Dense composite material, method for producing the same, and component for semiconductor production equipment

Patent metadata

Field	Value
Publication number	US-9188397-B2
Application number	US-201414190531-A
Country	US
Kind code	B2
Filing date	Feb 26, 2014
Priority date	Mar 15, 2013
Publication date	Nov 17, 2015
Grant date	Nov 17, 2015

Abstract

A dense composite material of the present invention contains 37% to 60% by mass of silicon carbide grains, also contains titanium silicide, titanium silicon carbide, and titanium carbide, each in an amount smaller than the mass percent of the silicon carbide grains, and has an open porosity of 1% or less. Such a dense composite material is, for example, characterized in that it has an average coefficient of linear thermal expansion at 40° C. to 570° C. of 7.2 to 8.2 ppm/K, a thermal conductivity of 75 W/mK or more, and a 4-point bending strength of 200 MPa or more.

First claim

What is claimed is:

1. A dense composite material comprising:
37% to 60% by mass of silicon carbide grains; and
titanium silicide, titanium silicon carbide, and titanium carbide, each in an amount smaller than the mass percent of the silicon carbide grains,
wherein the dense composite material has an open porosity of 1% or less.

2. The dense composite material according to claim 1 , wherein the mass percent of titanium carbide is smaller than each of the mass percent of the titanium silicide and the mass percent of the titanium silicon carbide.

3. The dense composite material according to claim 1 , wherein the mass percent of the titanium silicide is larger than the mass percent of the titanium silicon carbide.

4. The dense composite material according to claim 1 , wherein at least one of the titanium silicide, the titanium silicon carbide, and the titanium carbide is present in spaces between the silicon carbide grains so as to cover surfaces of the silicon carbide grains.

5. The dense composite material according to claim 1 , wherein the titanium carbide is dispersed in the titanium silicide.

6. The dense composite material according to claim 1 , wherein the titanium silicide is TiSi 2 .

7. The dense composite material according to claim 1 , wherein the difference in average coefficient of linear thermal expansion at 40° C. to 570° C. between the dense composite material and alumina is 0.5 ppm/K or less.

8. The dense composite material according to claim 1 , wherein the average coefficient of linear thermal expansion at 40° C. to 570° C. is 7.2 to 8.2 ppm/K.

9. The dense composite material according to claim 1 , wherein the dense composite material has a thermal conductivity of 75 W/mK or more.

10. The dense composite material according to claim 1 , wherein the dense composite material has a 4-point bending strength of 200 MPa or more.

11. The dense composite material according to claim 1 , wherein the number of silicon carbide grains having a major axis of 10 μm or more is 16 or more in an SEM image (backscattered electron image) magnified 1,000 times of a region with a size of 90 μm (length)×120 μm (width) of the dense composite material.

12. A joined body comprising a first member composed of the dense composite material according to claim 1 and a second member composed of alumina, the first member and the second member being joined to each other.

13. The joined body according to claim 12 , wherein the first member and the second member are joined to each other by a metal junction.

14. A component for semiconductor production equipment comprising the joined body according to claim 12 .

15. A method for producing a dense composite material comprising:
(a) a step of forming a powder mixture containing 39% to 51% by mass of silicon carbide particles having an average particle size of 10 to 25 μm and at least one starting material selected so that Ti and Si are contained, in which, regarding Si originating from starting materials other than silicon carbide and Ti, the mass ratio Si/(Si+Ti) is 0.26 to 0.54; and
(b) a step of sintering the powder mixture by hot pressing, in an inert atmosphere, at 1,370° C. to 1,460° C. to obtain the dense composite according to claim 1 .

Assignees

• Ngk Insulators Ltd

Inventors

• Jindo Asumi
• Inoue Katsuhiro
• Katsuda Yuji

Classifications

• H10P72/722 Primary

  Details of electrostatic chucks · CPC title

• C04B37/006

  consisting of metals or metal salts · CPC title

• C04B35/5611

  based on titanium carbides · CPC title

• C04B2235/3843

  Titanium carbides · CPC title

• C04B35/58092

  based on refractory metal silicides · CPC title