Reactive ion etching of zinc‐doped InP has been assessed in terms of the degree and extent of the passivation (reduction in carrier concentration). It is found that passivation of acceptors depends on the rf power as well as etching times used. Reduction in carrier concentration as large as three orders of magnitude can be achieved by the use of powers as low as 0.5 W/cm2for 10 min. The effect of this passivation on the characteristics of semiconductor lasers is reported.