Optoelectronic and structural properties of sputter etched surfaces of InP

Abstract
The effects of sputter etching on the optoelectronic and structural properties of 〈100〉 surfaces of InP were investigated by photoluminescence (PL) and Raman scattering in conjunction with capacitance-voltage determinations of the density of surface state Nss. The surfaces were etched in an Ar+ plasma for 5 min with plasma power densities D up to 0.1 W cm−2. The near band edge PL intensity shows a striking dependence on D. Below the threshold for macroscopic structural damage, the behavior of the PL and the Nss are independent of each other. A movement of the Fermi level at the surface is invoked in order to explain the PL response.