Bell Labs Point Contact Transistor

Western Electric Point Contact Transistor
Developed by John Bardeen and Walter Brattain at Bell Laboratories, the first transistor was a seminal moment in history. In the main because it was part of the American Telephone and Telegraph Company, Bell Labs was very open in its sharing of the invention, including its methods of manufacture. Being a monopoly, AT&T was very aware of anti-trust pressures. Bell Labs shared its knowledge with 40 licensees in 1951. From demonstrations in 1948, a number of companies had already seen the potential impact of the transistor and had started their own developments. Those with most to lose, the vacuum tube manufacturers, were quickest off the mark including Raytheon, the biggest supplier of mini vacuum tubes.
Point Contact transistors were difficult to manufacture and their reliability was poor. Superior transistor manufacturing methods developed including grown junction and alloy junction. Western Electric at its Allentown PA facility continued to manufacture point contact transistors longer than any other company. Mainly because they had been designed into Bell systems.
I visited the Allentown plant (and Breinigsville) many years later when it was Lucent, still a large facility, but down in size from when 20,000 people worked there. It no longer exists.
Above is a Western Electric Point Contact transistor from the 1950s.
In the background is a page from Walter Brattain's logbook describing the first point contact transistor.

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