IP Library Granted Patent US 7,476,634
Granted Patent B2
US 7,476,634 · App. 11/504,102 · Granted Jan 13, 2009

Yttria sintered body and manufacturing method therefor

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Quick Facts
Patent No.
US 7,476,634
App. No.
11/504,102
Granted
Jan 13, 2009
Kind
B2
Abstract

To provide a yttria sintered body having an excellent corrosion resistance to halogen-based corrosive gases and plasma and an excellent thermal shock resistance, and adapted for use as a component member in manufacturing apparatuses for semiconductor and liquid crystal devices, particularly in a plasma process apparatus. A yttria sintered body including tungsten of an average particle size of 3 μm or less dispersed in the yttria so that a ratio of the tungsten relative to the yttria is ranging from 1 to 50% in terms of weight, and having an open pore rate of 0.2% or less and a thermal shock resistance by water submersion method of 200° C. or larger.

Claims (6)

1. An yttria sintered body comprising yttria, and tungsten dispersed in the yttria in such a manner that a ratio of the tungsten relative to the yttria is ranging from 1 to 50% in terms of weight,

wherein an open pore rate of the yttria sintered body is 0.2% or less and

a thermal shock resistance of the yttria sintered body is 200° C. or more in a water submersion method.

2. The yttria sintered body according to claim 1 , wherein the tungsten has an average particle size of 3 μm or less.

3. An yttria sintered body comprising yttria and tungsten dispersed the yttria in such a manner that a ratio of the tungsten relative to the yttria is ranging from 1 to 50% in terms of weight, wherein an open pore rate of the yttria sintered body is 0.2% or less.

4. The yttria sintered body according to claim 3 , wherein a volume resistivity is 10 6 Ω·cm or more and 10 13 Ω·cm or less at 20 to 400° C.

Assignments (2)
MERGER Recorded Sep 12, 2007
From: TOSHIBA CERAMICS CO., LTD.
To: COVALENT MATERIALS CORPORATION
Reel/Frame 019805/0793 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Nov 6, 2006
From: NAGASAKA, SACHIYUKI; MORITA, KEIJI; WATANABE, KEISUKE
To: TOSHIBA CERAMICS CO., LTD.
Reel/Frame 018508/0645 →