Ohmic contact technology in III nitrides using polarization effects of cap layers

被引：29

作者：

Gessmann, T ^{[1
]}

Graff, JW ^{[1
]}

Li, YL ^{[1
]}

Waldron, EL ^{[1
]}

Schubert, EF ^{[1
]}

机构：

[1] Boston Univ, Dept Elect & Comp Engn, Boston, MA 02215 USA

来源：

JOURNAL OF APPLIED PHYSICS | 2002年 / 92卷 / 07期

关键词：

D O I：

10.1063/1.1504169

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

A technology for low-resistance ohmic contacts to III nitrides is presented. The contacts employ polarization-induced electric fields in strained cap layers grown on lattice-mismatched III-nitride buffer layers. With appropriate choice of the cap layer, the electric field in the cap layer reduces the thickness of the tunnel barrier at the metal contact/semiconductor interface. Design rules for polarization-enhanced contacts are presented giving guidance for composition and thickness of the cap layer for different III-nitride buffer layers. Experimental results for ohmic contacts with p-type InGaN and GaN cap layers are markedly different from samples without a polarized cap layer thus confirming the effectiveness of polarization-enhanced ohmic contacts. (C) 2002 American Institute of Physics.

引用

页码：3740 / 3744

页数：5

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