A high temperature vacuum annealing method for forming ohmic contacts to GaN and SiC

Author

Papanicolaou, N.A. ; Edwards, A. ; Rao, M.V. ; Wickenden, A.E. ; Kol, D.D. ; Henry, R.L. ; Anderson, W.T.

Author_Institution

Naval Res. Lab., Washington, DC, USA

fYear

1998

Firstpage

122

Lastpage

127

Abstract

In this work we report on the high temperature annealing of Ti/Al and Cr/Al contacts on n-GaN by a vacuum annealing technique. This method consists of annealing the samples on a resistively heated tungsten strip, in vacuum, with an Ar background ambient of 5×10^-5 Torr. Contact resistivities as low as 2.2×10^-5 Ω-cm² and 4.1×10^-5 Ω-cm² were obtained for Ti/Al and Cr/Al ohmic contact metallizations respectively. Auger profile analysis showed minimal oxidation of the Al surface in the vacuum annealed samples whereas high levels of O were observed in the furnace annealed case. A contact resistivity of 4.3×10^-4 Ω-cm² was achieved for Si/Pt metallization on p-SiC

Keywords

Auger electron spectra; annealing; contact resistance; gallium compounds; high-temperature effects; metallisation; ohmic contacts; silicon compounds; wide band gap semiconductors; Auger profile analysis; Cr-Al; GaN; SiC; Ti-Al; contact resistivity; high temperature vacuum annealing; metallization; ohmic contact; Annealing; Argon; Chromium; Conductivity; Metallization; Ohmic contacts; Strips; Temperature; Tungsten; Vacuum technology;

fLanguage

English

Publisher

ieee

Conference_Titel

High Temperature Electronics Conference, 1998. HITEC. 1998 Fourth International

Conference_Location

Albuquerque, NM

Print_ISBN

0-7803-4540-1

Type

conf

DOI

10.1109/HITEC.1998.676772

Filename

676772