Photoresist polymer and photoresist composition containing the same

• US 7,361,447 B2
• Filed: 06/17/2004
• Issued: 04/22/2008
• Est. Priority Date: 07/30/2003
• Status: Expired due to Fees

• Current Assignee: Hynix Semiconductor Incorporated (SK Hynix Inc.)
• Original Assignee: Hynix Semiconductor Incorporated (SK Hynix Inc.)
• Inventors: Jung, Jae Chang
• Primary Examiner(s): WALKE, AMANDA C
• Application Number:
  US10/870,631
• Publication Number:
  US 20050026080A1
• Time in Patent Office: 1,405 Days
• Field of Search: 430/270.1, 430/273.1, 430/311
• US Class Current: 430/270.1
• CPC Class Codes: C08F 220/1804 C4-(meth)acrylate, e.g. butyl (meth)acrylate, isobutyl (meth)acrylate or tert-butyl (meth)acrylate
• CPC Class Codes: C08F 220/1818 C13or longer chain (meth)acrylate, e.g. stearyl (meth)acrylate
• CPC Class Codes: G03F 7/0045 with organic non-macromolecular light-sensitive compounds not otherwise provided for, e.g. dissolution inhibitors
• CPC Class Codes: G03F 7/0392 the macromolecular compound being present in a chemically amplified positive photoresist composition

Abstract

Photoresist polymers and photoresist compositions containing the same. Photoresist patterns of less than 50 nm are achieved with EUV (Extreme Ultraviolet) as an exposure light source with photoresist compositions comprising (i) a photoresist polymer comprising a polymerization repeating unit of Formula 2 or (ii) a photoresist polymer comprising a polymerization repeating unit of Formula 3 with polyvinylphenol. As a result, excellent etching resistance can be secured although the photoresist patterns have a very small thickness.

wherein R₁, R₂, R₃, R₄, R₅, R₆, R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, a, b, c, d, e, f and g are as defined in the specification.

Claims

1. A photoresist composition comprising:

a photoresist polymer as a base resin;

a photoacid generator; and

an organic solvent;

wherein the base resin comprises a photoresist polymer comprising a polymerization repeating unit of Formula 2;

2. The photoresist composition according to claim 1, wherein the polymerization repeating unit of Formula 2 is poly(9-anthracenemethyl methacrylate/2-hydroxyethyl methacrylate/t-butylacrylate/acrylic acid).

3. The photoresist composition according to claim 1, wherein the acid labile protecting group is selected from the group consisting of t-butyl, tetrahydropyran-2-yl, 2-methyl tetrahydropyran-2-yl, tetrahydrofuran-2-yl, 2-methyl tetrahydrofuran-2-yl, 1-methoxypropyl, 1-methoxy-1-methylethyl, 1-ethoxypropyl, 1-ethoxy-1-methylethyl, 1-methoxyethyl, 1-ethoxyethyl, t-butoxyethyl, 1-isobutoxyethyl and 2-acetylmenth-1-yl.

4. The photoresist composition according to claim 1, wherein the photoacid generator is one or more compounds selected from the group consisting of diphenyl iodide hexafluorophosphate, diphenyl iodide hexafluoroarsenate, diphenyl iodide hexafluoroantimonate, diphenyl p-methoxyphenylsulfonium triflate, diphenyl p-toluenylsulfonium triflate, diphenyl p-isobutylphenylsulfonium triflate, diphenyl p-t-butylphenylsulfonium triflate, triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroarsenate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium triflate, dibutylnaphthylsulfonium triflate, phthalimidotrifluoromethane sulfonate, dinitrobenzyltosylate, n-decyl disulfone, naphthylimido trifluoromethane sulfonate and a compound of Formula 4:

5. The photoresist composition according to claim 1, wherein the photoacid generator is present in an amount ranging from 1 to 8 wt % based on the photoresist polymer.

6. The photoresist composition according to claim 1, wherein the organic solvent is selected from the group consisting of methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propylene glycol methyl ether acetate, cyclohexanone, 2-heptanone, ethyl lactate and mixtures thereof.

7. The photoresist composition according to claim 1, wherein the organic solvent is present in an amount ranging from 500 to 8000 wt % based on the photoresist polymer.

17. A method for forming a photoresist pattern, comprising:

(a) coating the photoresist composition of claim 1 on a top portion of an underlying layer to form a photoresist film;

(b) exposing the photoresist film to EUV light; and

(c) developing the exposed photoresist film to obtain a photoresist pattern.

18. A semiconductor device manufactured according to the method of claim 17.

22. The method according to any one of claim 17 or 19, further comprising performing a soft baking process before part (b) or a post baking process after part (b).

8. A photoresist composition comprising:

a photoresist polymer as a base resin;

a photoacid generator; and

an organic solvent;

wherein the base resin comprises polyvinylphenol and a photoresist polymer comprising a polymerization repeating unit of Formula 3;

9. The photoresist composition according to claim 8, wherein the polyvinylphenol is present in an amount ranging from 5 to 20 wt % based on the photoresist polymer comprising the polymerization repeating unit of Formula 3.

10. The photoresist composition according to claim 8, wherein the composition is used in a resist flow process.

11. The photoresist composition according to claim 8, wherein the polymerization repeating unit of Formula 3 is poly(9-anthracenemethyl methacrylate/t-butylacrylate/acrylic acid).

12. The photoresist composition according to claim 8, wherein the acid labile protecting group is selected from the group consisting of t-butyl, tetrahydropyran-2-yl, 2-methyl tetrahydropyran-2-yl, tetrahydrofuran-2-yl, 2-methyl tetrahydrofuran-2-yl, 1-methoxypropyl, 1-methoxy- 1-methylethyl, 1-ethoxypropyl, 1-ethoxy-1-methylethyl, 1-methoxyethyl, 1-ethoxyethyl, t-butoxyethyl, 1-isobutoxyethyl and 2-acetylmenth- 1-yl.

13. The photoresist composition according to claim 8, wherein the photoacid generator is one or more compounds selected from the group consisting of diphenyl iodide hexafluorophosphate, diphenyl iodide hexafluoroarsenate, diphenyl iodide hexafluoroantimonate, diphenyl p-methoxyphenylsulfonium triflate, diphenyl p-toluenylsulfonium triflate, diphenyl p-isobutylphenylsulfonium triflate, diphenyl p-t-butylphenylsulfonium triflate, triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroarsenate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium triflate, dibutylnaphthylsulfonium triflate, phthalimidotrifluoromethane sulfonate, dinitrobenzyltosylate, n-decyl disulfone, naphthylimido trifluoromethane sulfonate and a compound of Formula 4:

14. The photoresist composition according to claim 8, wherein the photoacid generator is present in an amount ranging from 1 to 8 wt % based on the photoresist polymer.

15. The photoresist composition according to claim 8, wherein the organic solvent is selected from the group consisting of methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propylene glycol methyl ether acetate, cyclohexanone, 2-heptanone, ethyl lactate and mixtures thereof.

16. The photoresist composition according to claim 8, wherein the organic solvent is present in an amount ranging from 500 to 8000 wt % based on the photoresist polymer.

19. A method for forming a photoresist pattern, comprising:

(a) coating the photoresist composition of claim 8 on a top portion of an underlying layer to form a photoresist film;

(b) exposing the photoresist film to EUV light; and

(c) developing the exposed photoresist film to obtain a first photoresist pattern.

20. The method according to claim 19, further comprising performing a resist flow process after part (c) to obtain a second photoresist pattern.

21. A semiconductor device manufactured according to the method of claim 19.