CHARACTERIZATION OF AN EPITAXIAL-GROWN DIAMOND THIN-FILM

The epitaxial-grown diamond thin film on a natural diamond (111) substrate from a mixture of hydrogen and acetone by hot-filament-assisted CVD is studied. The deposited thin film is characterized by REM, RHEED, SEM, optical microscopy, the Laue method, Raman spectroscopy and x-ray topography. The deposited film is found to be completely epitaxial to the substrate with good crystallinity and a high degree of surface smoothness in a deposition area of about 4 mm2. No grown defect is observed except regular cleaving grooves formed during growth. REM has been employed for the characterization of the surface fine structure. It is shown that the growth of the (111) thin film occurred by the lateral motion of two sets of straight steps of atomic height consisting of {112} and {110} planes in the surface normal. This lateral epitaxial-grown pattern accounts well for the formation of large-area (111) single-crystal thin film with high quality.