Cadmium doping in vapor phase epitaxial growth of InP has been investigated; a partial pressure of cadmium was produced in an open tube system (In/PC13/H2technique) by heating a cadmium metal source. The characterization of epitaxial layers was carried out over a wide range of doping densities. The distribution coefficient of cadmium was found to be 0.2 for a cadmium partial pressure below 1.5×10−4atm. Above that pressure, a strong compensation limitsNA−NDto a value below 3×1018at. cm−3, while the growth rate decrease from 8 to 3 &mgr;m h−1. The carrier concentration was found to decrease regularly with heat treatment at 300 °C under hydrogen. Photoluminescence measurements have pointed out, in all cases, a broadband emission, centered at 1.3677 eV, corresponding to transition from Cd acceptor levels; however, the near‐edge emission lines, peaked at 1.4105, 1.4115, and 1.4126 eV, in heavily doped layers, vanish upon annealing at 300 °C and are replaced by lines characteristic of lightly doped layers (1.413, 1.4145, 1.417, and 1.4182 eV respectively).