Polycrystalline p‐type InxGa1−xSb (x=0.20) for optoelectronic devices has been obtained by rapid direct synthesis from high‐purity (99.9999%) In, Ga, and Sb. The uniformity of the composition has been checked by neutron activation analysis and also by x‐ray diffractometry (Vegard‐law approximation). From Hall‐effect measurements an acceptor concentration of 3.2×1017 cm−3 and a mobility of 628 cm2/V s for holes, at liquid nitrogen temperature, have been determined, and from absorption measurements, a quite diffuse edge for the optical absorption coefficient resulted. This paper describes the method of rapid direct synthesis of the ternary compound and the techniques used for the characterization of this material for special optoelectronic applications. © 1996 Society of Photo−Optical Instrumentation Engineers.