Silica for cmp, aqueous dispersion, and process for producing silica for cmp

Patent metadata

Field	Value
Publication number	US-2016177155-A1
Application number	US-201414904565-A
Country	US
Kind code	A1
Filing date	Jul 10, 2014
Priority date	Jul 24, 2013
Publication date	Jun 23, 2016
Grant date	—

Abstract

To reduce scratches during polishing while ensuring an appropriately high polishing rate, provided are a silica for CMP satisfying the following (A) to (C), an aqueous dispersion using a silica for CMP, and a method of producing a silica for CMP: (A) a BET specific surface area of 40 m 2 /g or more and 180 m 2 /g or less; (B) a particle density measured by a He-gas pycnometer method of 2.24 g/cm 3 or more; and (C) a coefficient of variation in primary particle diameter calculated by TEM/image analysis of 0.40 or less.

First claim

1 . A silica for CMP, which satisfies the following (A) to (C):
(A) a BET specific surface area of 40 m 2 /g or more and 180 m 2 /g or less; (B) a particle density measured by a He-gas pycnometer method of 2.24 g/cm 3 or more; and (C) a coefficient of variation in primary particle diameter calculated by TEM/image analysis of 0.40 or less.

2 . A silica for CMP according to claim 1 , wherein the silica for CMP has a fractal shape parameter αmax value within a particle diameter range of from 3 nm to 70 nm of 2.9 or more.

3 . A silica for CMP according to claim 1 , wherein the silica for CMP has a content of Fe of 0.4 ppm or less in terms of Fe 2 O 3 .

4 . A silica for CMP according to claim 1 , wherein the silica for CMP has a content of Al of 0.3 ppm or less in terms of Al 2 O 3 , a content of Ni of 0.1 ppm or less, a content of Cr of 0.1 ppm or less, a content of boron of 1.3 ppm or less, and a content of phosphorus of 0.5 ppm or less.

5 . A silica for CMP, comprising fumed silica produced by a flame hydrolysis reaction of a silane compound.

6 . An aqueous dispersion, comprising a silica for CMP satisfying the following (A) to (C):
(A) a BET specific surface area of 40 m 2 /g or more and 180 m 2 /g or less; (B) a particle density measured by a He-gas pycnometer method of 2.24 g/cm 3 or more; and (C) a coefficient of variation in primary particle diameter calculated by TEM/image analysis of 0.40 or less.

7 . A method of producing a silica for CMP for producing a silica for CMP by subjecting a silane compound to hydrolysis in flame formed in a reaction vessel,
the method comprising producing, under a production condition of an adiabatic flame temperature of 1,800° C. or more and a pressure in the reaction vessel of 10 kPaG or more, a silica for CMP satisfying the following (A) to (C): (A) a BET specific surface area of 40 m 2 /g or more and 180 m 2 /g or less; (B) a particle density measured by a He-gas pycnometer method of 2.24 g/cm 3 or more; and (C) a coefficient of variation in primary particle diameter calculated by TEM/image analysis of 0.40 or less.

8 . A method of producing a silica for CMP according to claim 7 ,
wherein the flame is formed by a multi-tube burner, wherein the silane compound is supplied to the flame by being supplied to a center tube of the multi-tube burner, and wherein a gas flow rate in the center tube of the multi-tube burner is from 50 m/sec to 100 m/sec in terms of a standard state.

Assignees

• Tokuyama Corp

Inventors

• Nakamura Masahiro
• Ishimoto Ryuji

Classifications

• H10P52/403

  of conductive or resistive materials · CPC title

• C09K3/1463 Primary

  Aqueous liquid suspensions · CPC title

• C09K3/1409

  Abrasive particles per se (preparation of diamond C01B32/25) · CPC title

• C01B33/183

  by oxidation or hydrolysis in the vapour phase of silicon compounds such as halides, trichlorosilane, monosilane · CPC title

• C09G1/02

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