Gate oxide

The gate oxide is the dielectric layer that separates the gate terminal of a MOSFET (metal–oxide–semiconductor field-effect transistor) from the underlying source and drain terminals as well as the conductive channel that connects source and drain when the transistor is turned on.

The insulating silicon dioxide layer is formed through a process of self-limiting oxidation, which is described by the Deal–Grove model.

In NMOS-type devices, the zone beneath the gate oxide is a thin n-type inversion layer on the surface of the p-type semiconductor substrate.

In 1955 Carl Frosch and Lincoln Derrick accidentally grew an oxide layer over silicon at Bell Labs and patented their method.

[3] By 1957 Frosch and Derrick were aware of surface passivation by silicon dioxide and made the first gate oxide for a transistors.