InAsSb/InPSb hetereojunctions 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 degrees 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. (C) 2008 Elsevier B.V. All rights reserved.