Handle substrates of composite substrates for semiconductors

Patent metadata

Field	Value
Publication number	US-9305827-B2
Application number	US-201414578916-A
Country	US
Kind code	B2
Filing date	Dec 22, 2014
Priority date	Mar 27, 2013
Publication date	Apr 5, 2016
Grant date	Apr 5, 2016

Abstract

A composite substrate for a semiconductor includes a handle substrate 11 and a donor substrate bonded to a surface of the handle substrate 11 directly or through a bonding layer. The handle substrate 11 is composed of an insulating polycrystalline material, a surface 15 of the handle substrate 11 has a microscopic central line average surface roughness Ra of 5 nm or smaller, and recesses 6 are formed on the surface of the handle substrate.

First claim

The invention claimed is:

1. A handle substrate of a composite substrate for a semiconductor;
said handle substrate comprising an insulating polycrystalline material, wherein said handle substrate has a surface having a microscopic central line average surface roughness Ra of 5 nm or smaller; and
wherein recesses are formed on said surface and each recess has an outer profile of a circle or an ellipse in a plan view of said surface of said handle substrate.

2. The handle substrate of claim 1 , wherein a density of said recess having a diameter of 0.5 μm or larger is 50 counts or larger and 4500 counts or smaller per 1 cm 2 of said surface.

3. The handle substrate of claim 1 , wherein an average of a depth of said recess is 0.1 μm or larger and 0.8 μm or smaller.

4. The handle substrate of claim 1 , wherein an average of a diameter of said recess is 1 μm or larger and 5 μm or smaller.

5. The handle substrate of claim 1 , wherein said insulating polycrystalline material comprises alumina, silicon carbide, aluminum nitride or silicon nitride.

6. The handle substrate of claim 5 , wherein said insulating polycrystalline material comprises a translucent alumina ceramics.

7. A composite substrate for a semiconductor, said composite substrate comprising said handle substrate of claim 1 and a donor substrate bonded to said surface of said handle substrate directly or through a bonding layer.

8. The composite substrate for a semiconductor of claim 7 , wherein said bonding layer comprises Al 2 O 3 .

Assignees

• Ngk Insulators Ltd

Inventors

• Ide Akiyoshi
• Iwasaki Yasunori
• Miyazawa Sugio

Classifications

• H10P90/1916

  with separation or delamination along an ion implanted layer, e.g. Smart-cut · CPC title

• H10P90/00

  Preparation of wafers not covered by a single main group of this subclass, e.g. wafer reinforcement · CPC title

• H10P14/2925

  Surface structures · CPC title

• H10P10/128

  by direct semiconductor to semiconductor bonding · CPC title

• H10W10/181

  Semiconductor-on-insulator [SOI] isolation regions, e.g. buried oxide regions of SOI wafers · CPC title