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qfet

acr. (context electronics English) (acronym of lang=en quantum field effect transistor)

Wikipedia
QFET

A quantum field effect transistor (QFET) is a kind of field effect transistor that takes advantage of quantum tunneling to greatly increase the speed of transistor operation by eliminating the traditional transistor's area of electron conduction which typically causes carriers to slow down by a factor of 3000. The result is an increase in logic speed by a factor of 10 with a simultaneous reduction in component power requirement and size also by a factor of 10. It achieves these things through a manufacturing process known as rapid thermal processing (RTP) that uses ultrafine layers of construction materials.

The letters "QFET" also currently exist as a trademarked name of a series of MOSFETs produced by Fairchild Semiconductor which contain a proprietary double-diffused metal–oxide–semiconductor (DMOS) technology but which are not, in fact, quantum-based (the Q in this case standing for "quality").