Journal of Electronic Materials

, Volume 28, Issue 3, pp 341–346

Effects of annealing in an oxygen ambient on electrical properties of ohmic contacts to p-type GaN

Authors

  • Yasuo Koide
    • Department of Materials Science and EngineeringKyoto University
  • T. Maeda
    • Department of Materials Science and EngineeringKyoto University
  • T. Kawakami
    • Department of Materials Science and EngineeringKyoto University
  • S. Fujita
    • Department of Materials Science and EngineeringKyoto University
  • T. Uemura
    • Technical Department of OptelectronicsToyoda Gosei Co., Ltd.
  • N. Shibata
    • Technical Department of OptelectronicsToyoda Gosei Co., Ltd.
  • Masanori Murakami
    • Department of Materials Science and EngineeringKyoto University
Special Issue Paper

DOI: 10.1007/s11664-999-0037-7

Cite this article as:
Koide, Y., Maeda, T., Kawakami, T. et al. Journal of Elec Materi (1999) 28: 341. doi:10.1007/s11664-999-0037-7

Abstract

Effects of annealing ambient of an oxygen and nitrogen mixed gas on the electrical properties were studied for Au-based ohmic contacts (NiAu, CoAu, CuAu, PdAu, and PtAu) to p-type GaN. Addition of oxygen to the nitrogen gas reduced the specific contact resistances (ρc) and resitivities of the p-GaN epilayers (ρs) of the contacts after annealing at temperatures of 500–600°C. The microstructural analysis at the p-GaN/metal interfaces did not detect the heterostructural intermediate semiconductor layer at the GaN/metal interfaces. The reason for reduction of both the ρc and ρs values by the oxygen gas addition was believed to be due to formation of the p-GaN epilayer with high hole concentrations, caused by removal of hydrogen atoms which bonded with Mg atoms.

Key words

Annealing contact resistance contact ohmic p-GaN

Copyright information

© TMS-The Minerals, Metals and Materials Society 1999