After World War II the people at
Bell Labs could resume its focus on basic research and development.
The middle chapters of Crystal Fire give many details about this
period through the early 1950s. They learned many things about the
electrical property of different elements, compounds, combinations,
of solid state devices. They
also encountered mysteries about these things that prompted further
research. They also had to spend considerable time obtaining samples
of materials absent undesired impurities or optimal amounts of
desired impurities. Patents
were filed and there were concerns about patents already in place,
what exclusive rights the military might want, and what progress was
being in other labs such as at Purdue University.
There
were two types of transistors invented at Bell Labs during those
years – the point contact invented by John Bardeen and Walter
Brattain and the junction type spearheaded by William Shockley.
In June 1951 Bell
Labs gave a press conference about transistors. The star of the show
was the junction transistor. Perhaps its most remarkable feature was
its extremely low power consumption, about one-millionth of
conventional vacuum tubes. It also amplified signals with far greater
efficiency than the point-contact transistor.
The point-contact
transistor was still used in the Bell System. Practical use of
it came earlier. It entered mass production at Western Electric (a
subsidiary of AT&T), servicing complex switching equipment to
permit direct dialing and bypassing traditional telephone operators.
But the
point-contact transistor never made it to the commercial marketplace
in a big way. Apart from transient usage in hearing aids and military
equipment, the only important applications it ever found came in the
Bell System. Other manufacturers were reluctant to put significant
capital into its production, especially after the recent breakthrough
by Shockley’s team. The future belonged to the junction transistor
and its offspring.
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