LIQUID-PHASE EPITAXY AND CHARACTERIZATION OF SI1-XGEX LAYERS ON SI SUBSTRATES

Liquid-phase epitaxy allows SiGe alloys of good quality to be grown on Si substrates. We deposit single crystalline, n-type Si1-xGex films with 0.7<x<1 from Bi solutions on (111)-oriented Si. The films are up to several μm thick and are uniform in thickness and in composition. The analysis by x-ray diffraction indicates good crystallinity and a dislocation density below 5×107 cm-2. Photoluminescence measurements show well-resolved peaks with the smallest linewidths reported so far for epitaxial SiGe. Hall-effect measurements yield electron concentrations around 1×1016 cm-3 and room-temperature electron mobilities of up to 340 cm2/V s.