🚀 go-pugleaf

Thanks to Chris Parks and others for the info. on GaAs
superconductivity.

I have a totally unrelated question here.. 

People have been working on GaN/AlGaN for some time now. The hope is
that we can have semiconductor light sources in the Blue/Violet/UV some
day, especially since AlGaN is supposed to have a direct band-gap all
the way uptil AlN. 

	The main problem with the material system so far has been the
unintentional doping of more than 1xE18/cc. Also, it is difficult to
grow good quality bulk GaN, or so I heard. The high vapor pressure of 
is the culprit. 

	Besides, the GaN crystal has a hexagonal symmetry, unlike
cubic GaAs, InP, ZnSe, etc. 

	Here's my question - is there a way to find a suitable 
substrate or growing conditions whereby GaN can be grown cubic? If
there are any references, please do send me the information. BTW,
the reason i ask is that i recall someone having said that it was
possible. 

	Also, there might be some solutions to the other two problems,
of which the first, i.e., unintentional doping, is already being 
mitigated. Dr.Kolbas at NCSU has been working on this, and I'm sure
a few others are, too. Are there any better substrates than Sapphire,
which is the most common one? 

	Thanking y'all,
							 swami

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swaminathan srinivasan
center for high tech materials
eece,university of new mexico
albuquerque, nm 87131			swami@chtm.eece.unm.edu
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