Millimeter wave semiconductor device

Claim 1

A gallium arsenide microwave semiconductor device, comprising: (a) a body of N+ doped gallium arsenide semiconductor material with a carrier concentration in the range of about 1×10 18 to 1×10 19 per cubic centimeter, (b) a mesa located on the upper surface of the body and formed of N doped gallium arsenide at a carrier concentration in the range of about 1×10 16 to 5×10 17 per cubic centimeter, (c) a first contacting layer of tantalum in contact with the upper surface of the mesa to form a Schottky barrier diode junction at the interface of the contacting layer and the mesa, said first contacting layer extending along the plane of the upper surface of the mesa beyond the periphery of the Schottky junction, and the surface on the side of the mesa adjacent the Schottky junction being approximately perpendicular to the plane of the upper surface of the mesa, (d) a second contacting layer located substantially in a plane below the plane of the upper surface of said mesa with a thickness of at least one skin depth at the operation frequency in contact with and extending over at least a portion of the upper surface of the body about the base of the mesa, (e) a first electrode connected to and extending over the upper surface of the first contacting layer, (f) a second electrode connected to and extending over the upper surface of the second contacting layer, (g) the exposed edge of said first contacting layer passivated with tantalum oxide, and (h) the surface of the device between the first and second electrode passivated with native oxide.