Thermally Stable Ohmic Contacts for Semiconductor Devices
Original Publication Date: 1988-Dec-01
Included in the Prior Art Database: 2005-Feb-15
A technique is described whereby thermally stable ohmic contacts are prepared, for use in semiconductor devices, by using an indium recoil process. The concept enables a wide selection of ohmic contact metal to be used, such as the same metals for the ohmic contacts and gate. Since the indium doping level is shallow, the technique can be used for shallow channel FET devices. Also, simultaneous doping and barrier height reduction are possible. Thermally stable ohmic contacts with low resistances have been prepared by depositing a small amount of indium within the contact metals for use in a variety of integrated GaAs semiconductor circuits. Ohmic behavior observed in this contact metal is primarily due to the reduction of the barrier height caused by the InxGa1-xAs phases which exist at the metal/GaAs interfaces.