Growth of InAsSb/InPSb heterojunctions for mid-IR detector applications

InAsSb/InPSb heterojunctions and InAsSb homojunctions were grown by metalorganic vapor phase epitaxy (MOVPE) on GaSb for potential mid-infrared photodetector applications. Despite the presence of a large miscibility gap for both InAsSb and InPSb alloys, we have grown excellent structural quality epilayers at a growth temperature of 500 °C using all-alkyl precursors. Hall effect measurements of p-type InAsSb are complicated by the presence of an n-type accumulation layer at the surface. Mesa diode structures were fabricated by wet chemical etching and optical lithography. Heterojunction devices were shown to have higher R 0 A values than homojunction devices at room temperature.