Surface and gas phase reactions induced in a trichlorosilane–SiHx system for silicon film deposition

The surface and gas phase reactions caused by trichlorosilane and SiHx in ambient hydrogen were studied in order to improve the silicon film deposition process. The concentration of trichlorosilane exhausted from the reactor was measured by a quadrupole mass spectra analyzer. Simultaneously, the byproduct deposition that occurred at the exhaust was measured by a quartz crystal microbalance. Based on the measurements, SiHx is considered to increase the trichlorosilane consumption efficiency and to decrease the SiCl2 production by increasing the silicon formation rate from the surface intermediate species, SiCl2. Additionally, trichlorosilane and hydrogen were considered to be reproduced from SiHx and the hydrogen chloride caused by the silicon film formation. •Chemical reactions by SiHCl3 and SiHx gases were studied.•SiHx behaves as an accelerator of Si film formation from SiHCl3.•SiHx simultaneously behaves as a suppressor of the byproduct deposition.