Metal-semiconductor contacts for GaAs bulk effect devices

An alloy of Au, Ge and Ni has been shown to produce uniform linear electrical contacts to GaAs over a resistivity range useful for bulk effect devices. Batch fabrication of devices with contacts of controlled size and shape is readily accomplished by evaporating the contact material through masks onto the semiconductor surface. An eutectic alloy of Au and Ge also produces a linear contact but tends to produce nonuniform films. The preparation of the contact materials, surface treatment of the GaAs, and device fabrication procedures are described. © 1967.