Handle substrates of composite substrates for semiconductors, and composite substrates for semiconductors

Patent metadata

Field	Value
Publication number	US-9673282-B2
Application number	US-201514835960-A
Country	US
Kind code	B2
Filing date	Aug 26, 2015
Priority date	Feb 12, 2014
Publication date	Jun 6, 2017
Grant date	Jun 6, 2017

Abstract

A handle substrate of a composite substrate for a semiconductor is provided. The handle substrate is composed of polycrystalline alumina. The handle substrate includes an outer peripheral edge part with an average grain size of 20 to 55 μm and a central part with an average grain size of 10 to 50 μm. The average grain size of the outer peripheral edge part is 1.1 times or more and 3.0 times or less of that of the central part of the handle substrate.

First claim

The invention claimed is:

1. A composite substrate for a semiconductor: said composite substrate comprising a handle substrate and a donor substrate, said handle substrate comprising polycrystalline alumina;
wherein said handle substrate comprises an outer peripheral edge part and a central part, wherein said outer peripheral edge part has an average grain size of 20 to 55 μm; and
wherein said central part has an average grain size of 10 to 50 μm;
wherein said average grain size of said outer peripheral edge part of said handle substrate is 1.1 times or more and 3.0 times or less of said average grain size of said central part of said handle substrate, and
wherein said handle substrate further comprises a single bonding face comprising a central face part on said central part and an outer peripheral edge face part on said outer peripheral edge part, and
wherein said central face part and said outer peripheral edge face part of said bonding face of said handle substrate are bonded to said donor substrate.

2. The composite substrate of claim 1 , wherein said donor substrate comprises single crystalline silicon.

Assignees

• Ngk Insulators Ltd

Inventors

• Miyazawa Sugio
• Iwasaki Yasunori
• Takagaki Tatsuro
• Ide Akiyoshi
• Nakanishi Hirokazu

Classifications

• H10P90/1914 Primary

  using bonding · CPC title

• C04B2235/786

  Micrometer sized grains, i.e. from 1 to 100 micron · CPC title

• C04B2237/062

  based on silica or silicates · CPC title

• C04B2237/064

  based on alumina or aluminates · CPC title

• C30B33/06

  Joining of crystals · CPC title