Structural and analytical characterization of Si(1-x)Gex/Si heterosturcures by Rutherford backscattering spectrometry and channeling and double-crystal X-ray-diffractometry

摘要

Thin film Si1-xGex alloys have been grown on silicon by molecular beam epitaxy with nominal composition, x, between 10 and 20 at %. These heterostructures have several applications in band-engineering and in the field of device structures. Film thicknesses, germanium atomic fractions and tetragonal distortion were determined by three different techniques, i.e. Rutherford Backscattering Spectrometry-Channeling, Analytical Electron Microscopy and Double Crystal X-ray Diffractometry. The good agreement found between the various analytical results demonstrates that each technique is capable of a high level of accuracy and consistency. These characterization methods are therefore powerful tools for the precise control of the epitaxial layer growth parameters for the fabbrication of different device structures.