Extrinsic gettering of GaAs wafers for MESFETS and integrated circuits

摘要

A method is disclosed for extrinsically gettering imperfections in a semi-insulating GaAs wafer. This is accomplished by subjecting the semi-insulating GaAs wafers to processing conditions which allow the imperfections to migrate toward a mechanically damaged surface region of the wafer. Migration occurs during a low temperature heat treatment over an extended time period. The GaAs wafer surface is damaged by a bead blasting treatment and subsequently heated to a temperature in the range of 400 to 600 degrees Celsius in a forming gas for a period between 12 to 120 hours. Significant improvements of the GaAs wafer qualities and performance of fabricated MESFET devices are achieved.