Low barrier height gallium arsenide microwave schottky diodes using gold-germanium alloy

Claim 2

A diode according to claim 1 in which said epitaxial layer is approximately 0.5 micrometer thick.

Claim 3

A diode according to claim 1 in which said alloy is in a layer approximately 1,000 Angstrom units thick.

Claim 4

A gallium arsenide Schottky barrier junction comprising a body of ''''n'''' type gallium arsenide with carrier concentration on the order of 1 X 1016 atoms cm 3 and a rectifying metal-semiconductor contact made of an alloy of gold and germanium formed therein while said body is at a temperature below the eutectic for said alloy.

Claim 5

A gallium arsenide Schottky diode having forward conductance starting in the range substantially 0.2 to 0.4 volt comprising a body of n-type gallium arsenide single crystal having ''''n+'''' substrate doped to a level between approximately 7 X 1017 and 1 X 1018 atoms cm 3 and on the substrate an epitaxial ''''n'''' layer with carrier concentration about 7 X 1015 atoms cm 3 approximately 0.5 micrometer thick, a layer of silicon dioxide on said epitaxial layer with a window approximately 7.5 micrometers in diameter therethrough, and a layer approximately 1,000 Angstrom units thick of substantially hyperpure gold-germanium eutectic alloy consisting essentially of 88 weight % gold and 12 weight % germanium overlying said SiO2 layer and in contact with said epitaxial layer through said window.

Claim 6

Method of making a gallium arsenide Schottky diode having forward conductance starting in the range approximately 0.2 to 0.4 volt comprising the steps of providing a body of n-type gallium arsenide single crystal having ''''n+'''' substrate doped to a level on the order of 1 X 1018 atoms cm 3, and on the substrate an epitaxial ''''n'''' layer with carrier concentration on the order of 1 X 1016 atoms cm 3, and depositing a layer of gold-germanium alloy into contact with said epitaxial layer while holding said body at a temperature below the eutectic of said alloy.

Claim 7

The method of claim 7 in which said body is held at a temperature between approximately 200* C. and 300* C.

Claim 8

Method of claim 7 in which during depositing of said alloy, said body is held at a temperature approximately room temperature, and after depositing is completed, said body is raised to a temperature between approximately 200* C. and 300* C. for approximately 1 minute.

Claim 9

The method of claim 9 in which said epitaxial layer is approximately 0.5 micrometer thick.