XPS study of incident angle effects on the ion beam modification of InP surfaces by 6 keV O-2(+)

The interaction of 6 keV oxygen ions with InP surfaces was studied as a fun ction of O-2(+) ion incident angle. The bombarded InP surfaces were charact erized in situ by x-ray photoelectron spectroscopy (XPS). The XPS measureme nts suggest that surface oxide layers formed by O-2(+) bombardment comprise a mixture of In2O3 and InP oxide. The degree of InP oxidation decreases wi th increasing incident angle. The O-2(+) bombardment also causes depletion of phosphorus from the surface region due to the preferential sputtering of phosphorus from InP. However, the preferential sputtering of phosphorus re duces with increasing incident angle. This decrease of the preferential spu ttering of phosphorus is related to reduced oxidation when increasing the i ncident angle. Copyright (C) 1999 John Wiley & Sons, Ltd.