Appeal No. 96-4052
Application 08/198,511
This is a decision on appeal under 35 U.S.C. § 134 from
the final rejection of claims 31, 33-46, 48, and 49.
We affirm-in-part.
BACKGROUND
The disclosed invention is directed to a method for
photoelectrochemically etching silicon carbide (SiC), and
particularly, to an etching method using selective etching of
different conductivity types of SiC.
Claim 31 is reproduced below.
31. A method for fabricating a semiconductor by
selectively etching, said method comprising the steps of:
providing a substrate;
forming a first semiconducting layer on said
substrate, said first semiconducting layer comprising
p-type silicon carbide, and requiring a first voltage for
charge transport at a surface of said layer in a given
electolytic etching solution;
forming a second semiconductor layer on said first
layer, said second layer comprising n-type silicon
carbide, and requiring a second voltage for charge
transport at a surface of said second layer in said given
electrolytic etching solution which is lower than said
first voltage;
placing said substrate into said given electrolytic
etching solution;
applying a bias voltage to said second semiconductor
layer which is between said first and second voltages;
and
- 2 -
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Next
Last modified: November 3, 2007