An X-Ray Photoelectron Spectroscopic and Chemical Reactivity Study of Routes to Functionalization of Etched InP Surfaces

Abstract

Although InP is widely used in optoelectronic applications, little is known about the surface chemistry of this important semiconductor. Modification of the InP surface is potentially important as a route to introduce functional groups for the stabilization of InP photoelectrodes,4 to control the surface recombination properties of InP-based electrical devices, to study electron transfer from a solid to a redox-active donor at a fixed distance from the solid, to control nucleation and growth of metals on semiconductors, and for use in optically linked chemical-sensing applications. To our knowledge, the only prior investigations of the derivatization of etched InP surfaces are the work of Gu et al., who coated the InP surface with overlayers of thiols through an unidentified binding mode, and that of Spool et al., who observed face-selective reactivity of InP with benzyl bromides and proposed that the reactivity of the P-rich, (111)B face of InP was dominated by the lone pairs of the terminal P surface atoms. We describe herein a new, apparently general strategy for functionalization of InP surfaces. We also present evidence that the reactions of this semiconductor surface are dominated by the reactivity of residual -OH functionalities on the InP surface.