The spacistor{{cite book , last = Wolf , first = Oswald , author2=R. T. Kramer , author3=J. Spiech , author4=H. Shleuder , title = Special Purpose Transistors: A Self-Instructional Programmed Manual , publisher =

Prentice Hall Prentice Hall was an American major educational publisher owned by Savvas Learning Company. Prentice Hall publishes print and digital content for the 6–12 and higher-education market, and distributes its technical titles through the Safari B ...

, year = 1966 , pages = 103–117 was a type of

transistor upright=1.4, gate (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (pink). A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch e ...

developed in the 1950s as an improvement over the

point-contact transistor The point-contact transistor was the first type of transistor to be successfully demonstrated. It was developed by research scientists John Bardeen and Walter Brattain at Bell Laboratories in December 1947. They worked in a group led by physicis ...

and the later

alloy junction transistor The germanium alloy-junction transistor, or alloy transistor, was an early type of bipolar junction transistor, developed at General Electric and RCA in 1951 as an improvement over the earlier grown-junction transistor. The usual construction of ...

. It offered much higher speed than earlier transistors. It became obsolete in the early 1960s with the development of the

diffusion transistor A diffused junction transistor is a transistor formed by diffusing dopants into a semiconductor substrate. The diffusion process was developed later than the alloy junction and grown junction processes for making bipolar junction transistors (B ...

. It is composed of a P-N junction with a wide

depletion region In semiconductor physics, the depletion region, also called depletion layer, depletion zone, junction region, space charge region or space charge layer, is an insulating region within a conductive, doped semiconductor material where the mobile ...

, inside which two additional contacts are made: the ''injector'' and the ''modulator''. The P material was called the ''base'' and the N material was called the ''collector''. The ''injector'' acted like a BJT (

bipolar junction transistor A bipolar junction transistor (BJT) is a type of transistor that uses both electrons and electron holes as charge carriers. In contrast, a unipolar transistor, such as a field-effect transistor, uses only one kind of charge carrier. A bipolar ...

) emitter, the ''modulator'' like a base, and the ''collector'' like its BJT namesake. It achieved high speed by reducing the

charge carrier In physics, a charge carrier is a particle or quasiparticle that is free to move, carrying an electric charge, especially the particles that carry electric charges in electrical conductors. Examples are electrons, ions and holes. The term is used ...

's transit time.

References

External links

The Spacistor, A New Class of High-Frequency Semiconductor Devices
March 1957 - prone to oscillation
The Spacistor
July 1961 - operate to 25 Mc (MHz) Transistor types