition.

10. The pattern-forming method according to claim 1 , wherein the substrate or the other layer is made from SiO 2 or SiN.

11. The pattern-forming method according to claim 1 , wherein the other layer is a silicon-containing film.

12. The pattern-forming method according to claim 2 , wherein the first functional group is a hydroxyl group, an epoxy group or an oxetanyl group.

13. The pattern-forming method according to claim 2 , wherein the second functional group is a carboxy group, a hydroxyl group or a halogen atom.

14. The pattern-forming method according to claim 1 , wherein the first polymer is a diblock polymer comprising a polystyrene block and a (meth)acrylic acid ester block.

15. The pattern-forming method according to claim 1 , wherein a hole pattern is formed.

16. A pattern-forming method comprising:

overlaying a base pattern having recessed portions on a front face side of a substrate directly or via other layer;

applying a fifth composition on lateral faces and bottom faces of the recessed portions of the base pattern to form a coating film;

heating the coating film;

filling with a sixth composition, the recessed portions of the base pattern overlaid with the coating film, to form a filler layer;

allowing phase separation of the filler layer to form a plurality phases of the filler layer;

removing a part of the plurality phases of the filler layer to form a miniaturized pattern; and

etching the substrate once or several times using the miniaturized pattern as a mask,

wherein

the base pattern comprises as a principal component a polymer comprising aromatic rings, a content of the aromatic rings being no less than 50% by mass with respect to the polymer,

the fifth composition comprises: a fourth polymer comprising a first structural unit; and a solvent,

the sixth composition comprises: a fifth polymer; and a solvent, the fifth polymer comprising a first block comprising a second structural unit, and a second block comprising a third structural unit that is more polar than the second structural unit, and

a difference in contact angles (|θ1-θ2|) is no less than 5°, wherein θ1 is a contact angle of the coating film with water on a lateral face side in the recessed portions and θ2 is a contact angle of the coating film with water on a bottom face side in the recessed portions, provided that θ1 and θ2 are measured after the heating of the coating film.

17. The pattern-forming method according to claim 16 , wherein the first structural unit and the second structural unit are both derived from substituted or unsubstituted styrene.

18. The pattern-forming method according to claim 16 , wherein

in the overlaying, the base pattern is directly overlaid on the front face side of the substrate, and

the substrate is made from silicon.

19. The pattern-forming method according to claim 16 , wherein a temperature or a time period is controlled in the heating of the coating film.

20. The pattern-forming method according to claim 16 , wherein the base pattern is a hole pattern.