High-quality GaN high-voltage HFETs on silicon

Patent metadata

Field	Value
Publication number	US-9437688-B2
Application number	US-201514834192-A
Country	US
Kind code	B2
Filing date	Aug 24, 2015
Priority date	Dec 9, 2011
Publication date	Sep 6, 2016
Grant date	Sep 6, 2016

Abstract

A GaN HFET includes a silicon substrate with an Al 2 O 3 layer above the silicon substrate. The Al 2 O 3 layer has voids formed therein. A plurality of alternating GaN and AlN layers are above the Al 2 O 3 layer. The GaN and AlN layers are under continuous compressive stress.

First claim

What is claimed is:

1. A GaN HFET, comprising:
a silicon substrate;
an Al 2 O 3 layer above the silicon substrate, the Al 2 O 3 layer having voids formed therein; and
a plurality of alternating GaN and AlN layers above the Al 2 O 3 layer, wherein the GaN and AlN layers are under continuous compressive stress.

2. The GaN HFET of claim 1 , further comprising an amorphous layer located between the silicon substrate and the Al 2 O 3 layer.

3. The GaN HFET of claim 1 , wherein the GaN layers in the plurality of alternating GaN and AlN layers have a minimum thickness of 500 nm.

4. The GaN HFET of claim 1 , wherein the GaN layers in the plurality of alternating GaN and AlN layers have a maximum thickness of 50,000 nm.

5. A method of making a GaN HFET comprising:
forming an amorphous film of AlSiO between a silicon wafer and an Al 2 O 3 film on a surface of the silicon wafer; and
depositing a plurality of alternating GaN and AlN layers above the Al 2 O 3 layer.

6. The method of claim 5 , further comprising forming voids in the Al 2 O 3 film on a top surface of a silicon wafer, wherein the top surface of the silicon wafer is along a <111> silicon crystal orientation, and wherein the voids are filled with AlN and GaN.

7. The method of claim 6 , wherein said forming the voids includes exposing portions of the amorphous film of AlSiO along a bottom of the voids.

Assignees

• Power Integrations Inc

Inventors

• Ramdani Jamal
• Edwards John P
• Liu Linlin

Classifications

• H10P14/6326

  Deposition processes · CPC title

• H10P14/3416

  Nitrides · CPC title

• H10P14/3238

  being insulating materials · CPC title

• H10P14/3216

  Nitrides · CPC title

• H10P14/2905 Primary

  Silicon, silicon germanium or germanium · CPC title