Plasma-assisted oxide removal from p-type GaSb for low resistivity ohmic contacts

Abstract

The effect of several plasma-assisted oxide removal techniques prior to metallization of p-type GaSb was investigated. Compared to conventional chemical methods, the plasma-assisted oxide removal resulted in significant improvement of the specific contact resistivities, obtained from transfer length method measurements. Very low specific contact resistivities of less than 5108 X cm2 were observed after surface pretreatment by H2/Ar sputter etching and low-ion-energy argon irradiation. By eliminating sample exposure to air, in situ Ar irradiation becomes a promising technique for high performance GaSb-based semiconductor diode lasers.