Cmp Polishing Slurry and Method of Polishing Substrate

• US 20080003925A1
• Filed: 07/20/2005
• Published: 01/03/2008
• Est. Priority Date: 07/23/2004
• Status: Active Grant

• Current Assignee: Resonac Corp. (Resonac Holdings Corp.)
• Original Assignee: Hitachi Chemical Company Limited (Resonac Holdings Corp.)
• Inventors: Ootsuki, Yuuto, Koyama, Naoyuki, Fukasawa, Masato, Haga, Kouji, Kurata, Yasushi, Akutsu, Toshiaki
• Granted Patent: US 9,293,344 B2
• Time in Patent Office: Days
• US Class Current: 451/37
• CPC Class Codes: C09G 1/02 containing abrasives or grinding agents abrasives as such C09K3/14; polishing of semi-conductors H01L
• CPC Class Codes: C09K 3/1463 Aqueous liquid suspensions
• CPC Class Codes: H01L 21/31053 involving a dielectric removal step

Abstract

The present invention relates to a CMP polishing slurry comprising cerium oxide particles, a dispersant, a water-soluble polymer and water, wherein the water-soluble polymer is a polymer obtained in polymerization of a monomer containing at least one of a carboxylic acid having an unsaturated double bond and the salt thereof by using at least one of a cationic azo compound and the salt thereof as a polymerization initiator. The present invention provides a polishing slurry and a polishing method allowing polishing efficiently uniformly at high speed without scratch and also allowing easy process management in the CMP technology of smoothening an interlayer dielectric film, BPSG film, and insulation film for shallow trench isolation.

Claims

1. A CMP polishing slurry comprising cerium oxide particles, a dispersant, a water-soluble polymer and water, wherein the water-soluble polymer is a polymer obtained in polymerization of a monomer containing at least one of a carboxylic acid having an unsaturated double bond and the salt thereof by using at least one of a cationic azo compound and the salt thereof as a polymerization initiator.

2. The CMP polishing slurry according to claim 1, wherein the blending amount of the water-soluble polymer is 0.01 weight part or more and 5 weight parts or less with respect to 100 weight parts of the CMP polishing slurry.

3. The CMP polishing slurry according to claim 1, wherein the weight-average molecular weight of the water-soluble polymer is 200 or more and 50,000 or less.

4. The CMP polishing slurry according to claim 1, wherein the average particle diameter of the cerium oxide particles is 1 nm or more and 400 nm or less.

5. The CMP polishing slurry according to claim 1, wherein the blending amount of the cerium oxide particles is 0.1 weight part or more and 5 weight parts or less with respect to 100 weight parts of the CMP polishing slurry.

6. The CMP polishing slurry according to claim 1, wherein the pH thereof is 4.5 or higher and 6.0 or lower.

7. A polishing method of substrate comprising:

pressing a substrate having a film to be polished against a polishing cloth of a polishing table; and

polishing the film to be polished by moving the substrate and the polishing table relatively to each other while supplying the CMP polishing slurry according to claim 1 between the film to be polished and the polishing cloth.