HRTEM and energy filtering TEM study of interfacial reaction between diamond film and silicon

Diamond was deposited on Si(100) substrates by microwave plasma assisted chemical vapor deposition in three steps: carburization, biasing and growth. High-resolution transmission electron microscopy (TEM) in cross-sectional view has been used to observe the evolution of microstructures around the interfacial region between diamond and Si in each processing step. The chemistry near the interface was characterized with elemental mapping using an energy-filtered TEM imaging technique. In the carburization stage, an amorphous SiC interlayer 1.5 nm thick was formed between an amorphous carbon layer and Si. In the following biasing stage, β-SiC can form in epitaxial orientation with Si. In the growth stage, diamond grains aligned in a strongly textured condition developed, while the initially grown diamond had polycrystalline characteristics. Processing conditions for epitaxial diamond deposition on Si substrates are briefly discussed.