GALLIUM NITRIDE SEMICONDUCTOR SUBSTRATE AND PROCESS FOR PRODUCING THE SAME

Title:

GALLIUM NITRIDE SEMICONDUCTOR SUBSTRATE AND PROCESS FOR PRODUCING THE SAME

Document Type and Number:

WIPO Patent Application WO/2005/041283

Kind Code:

A1

Abstract:

A processing-degenerated layer occurs when nitride semiconductor single crystal wafers are polished. Etching must be performed for removing the processing-degenerated layer. However, since nitride semiconductors are chemically inert, no appropriate etchant is available. Although potassium hydroxide and phosphoric acid have been proposed as an etchant for GaN, their power of corroding the surface of Ga is weak. For removing the processing-degenerated layer, dry etching with the use of halogen plasma can be conducted. Even Ga surface can be pared off by halogen plasma. However, the dry etching would cause a new problem of surface contamination by metal particles. Therefore, wet etching is performed by the use of HF+H₂O₂, H₂SO₄+H₂O₂, HCl+H₂O₂, HNO₃, etc. having no selectivity, being corrosive and having an oxidation-reduction potential of 1.2 V or higher as an etchant.

Inventors:

NAKAYAMA MASAHIRO (JP)
MATSUMOTO NAOKI (JP)

Application Number:

PCT/JP2004/011683

Publication Date:

May 06, 2005

Filing Date:

August 06, 2004

Export Citation:

Click for automatic bibliography generation Help

Assignee:

SUMITOMO ELECTRIC INDUSTRIES (JP)
NAKAYAMA MASAHIRO (JP)
MATSUMOTO NAOKI (JP)

International Classes:

C30B29/38; H01L21/304; H01L21/306; H01L21/3065; H01L33/32; (IPC1-7): H01L21/306; H01L21/3065

Foreign References:

JPH08316187A	1996-11-29
JPH10233382A	1998-09-02
JP2001244240A	2001-09-07
JP2003218085A	2003-07-31
JP2002043270A	2002-02-08

Other References: