DIAMOND LAYERS ON SILICON - FEASIBILITY OF INTERFACE ASSESSMENT BY INFRARED AND RAMAN SPECTROSCOPIES

Using diamond films which were grown by plasma-assisted chemical vapou r deposition on Si(100) and Si(111) substrates as samples, Fourier-tra nsform infrared and Raman spectroscopies were applied with particular emphasis on the investigation of interface properties such as silicon carbide (SiC) formation and strain distribution. While SiC interlayers can be detected with nanometre sensitivity by infrared spectroscopy i t lacks the high spatial resolution obtainable in a micro-Raman experi ment. It will thus be demonstrated that tile presence of a thin SiC in terfacial layer can also be observed in the Raman spectra even despite the low scattering efficiency of SIG. Furthermore, Raman spectra take n in the conventional plane-view geometry are employed to evaluate the lateral homogeneity of the diamond deposition. Cross-sectional Raman spectra, on the other hand, provide information e.g. on the strain dis tribution across the interface. The combination of infrared results wi th those from conventional plane-view as well as cross-sectional Raman spectra consequently give a detailed insight in tile nature of diamon d/Si interfaces.