Abstract
Photochemical dissociation of Tetraethoxysilane (TEOS) used as an organic silicon source in the gas phase was investigated by in-situ mass spectrometry. The vacuum uliraviolet (VUV) sources for inducing photochemical reaction were Xe2 excimer lamp (172 nm : 7.2 eV) and Hg lamp (185 nm : 6.5 eV). TEOS was dissociated by irradiation of VUV in the gas phase, while releasing alkyl groups such as CxHy (x= 1-2, y=2-5). Moreover, almost all Si-O bonds of TEOS were not broken at the energy of Xe2 excimer light. It has been found that the species produced by photochemical reaction in the gas phase have long lifetime of at least more than 2 minutes. Finally, the film deposited on the MgF2 window has strong light absorption from visible to ultraviolet region, because the film contains organic compounds.
