Radicals produced by the hot wire-induced decomposition of silane have been
identified using vacuum ultraviolet single photon ionization (SPI). This l
aser-based technique uses 118 nm photons (10.5 eV) to ionize gas phase spec
ies; the resulting photoions are detected using time-of-flight mass spectro
metry. The major silicon-containing gas-phase species identified by SPI dur
ing hot-wire activation of silane gas are Si, SiH3, and Si2H6. These result
s demonstrate that single photon ionization can be a powerful probe for in
situ, real-time detection of multiple species in hot wire chemical vapor de
position. (C) 2001 American Institute of Physics.