Structural properties of microcrystalline SiC deposited at low substrate temperatures by HWCVD

Microcrystalline silicon carbide (μc-SiC) was prepared at substrate temperatures around 450 °C using hot-wire chemical vapor deposition (HWCVD). The SiC films were deposited from monomethylsilane (MMS) diluted in hydrogen on glass and crystalline silicon substrates. Here, the influence of the MMS-concentration (cMMS) on the microstructure of the films was investigated. X-ray diffraction, transmission electron microscopy, infrared and Raman spectroscopy show a high crystallinity for material prepared at low cMMS. For higher cMMS the crystalline fraction decreases, a silicon-rich amorphous phase evolves, but without extended graphitic inclusions. The highly crystalline films consist of large columnar grains of cubic crystallographic phase with a significant number of stacking faults and a clear preferred growth orientation.