Interdiffusion in Ge rich SiGe/Ge multilayers studied by in situ diffraction

Abstract

AbstractWe report on the investigation of diffusion properties of SiGe/Ge multiple quantum well (MQW) structures with period of 24 nm grown strain symmetrized on relaxed SiGe buffers on Si (001) substrates by molecular beam epitaxy. During in situ annealing, X‐ray diffraction experiments were performed on series of MQW structures with average Ge contents of about 70 and 90% using reciprocal space mapping around the (224) reciprocal lattice point. The reciprocal space maps were obtained at elevated temperatures at the ESRF for temperatures from about 600 to 800 °C. The temperatures, where interdiffusion becomes observable, is in the range from 680 to 780 °C for xGe = 0.7 and from 650 to 720 °C for xGe = 0.9. The diffusion parameters were obtained from the analysis of the decay of the periodic satellites in the recorded intensity maps.