The solid phase hetero-epitaxy of amorphous SiGe on a Si(100) substrate has been investigated, The initial SiGe was deposited bg ion beam sputtering at room temperature from a composite target Of Si and Ge wafers. The solid phase epitaxial SiGe layer was formed through a boron diffusion, thermal annealing and oxidation process, respectively. The boron diffusion was carried out al 970 degrees C and then 1065 degrees C for redistribution, thermal annealing was carried out at 1000 degrees C in a N-2 ambient, and oxidation at 900 degrees C in steam, dry O-2 and steam ambient subsequently. Auger electron spectroscopy, X-ray diffraction, scanning electron microscopy, Rutherford backscattering spectroscopy/channelling, cross-sectional transmission electron microscopy, and Raman Spectroscopy were used to characterize the SiGe sim. The experimental results indicate that through a boron diffusion, Ge atoms diffuse considerably generating a SiGe layer with a lower Ge concentration than that of the as-deposited film, while the thermal annealing makes the amorphous SiGe layer crystallize, for the oxidation of the a-SiGe/Si structure, a newly formed SiGe/Si heterostructure with a higher Ge concentration than that of the as-deposited film has been found due to the selective oxidation of Si at the applied temperature.