Title :
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
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;
Conference_Titel :
High Temperature Electronics Conference, 1998. HITEC. 1998 Fourth International
Conference_Location :
Albuquerque, NM
Print_ISBN :
0-7803-4540-1
DOI :
10.1109/HITEC.1998.676772
