Methods and devices related to electrodes for p-type group III nitride compound semiconductors
First Claim
1. A method of forming an electrode of a Group III nitride compound semiconductor having p-type conduction comprising the steps of:
- selecting an element of a first metal electrode layer having an ionization potential that is lower than that of an element of a second metal electrode layer;
selecting said element of said second metal electrode layer so that it has better ohmic contact to said Group III nitride compound semiconductor than said element of said first metal electrode layer;
forming said first metal electrode layer on said Group III nitride compound semiconductor;
forming said second metal electrode layer on said first metal electrode layer; and
carrying out heat treatment so that said element of said second metal electrode layer is distributed more deeply into said Group III nitride compound semiconductor than is said element of said first metal electrode layer.
1 Assignment
0 Petitions
Accused Products
Abstract
An electrode for a Group III nitride compound semiconductor having p-type conduction that has a double layer structure. The first metal electrode layer comprising, for example, nickel (Ni) and the second metal electrode layer comprising, for example, gold (Au). The Ni layer is formed on the Group III nitride compound semiconductor having p-type conduction, and the Au layer is formed on the Ni layer. Heat treatment changes or reverses the distribution of the elements Ni and Au. Namely, Au is distributed deeper into the Group III nitride compound semiconductor than is Ni. As a result, the resistivity of the electrode is lowered and its ohmic characteristics are improved as well as its adhesive strength.
-
Citations
16 Claims
-
1. A method of forming an electrode of a Group III nitride compound semiconductor having p-type conduction comprising the steps of:
-
selecting an element of a first metal electrode layer having an ionization potential that is lower than that of an element of a second metal electrode layer; selecting said element of said second metal electrode layer so that it has better ohmic contact to said Group III nitride compound semiconductor than said element of said first metal electrode layer; forming said first metal electrode layer on said Group III nitride compound semiconductor; forming said second metal electrode layer on said first metal electrode layer; and carrying out heat treatment so that said element of said second metal electrode layer is distributed more deeply into said Group III nitride compound semiconductor than is said element of said first metal electrode layer. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
-
Specification