Abstract
Polycrystalline silicon carbide (SiC) thin films were deposited by plasma enhanced CVD, using hydrogen diluted tetramethylsilane (TMS) as a source gas.
Remarkable peaks were observed in X-ray diffraction patterns of the SiC films prepared from diluted TMS. The XPS measurement showed that samples were stoichiometric composition when they were deposited at 800°C. The optical energy gap was estimated to be about 2.5eV from photo absorption measurements. The resistivity of the film was 10-1-100Ω•cm and the carrier Hall mobility in the film was about 10 cm2/V•s.
Piezoresistive property was measured by canti-lever method. The piezoresistive gauge factor was 7.5. A polycrystalline SiC/single crystal Si heterojunction diode showed well defined rectifying characteristics. The ideally (diode) factor was 1.5. These results show polycrystalline SiC films have promising properties as a material for electronic devices such as heterojunction bipolar transistor or piezoresistive sensor.
