X-ray-standing-wave interface studies of germanium on Si(111)

Abstract
The position of germanium atoms on a Si(111) (7×7) surface prepared in a molecular-beam-epitaxy system have been established using the characteristic fluorescence generated by x-ray standing waves. For submonolayer coverages germanium occupies both types of (111) lattice sites. Measurements of the germanium position relative to planes inclined to the surface do not support recent stacking-fault models for the Si(111) (7×7) surface.