Path: utzoo!attcan!uunet!wuarchive!udel!berryh
From: berryh@udel.edu (John Berryhill)
Newsgroups: sci.electronics
Subject: Re: Ohmic Contacts to n-AlGaAs
Keywords: ohmic contacts  GaAs, AlGaAs
Message-ID: <8039@nigel.udel.EDU>
Date: 12 Jan 90 15:14:48 GMT
References: <7940@nigel.udel.EDU> <454@sierra.stanford.edu>
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Reply-To: berryh@udel.edu (John Berryhill)
Organization: University of Delaware
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In article <454@sierra.stanford.edu> brooks@sierra.UUCP (Michael B. Brooks) writes:

>E beam evaporate:
>50-100A Ni
>~750A Au/Ge Eutectic
>250A Ni
>1000A Au (for reduced resistivity, the overlayer of Au is essential)

Do you have a reference for this by any chance?

Also, have you tried the recipe by Shih and Blum, "Contact Resistances of
Au-Ge-Ni, Au-Zn and Al to II-V Compounds" from Solid State Electronics,
V15,n11-A, pp. 1177-1180?  Apparently they thermally evaporated an
alloy of the Au-Ge eutectic plus 5%wt. Ni in one shot.  Our E beam
machine is a little flakey and I'd like to stick with thermal evaporation
if I could.  Of course, one of the problems with thermal evaporation
of alloys is that the species will often come out of the boat separately.

--
							      John Berryhill
					   143 King William, Newark DE 19711