Metal-semiconductor-field effect transistor (MESFET) with lightly doped drain contact region for higher voltage breakdown

Claim 2

A metal-semiconductor field effect transistor (MESFET), comprising: a semiconductor material having highly doped source, drain and gate areas therein; the three areas having the same conductivity type and the gate area being positioned between the drain and source areas and being less highly doped than the source area; and a doping of the drain area being lower than the doping of the gate area.

Claim 3

A metal-semiconductor field effect transistor according to claim 1 in which the semiconductor material comprises gallium arsenide.

Claim 4

A metal-semiconductor field effect transistor according to claim 1 in which the semiconductor material is a thin layer located on a substrate body, drain, gate, and source contacts are all located on a surface of the thin layer opposite the substrate body, and a step is provided on a surface of the layer between the drain and gate areas, the gate and source areas being located at a lower level of the step.

Claim 5

A metal-semiconductor field effect transistor according to claim 1 wherein the doping is N-doping.

Claim 6

A metal-semiconductor field effect transistor (MESFET), comprising: an insulating layer; a semiconductor layer arranged on the insulating layer; contiguous source, gate, and drain zones formed in the semiconductor layer which are all doped with the same conductivity type; electrodes positioned over each of the source, gate and drain zones; a doping of the source zone being greater than a doping of the gate zone and a doping of the gate zone being higher than a doping of the drain zone, the change of doping from the source to the gate and the gate to the drain zones being provided in a contiguous fashion.

Claim 7

A metal-semiconductor field effect transistor (MESFET), comprising: an insulating layer; a semiconductor layer arranged on the insulating layer; contiguous source, gate, and drain zones formed in the semiconductor layer which are all doped with the same conductivity type; electrodes positioned over each of the source, gate and drain zones; a doping of the source zone being greater than a doping of the gate zone and a doping of the gate zone being higher than a doping of the drain zone, the change of doping from the source to the gate and the gate to the drain zones being provided in a contiguous fashion.