Gap filling composition and pattern forming method using composition containing polymer
[Subject] There is provided a gap filling composition which can reduce pattern collapse and a pattern forming method using the composition. [Solution means] There is provided a gap filling composition including a polymer having a certain structure and an organic solvent. There is provided a pattern forming method using a certain polymer.
1. A pattern forming method comprising:
(A1) a step of etching a layer to be processed to form a gap;
(A2) a step of filling a liquid into the gap;
(A3) a step of filling a composition comprising a polymer selected from the group consisting of polyethylene glycol, polypropylene glycol, polypropylene carbonate, polyethylene carbonate, polyethylene propylene glycol, and combination of two or more of these polymers and having a mass average molecular weight of not less than 1,000 and not more than 500,000 into said gap to replace said liquid; and
(A4) a step of removing said composition by heating.
2. The method according to claim 1 , wherein said composition is a gap filling composition comprising:
the polymer and a solvent.
3. The method according to claim 2 , wherein said solvent is selected from the group consisting of water, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, isopropyl alcohol, n-butyl alcohol, methyl isobutyl ketone, tetrahydrofuran, dibutyl ether, ethyl lactate, methyl acetate, ethyl acetate, butyl acetate, 2-heptanone, γ-butyrolactone, and a combination thereof.
4. The method according to claim 2 , a compound, a base, or a base-generating compound.
5. The method according to claim 4 , wherein said acid, said acid-generating compound, said base, or said base-generating compound is selected from the group consisting of primary amine, secondary amine, tertiary amine, quaternary ammonium salt, cyclic amine nitrogen-containing heterocyclic compound, sulfonic acid, carboxylic acid, carboxylic amide, and a salt thereof.
6. The method according to claim 4 , wherein the mass ratios of said polymer, said organic solvent, and said acid, said acid-generating compound, said base, or said base-generating compound to the total mass of the gap filling composition are not less than 2% and not more than 30%, not less than 70% and not more than 98%, and more than 0% and not more than 10%, respectively.
7. The method according to claim 4 , wherein said gap filling composition further comprises a surfactant, a fungicide, an antimicrobial agent, and/or an antifungal agent.
8. The method according to claim 1 , comprising forming, by dry etching and/or wet etching, a mask for etching said layer to be processed.
9. The method according to claim 1 , wherein said step (A4) is carried out by heating at not less than 100° C. and not more than 500° C. for not less than 30 seconds and not more than 300 seconds.
10. The method according to claim 1 , wherein in said step (A1) an etching amount in a depth direction of said layer to be processed is not less than 0.05 μm and not more than 6.00 μm.
11. The method according to claim 1 , wherein an aspect ratio of said pattern is not less than 5 and not more than 25.
12. The method according to claim 1 , wherein the polymer is polyethylene glycol.
13. The method according to claim 1 , wherein the polymer is polypropylene glycol.
14. The method according to claim 1 , wherein the polymer is polypropylene carbonate.
15. The method according to claim 1 , wherein the polymer is polyethylene carbonate.
16. A pattern forming method comprising:
(B1) a step of forming a resist film on a surface of a layer to be processed;
(B2) a step of exposing said resist film;
(B3) a step of contacting a composition comprising a polymer selected from the group consisting of polyethylene glycol, polypropylene glycol, polypropylene carbonate, polyethylene carbonate, polyethylene propylene glycol, and combination of two or more of these polymers and having a mass average molecular weight of not less than 1,000 and not more than 500,000 with said resist film; and
(B4) a step of dry-etching said resist film and said layer to be processed,
wherein an etching rate of said resist film under a dry-etching condition in said step (B4) is not more than 0.5 times as large as an etching rate of said layer to be processed.
17. The method according to claim 16 , wherein the composition is a gap filling composition comprising:
the polymer and a solvent.
18. The method according to claim 16 , wherein said resist film is derived from a metal-containing resist composition.
19. The method according to claim 16 , wherein an oxygen-containing gas is used in said step (B4).