Transistors 1950-1965
Early Mass Produced Transistors and Diodes
ATT had the license and patents but founder Alexander Graham Bell establish a license free charter granting to companies who use their patents and licenses to build devices to help the hearing impaired non royalty license. Raytheon was an early maker of transistors because their goal was for hearing aid market.
In the early 1950's solid state devices were made of an element called Germanium which was relatively rare and expensive. In 1954, the world's first transistor radio the Regency TR-1 used Texas Instruments germanium transistors. However engineers of this young company found a way to fabricate transistors from silicon which had properties superior to germanium especially reliability and noise. TI's discovery was years ahead of prediction by experts (see TI's website: THE TI SILICON TRANSISTOR ).TI mass produced these devices and set the way toward the integrated circuit and microchips in computers that made them into an industry giant. Silicon is the most common element found in the earth's crust (sand).
Germanium Point Contact Transistors
(Earliest type, hand fitted, fragile and difficult to manufacture)Western Electric 1689 Point Contact Transistor (1952-1953). Early mass produced transistor in unusual glass beaded mount with molded epoxy housing. For telephone applications only.
Germanium Junction Transistors
(Mid 1950's into the 1960's).
Easier to make, reliable and allow transistors to be used in mass produced electronics.
Raytheon Transistors (One of the earliest maker of mass produce transistors for commercial, industrial and military applications. They produced the CK722 the world's first and most famous electronic hobbyist transistor (were rejects of their prime units).
L to R: 2N138, CK789 (hearing aid unit), CK721 and CK722 (all PNP)
BOTTOM ROW L-R: 2N107 (pinch top version), 2N191 and 2N241. These are made either the alloy junction or rate grown process.
TOP ROW: 2N404, 2N1302, 2N1303, 2N1305 and 2N1308
BOTTOM ROW: 2N315 and 2N347
Philco invented a new process to speed up carrier junction mobility from the conventional alloy junction or rate grown process. This allow transistors to operate into the VHF region and paved to way to high speed computer operations and production of compact radio communication products.
EARLY SILICON TRANSISTORS-
More stable and reliable than germanium transistors, paved the way to integrated circuits and computer chips
Texas Instruments 902 (1954) First mass produced silicon deviceNPN Silicon Grown Transistor
Texas Instruments 2N117 (1957) NPN Silicon Grown Junction Transistor
Based on TI's 904 (1955), was the first commercially available 2N registered silicon transistor TI was the first company to do extensive research and development into silicon based transistors. The silicon transistor made TI into a world leader solid state device manufacturer.
SHOWCASE
The Next Big Step: The First Commercial Integrated Circuits Using transistors
>>>>GO TO HEARING AIDS: HEARING AIDS BEFORE 1960
<<<<GO BACK TO MAIN PAGE FOR EARLY VACUUM TUBES AND TRANSISTORS: HOME PAGE
<<<<GO BACK ONE PAGE Sub Miniature Tubes: SUBMINIATURE TUBES