Polymer for resist under layer film composition, resist under layer film composition, and patterning process

Patent metadata

Field	Value
Publication number	US-2016284559-A1
Application number	US-201615060934-A
Country	US
Kind code	A1
Filing date	Mar 4, 2016
Priority date	Mar 27, 2015
Publication date	Sep 29, 2016
Grant date	—

Abstract

The invention provides a polymer for a resist under layer film composition, containing a repeating unit shown by the formula (1) and a repeating unit shown by the formula (3),

wherein R 01 independently represents a hydrogen atom or a methyl group; R 02 represents a group selected from the formulae (1-1) to (1-3); R 03 represents a saturated or unsaturated tertiary alkyl group having 4 to 20 carbon atoms and optionally containing an oxygen functional group; and A 2 represents a single bond or a divalent linking group having 2 to 10 carbon atoms and containing an ester group,

wherein the dotted line represents a bonding arm. There can be provided a polymer for a resist under layer film composition that is capable of forming a resist under layer film having good alkali aqueous hydrogen peroxide resistance, excellent filling and planarizing properties, and excellent dry etching property.

First claim

What is claimed is:

1 . A polymer for a resist under layer film composition, comprising a repeating unit shown by the formula (1) and a repeating unit shown by the formula (3),

wherein R 01 independently represents a hydrogen atom or a methyl group; R 02 represents a group selected from the formulae (1-1) to (1-3); R 03 represents a saturated or unsaturated tertiary alkyl group having 4 to 20 carbon atoms and optionally containing an oxygen functional group; and A 2 represents a single bond or a divalent linking group having 2 to 10 carbon atoms and containing an ester group,

wherein the dotted line represents a bonding arm.

2 . The polymer for a resist under layer film composition according to claim 1 , wherein a content of the repeating unit shown by the formula (1) is within a range of 20 mol % to 90 mol % with respect to the whole repeating units, and a content of the repeating unit shown by the formula (3) is within a range of 5 mol % to 50 mol % with respect to the whole repeating units.

3 . The polymer for a resist under layer film composition according to claim 1 , wherein the repeating unit shown by the formula (3) is a repeating unit shown by the formula (3-1),

wherein R 01 and R 03 have the same meanings as above; n represents an integer of 1 to 5.

4 . The polymer for a resist under layer film composition according to claim 1 , further comprising a repeating unit shown by the formula (2),

wherein R 01 has the same meaning as above; A 1 represents a single bond, an ester group, or a divalent linking group having 2 to 10 carbon atoms and containing an ester group; Ar 1 represents a substituted or unsubstituted aryl group having 6 to 20 carbon atoms.

5 . The polymer for a resist under layer film composition according to claim 4 , wherein a content of the repeating unit shown by the formula (2) is within a range of 5 mol % to 50 mol % with respect to the whole repeating units.

6 . The polymer for a resist under layer film composition according to claim 1 , wherein a weight average molecular weight of the polymer is within a range of 1,000 to 20,000.

7 . The polymer for a resist under layer film composition according to claim 1 , wherein a glass transition temperature of the polymer is 50° C. or lower.

8 . The polymer for a resist under layer film composition according to claim 1 , wherein a dispersibility of the polymer is 2.0 or less, the dispersibility being shown by a weight average molecular weight/a number average molecular weight of the polymer.

9 . A resist under layer film composition for use in a multilayer resist method, comprising
(A) a base resin of the polymer for a resist under layer film composition according to claim 1 , and (B) an organic solvent.

10 . The resist under layer film composition according to claim 9 , further comprising one or more of (C) an acid generator, (D) a surfactant, (E) a crosslinking agent, (F) a plasticizer, and (G) a colorant.

11 . The resist under layer film composition according to claim 9 , wherein the resist under layer film composition is capable of forming a resist under layer film that is not peeled when the resist under layer film is formed on a silicon substrate and the silicon substrate is immersed in a 1.0 mass % aqueous hydrogen peroxide containing 0.5 mass % ammonia at 23° C. for 10 minutes.

12 . The resist under layer film composition according to claim 9 , wherein the resist under layer film composition is capable of forming a resist under layer film that is not peeled when the resist under layer film is formed on a silicon substrate and the silicon substrate is immersed in a 1.0 mass % aqueous hydrogen peroxide containing 0.5 mass % ammonia at 65° C. for 5 minutes.

13 . A patterning process for forming a pattern in a substrate to be processed, the process comprising the steps of:
(I-1) forming a resist under layer film on the substrate to be processed by using the resist under layer film composition according to claim 9 ; (I-2) forming a resist upper layer film on the resist under layer film by using a photoresist composition; (I-3) subjecting the resist upper layer film to pattern exposure and development with a developer to form a pattern in the resist upper layer film; and (I-4) transferring the pattern to the resist under layer film by dry etching using the resist upper layer film having the formed pattern as a mask.

14 . A patterning process for forming a pattern in a substrate to be processed, the process comprising the steps of:
(II-1) forming a resist under layer film on the substrate to be processed by using the resist under layer film composition according to claim 9 ; (II-2) forming a resist middle layer film on the resist under layer film; (II-3) forming a resist upper layer film on the resist middle layer film by using a photoresist composition; (II-4) subjecting the resist upper layer film to pattern exposure and development with a developer to form a pattern in the resist upper layer film; (II-5) transferring the pattern to the resist middle layer film by dry etching using the resist upper layer film having the formed pattern as a mask; and (II-6) transferring the pattern to the resist under layer film by dry etching using the resist middle layer film having the transferred pattern as a mask.

15 . A patterning process for forming a pattern in a substrate to be processed, the process comprising the steps of:
(III-1) forming a resist under layer film on the substrate to be processed by using the resist under layer film composition according to claim 9 ; (III-2) forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and silicon oxynitride film on the resist under layer film; (III-3) forming an organic anti-reflective film on the inorganic hard mask intermediate film; (III-4) forming a resist upper layer film on the organic anti-reflective film by using a photoresist composition; (III-5) subjecting the resist upper layer film to pattern exposure and development with a developer to form a pattern in the resist upper layer film; (III-6) transferring the pattern to the organic anti-reflective film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film having the formed pattern as a mask; and (III-7) transferring the pattern to the resist under layer film by dry etching using the inorganic hard mask intermediate film having the transferred pattern as a mask.

16 . The patterning process according to claim 14 , further comprising, after the step (II-6), removing the resist middle layer film having the transferred pattern by wet etching with an alkali aqueous hydrogen peroxide.

17 . The patterning process according to claim 13 , further comprising, after the step (I-4), transferring the pattern to the substrate to be processed by wet etching with an alkali aqueous hydrogen peroxide using the resist under layer film having the transferred pattern as a mask.

18 . The patterning process according to claim 14 , further comprising, after the step (II-6), transferring the pattern to the substrate to be pro

Assignees

• Shinetsu Chemical Co

Inventors

• Kikuchi Rie
• Watanabe Takeru
• Tachibana Seiichiro
• Ogihara Tsutomu

Classifications

• H10P76/2043

  using an anti-reflective coating · CPC title

• H10P76/2041

  Photolithographic processes · CPC title

• H10P76/405

  characterised by their composition, e.g. multilayer masks · CPC title

• H10P50/695

  characterised by the process involved to create the mask, e.g. lift-off masks or sidewalls or to modify the mask · CPC title

• H10P50/692

  characterised by their composition, e.g. multilayer masks or materials · CPC title