The effects of substrate gettering on GaAs MESFET performance

An increase of about 40 percent in dc transconductance and RF gain of directly ion-implanted GaAs MESFET's was observed when the substrates were subjected to an extrinsic gettering treatment before ion implantation. The gettering treatment consisted of mechanical damage on the backside of the wafer followed by a mild heat treatment. The relationship between material parameters and MESFET performance is discussed and a mechanism for the gettering action is proposed.