Protection of InP epi-ready wafers by controlled oxide growth

Epitaxy ready InP surfaces for MBE applications have been prepared by either thermal or photochemical oxidation. The composition and thickness of these oxide layers has been determined by XPS. Oval defect densities in GaInAs epitaxial layers have been correlated with the concentration of residual oxygen at the surface after thermal desorption prior to epitaxy. An optimized thermal pretreatment has been evaluated yielding defect free layers. The presence of carbon as a major source of contamination is discussed.