GROWTH OF (GAAS)1-X(SI2)X METASTABLE ALLOYS USING MIGRATION-ENHANCED EPITAXY

(GaAs)1-x(Si2)x for 0 < x < 0.25 has been successfully grown on GaAs (100) substrates using migration-enhanced epitaxy. Structural and compositional analysis of the as-grown (GaAs)1-x(Si2)x layers indicated single phase epitaxial crystals with zincblende structure in the compositional range 0 < x < 0.25. The lattice constant a0 of the alloys was found to decrease with increasing Si content from 0.56543 nm at x = 0 to 0.5601 nm at x = 0.25. Double-crystal X-ray diffraction rocking curve measurements and cross-sectional transmission electron microscopy studies carried out on a 10 period (GaAs)1-x(Si2)x/GaAs strained layer superlattice indicated sharp and abrupt interfaces of high crystalline quality.