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Phil Hobbs wrote in
:

On 2020-05-21 13:33, John Larkin wrote:
On Sun, 17 May 2020 14:15:31 -0000 (UTC), Cursitor Doom
wrote:

Gentlemen,

I have some old OC171 transistors from an old Eddystone short
wave radio I'm restoring. The problem is I suspect they've
developed whiskers, as the resistance readings from e,c and b to
the screen connection are all far too low (sub 10 ohms). A
colleague has suggested blasting the whiskers by tying the ecb
leads together and zapping them against the screen with a 500nF
cap charged to 500VDC. Now this seems a bit counter- intuitive
to me and I'd have thought higher current lower voltage would
be safer for these delicate germanium devices, but WTF do I
know? Is it feasible to remove the whiskers by this sort of
method or any other?

Thanks,

CD

Does anyone still make ge transistors? I can't think of any use
for them.

The only production ge devices I know of (excepting SiGe) are
back diodes, which I think are the only germanium parts
fabricated using lithography.

Ge makes good photodiodes for some uses. They're very leaky, but
if you make the epi thin enough, they can cover 350-1800 nm, which
otherwise requires expensive stacked-die devices. Garden-variety
ones are more like ordinary InGaAs, i.e. 800-1800 nm, which is
much less interesting.

Cheers

Phil Hobbs

https://iopscience.iop.org/article/1.../JJAPS.14S1.57