Crystalline film quality in reduced pressure silicon epitaxy at low temperature

The influence of deposition pressure on epitaxial crystalline film quality has been investigated with respect to vapor-phase silicon epitaxial growth (SiH2Cl2-H2 system). It is shown that the crystalline film quality has been improved by reducing the deposition pressure. In addition, a prebaking process at reduced pressure has been found to be effective for obtaining single-crystalline silicon films with atmospheric pressure deposition as well as reduced pressure deposition. The deposition temperature can be lowered down to 930 °C with perfect crystalline film by reducing the deposition pressure. The crystalline quality of epitaxial films grown at a low temperature of 930 °C using the reduced pressure technique has been verified to be excellent by fabricating bipolar transistors with an oxide isolation technique.