PHOTOLUMINESCENCE ENHANCEMENT OF INP TREATED WITH ACTIVATED HYDROGEN

A large enhancement of the photoluminescence intensity emitted by a (100)-oriented InP surface after exposure to activated hydrogen, indicating a sharp reduction of the surface recombination rate, is reported in this work. It is shown, using capacitance-voltage measurements performed on metal-insulator-semiconductor structures, that the hydrogen treatment also results in a strong pinning of the interface Fermi level. These phenomena are interpreted on the following basis: (i) neutralization by hydrogen species of active recombination centers which are deemed to be phosphorus-dangling bonds; an (ii) creation of pinning surface states due to the formation of volatile phosphorus hydride compounds freeing excess indium atoms.