Reactions of Group V Metal Hydrides with Surfaces
The interaction of group V metal hydrides with III–V compound semiconductor surfaces is of fundamental interest to understand the detailed growth mechanism(s) involved in Metal Organic Vapor Phase Epitaxy (MOVPE). We have annealed GaAs and InP substrates with one edge in contact in an MOVPE reactor under H2 combined with AsH3, PH3 and mixtures of both. We present results of analysis of these surfaces after annealing, which help to explain the partial stabilization of the less stable substrate under the particular conditions of annealing. The interaction of AsH3 (PH3) with InP (GaAs) degrades the surface, producing a polycrystalline structure of InAs (GaP). We also show the larger surface reactivity of AsH3 compared to PH3, when annealing with a mixture of both. The chemical species generated through hydride cracking, catalysed by the surface, interfere with the stabilization process. We conclude that these species are not group V dimers.
KeywordsGroup Versus Reflection High Energy Electron Diffraction GaAs Surface Metal Organic Vapor Phase Epitaxy Group Versus Element
Unable to display preview. Download preview PDF.