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Re: Transistorized



At 14:51 11/4/99 -0500, Chuck Britton wrote:
...
but there aren't MANY integrated circuits that don't have transistors
as their major circuit element!
Maybe they are MOS transistors instead of the original junction
transistors, but they are still transistors!
...
Chuck Britton

Junctions?
----------

Shockley tested a prototype field effect device. But results were small
and disappointing. Before the importance of a small distance (0.002 in)
between thin wire electrodes (0.005in diam) was established, a useful
bipolar device was achieved with a wax coated metal collector point,
surrounded by a liquid emitter electrolyte placed on an n type silicon
surface. Its bandwidth was less than 8 Hz.

Soon however (Dec 47) the electrolyte was ditched, and a polystyrene
holder with a piece of gold foil on its narrow face, neatly divided
with a razor cut, was applied to a germanium base.
This was the jackpot:
x100 gain, and frequency response clear up into the audio band.
This was called a point contact device. Junction devices came later,
in 1950.

Brought to you as a courtesy service of Nitpickers Inc.

Ref: Bardeen, Brattain, Letter to The Physical Review, July 1948.

brian whatcott <inet@intellisys.net>
Altus OK