In-situ electron spectroscopy studies of interaction between P and GaAs(100) surface

摘要

Abstract: The interaction between P and GaAs(100) surface has been studied by XPS, UPS, HREELS, and LEED. The results show that, at room temperature, P is adsorbed on the GaAs surface to form amorphous P thin film. There is less than one monolayer of P atoms bonded to the Ga atoms of the substrate at the interface. The amorphous P overlayer covered on the top of GaAs results in 0.2 eV lowering of the GaAs surface barrier. The thermal annealing at 100$DGR@C - 300$DGR@C causes most of the amorphous P to desorb, with some randomly distributed P-clusters left on the surface. High temperature annealing makes all the remaining P atoms interact with the substrate to form Ga-P bonds. The exchange reaction between deposited P and the substrate takes place successively to form GaAsP thin film when P is deposited on GaAs substrate at higher temperatures. This film is suggested to be a promising passivating film for GaAs surface. !14