Method for fabricating semiconductor device and the semiconductor device

Patent metadata

Field	Value
Publication number	US-9230799-B2
Application number	US-201213981048-A
Country	US
Kind code	B2
Filing date	Jan 23, 2012
Priority date	Jan 25, 2011
Publication date	Jan 5, 2016
Grant date	Jan 5, 2016

Abstract

A method for fabricating a semiconductor device including GaN (gallium nitride) that composes a semiconductor layer and includes forming a gate insulating film, in which at least one film selected from the group of a SiO 2 film and an Al 2 O 3 film is formed on a nitride layer containing GaN by using microwave plasma and the formed film is used as at least a part of the gate insulating film.

First claim

The invention claimed is:

1. A method for fabricating a semiconductor device including GaN (gallium nitride) that composes a semiconductor layer, the method comprising:
forming a first nitride layer on a substrate;
forming a second nitride layer on the first nitride layer;
forming a field oxide layer on the second nitride layer;
forming a gate insulating film in which an Al 2 O 3 film is formed to penetrate the field oxide layer, the first nitride layer, and the second nitride layer, the Al 2 O 3 film is subject to radical oxidation, and
then a SiO 2 film is formed by using microwave plasma, the SiO 2 film penetrating the field oxide layer and the second nitride layer only, and the SiO 2 film located between the Al 2 O 3 film and a gate electrode, wherein
the gate electrode is at least partially located in an opening of the SiO 2 film of the gate insulating film, and
in the forming the gate insulating film, the microwave plasma is generated by using microwaves at a frequency of 2.45 GHz by using a radial line slot antenna.

2. The method for fabricating the semiconductor device according to claim 1 , wherein the forming the gate insulating film includes a plasma-enhanced CVD process using microwave plasma.

3. The method for fabricating the semiconductor device according to claim 1 , wherein the forming the gate insulating film includes a plasma-enhanced ALD process using microwave plasma.

4. The method for fabricating the semiconductor device according to claim 1 , wherein the forming the gate insulating film includes forming a film in which the SiO 2 film and the Al 2 O 3 film are stacked.

5. The method for fabricating the semiconductor device according to claim 4 , wherein the forming the gate insulating film includes forming the Al 2 O 3 film by a thermal ALD process and forming the SiO 2 film by a plasma-enhanced CVD process.

6. The method for fabricating the semiconductor device according to claim 1 , wherein the forming the gate insulating film includes forming the SiO 2 film to form the gate insulating film and includes forming the SiO 2 film by both plasma-enhanced CVD and plasma-enhanced ALD processes.

7. The method for fabricating the semiconductor device according to claim 1 , wherein the forming the gate insulating film includes introducing gas containing nitrogen oxides (NOx) for processing.

8. The method for fabricating the semiconductor device according to claim 1 , wherein the plasma-enhanced ALD process includes introducing deposition gas containing BTBAS (bis-tertiaryl-buthyl-amino-silane) onto the nitride layer.

9. The method for fabricating the semiconductor device according to claim 1 , wherein the forming the gate insulating film includes successively performing the plasma-enhanced ALD and plasma-enhanced CVD processes.

10. The method for fabricating the semiconductor device according to claim 1 , wherein the first nitride layer and the second nitride layer have a heterojunction.

11. The method for fabricating the semiconductor device according to claim 10 , wherein the forming the first nitride layer and the second nitride layer includes forming a nitride layer composed of at least one of a GaN layer and an AlGaN (aluminum gallium nitride) layer.

Assignees

• Teramoto Akinobu
• Kambayashi Hiroshi
• Ueda Hirokazu
• Morozumi Yuichiro
• Harada Katsushige
• Hasebe Kazuhide
• Ohmi Tadahiro
• Univ Tohoku
• Fuji Electric Co Ltd
• Tokyo Electron Ltd

Inventors

• Teramoto Akinobu
• Kambayashi Hiroshi
• Ueda Hirokazu
• Morozumi Yuichiro
• Harada Katsushige
• Hasebe Kazuhide
• Ohmi Tadahiro

Classifications

• H10P14/69391

  the material containing aluminium, e.g. Al2O3 · CPC title

• H10P14/69215

  the material being a silicon oxide, e.g. SiO2 · CPC title

• H10P14/6339

  deposition by cyclic CVD, e.g. ALD, ALE or pulsed CVD · CPC title

• H10P14/3416

  Nitrides · CPC title

• H10P14/662

  Laminate layers, e.g. stacks of alternating high-k metal oxides (adhesion layers or buffer layers H10P14/6508, H10P14/6548) · CPC title