US 5,180,681 A · Method of making high current, high voltage breakdown field effect transistor

Abstract

The gate voltage breakdown of an integrated circuit field effect transistor, expecially a compound semiconductor metal semiconductor field effect transistor (MESFET) and high electron mobility transistor (HEMT) is dramatically increased by forming an electron trap layer on the surface of the device, under the gate contact and extending beyond the gate contact towards the drain contact. The electron trap layer is preferably a high resistivity lattice matched monocrystalline layer having at least 10.sup.18 traps per cubic centimeter. For gallium arsenide based transistors, the electron trap layer is preferably formed by low temperature molecular beam epitaxy (MBE) of gallium and arsenic fluxes, to produce a monocrystalline gallium arsenide layer having 1% excess arsenic. For indium phosphide based transistors, the electron trap layer is preferably formed by low temperature MBE of aluminum, indium and arsenic fluxes to produce a monocrystalline aluminum indium arsenide layer having 1% excess arsenic.

Claims20

Dependent claims

A method of fabricating an integrated circuit compound semiconductor metal semiconductor field effect transistor (MESFET) comprising the steps of:

providing a compound semiconductor substrate having source and drain regions formed therein at one face thereof and a channel formed between said source and said drain regions;
epitaxially forming an electron trap layer having at least 10.sup.18 electron traps per cubic centimeter on said one face, over at least part of said channel for trapping electrons which flow on said one face and preventing surface current from flowing on said one face;
forming drain and source contacts over said drain and source respectively;
and
forming a gate contact on an interior portion of said electron trap layer, so that said electron trap layer extends beyond said gate contact towards said drain and traps electrons which flow on said one face from said gate contact towards said drain, thereby preventing surface current from flowing on said one face from said gate contact towards said drain;
whereby said MESFET is resistant to voltage breakdown.

3 more elements

Dependencies are inferred from the claim text.

Method of making high current, high voltage breakdown field effect transistor

Life of this patent

Method of making high current, high voltage breakdown field effect transistor

Life of this patent

Abstract

Claims20