CMP polishing agent, method for manufacturing thereof, and method for polishing substrate

Patent metadata

Field	Value
Publication number	US-10246620-B2
Application number	US-201515303564-A
Country	US
Kind code	B2
Filing date	Mar 26, 2015
Priority date	May 9, 2014
Publication date	Apr 2, 2019
Grant date	Apr 2, 2019

Abstract

The present invention is a CMP polishing agent, including polishing particles, a protective film-forming agent, and water, wherein the protective film-forming agent is a copolymer of styrene and acrylonitrile, and an average molecular weight of the copolymer is 500 or more and 20000 or less. This provides a polishing agent which can polish an insulation film with few polishing scratches and has high polishing selectivity of an insulation film to a polishing stop film in a CMP step, a method for manufacturing the polishing agent, and a method for polishing a substrate by using the polishing agent.

First claim

The invention claimed is:

1. A CMP polishing agent, comprising polishing particles, a protective film-forming agent, and water, wherein
the protective film-forming agent is a copolymer of styrene and acrylonitrile,
an average molecular weight of the copolymer of styrene and acrylonitrile is 500 or more and 20000 or less, and
the copolymer of styrene and acrylonitrile is present in an amount of 0.1 part by mass or more and 5 parts by mass or less on the basis of 100 parts by mass of the polishing particles.

2. The CMP polishing agent according to claim 1 , wherein the polishing particles are wet ceria particles.

3. The CMP polishing agent according to claim 2 , wherein the pH is 3 or more and 7 or less.

4. The CMP polishing agent according to claim 3 , wherein the CMP polishing agent is a CMP polishing agent for polishing an insulation film.

5. A method for polishing a substrate, comprising:
moving the substrate and a turn table relatively to polish an insulation film on a polishing stop film formed on the substrate, with the insulation film being pressed against a polishing pad stuck on the turn table for polishing the substrate, while supplying the CMP polishing agent according to claim 4 onto the polishing pad.

6. The method for polishing a substrate according to claim 5 , wherein the polishing stop film is a polysilicon film and the insulation film is a silicon oxide film.

7. A method for manufacturing the CMP polishing agent according to claim 4 , comprising a step of:
mixing: (i) the polishing particles, (ii) the water, and (iii) the copolymer of styrene and acrylonitrile having an average molecular weight of 500 or more and 20000 or less as the protective film-forming agent to manufacture the CMP polishing agent.

8. The CMP polishing agent according to claim 1 , wherein the pH is 3 or more and 7 or less.

9. The CMP polishing agent according to claim 1 , wherein the CMP polishing agent is a CMP polishing agent for polishing an insulation film.

10. A method for polishing a substrate, comprising:
moving the substrate and a turn table relatively to polish an insulation film on a polishing stop film formed on the substrate, with the insulation film being pressed against a polishing pad stuck on the turn table for polishing the substrate, while supplying the CMP polishing agent according to claim 1 onto the polishing pad.

11. The method for polishing a substrate according to claim 10 , wherein the polishing stop film is a polysilicon film and the insulation film is a silicon oxide film.

12. A method for manufacturing the CMP polishing agent according to claim 1 , comprising a step of:
mixing: (i) the polishing particles, (ii) the water, and (iii) the copolymer of styrene and acrylonitrile having an average molecular weight of 500 or more and 20000 or less as the protective film-forming agent to manufacture the CMP polishing agent.

Assignees

• Shinetsu Chemical Co

Inventors

• Takahashi Mitsuhito

Classifications

• H10P95/062

  involving a dielectric removal step · CPC title

• H10P52/402

  of semiconductor materials · CPC title

• H10W10/17

  formed using trench refilling with dielectric materials, e.g. shallow trench isolations · CPC title

• H10W10/014

  using trench refilling with dielectric materials, e.g. shallow trench isolations · CPC title

• C09G1/02

  containing abrasives or grinding agents {(abrasives as such C09K3/14; polishing of semi-conductors H10P52/40)} · CPC title