Epitaxial growth of Ge film on 6H-SiC(0001) by LPCVD

Ge thin films were prepared on 6H-SiC(0001) substrates by low-pressure chemical vapor deposition. X-ray diffraction, Scanning electron Microscope and Raman spectroscopy were applied to characterize the Ge/6H-SiC heterostructures. XRD spectra shows that only one peak is located at 2 theta=26.68 degrees, which indicated that Ge films grow preferentially along < 111 > crystalline orientation on 6H-SiC(0001) Si-face at 850 degrees C. The epitaxial growth of the Ge film follows the Stranski-Krastanow mode, Ge spherical islands form on the two-dimensional layer with a critical thickness of 7.5nm.