Grown Junction Transistors

Western Electric 2N27 Early Transistor
To the left is a Western Electric grown junction transistor from the mid 1950s, when full rate production started on the first grown junction transistors. The technology was developed in Bell Labs after the point contact transistor, and was significantly more reliable and manufacturable. William Shockley, later to form Shockley Semiconductors on the West Coast, developed the theory of the grown junction transistor.
However they didn't last too long, being pretty much superseded by Alloy Junction transistors. The 2N27, 2N28 and 2N29 were the first grown junction transistors.


GE 2N167 Transistor
General Electric were also an early developer or grown junction transistor technology. The 2N167 germanium grown junction transistor on the left is from the late 1950s. There is a small slab (or bar) of germanium which has been sliced from a larger grown crystal with impurities added to make the npn type transistor structure. The emitter and collector are connected at the ends with the base (in the middle) connected by a small wire bond. Click here to see a larger image https://flic.kr/p/aFRQGc
GE developed transistors at their Electronics Park facilities in Syracuse NY.


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