Structural Study of the Si/B(√3×√3)R30° GexSi1-x(111) Interface by Spatially Selective Diffraction Anomalous Fine Structure (DAFS)

Abstract

We have applied a new x-ray structural technique, Diffraction Anomalous Fine Structure (DAFS), to a buried reconstructed interface, Si/B(√3×√3)R30°/GexSi1-x(111) (abbreviated Si/B√3/GexSi1-x(111)). While Ge Kedge XAFS alone gives information about the average local structure surrounding all of the Ge in the sample, by combining the complementary abilities of XAFS and x-ray diffraction, DAFS is able to examine the local structure surrounding just the Ge at the interface, thus exhibiting spatial selectivity. We have made simultaneous XAFS and DAFS measurements of this interface and observed clear differences in the derived χ(k) and resulting Fourier transforms.