Analysis of the Photochemical Reaction on the Surface for Room Temperature Deposition of SiO₂ Thin Films by Photo-CVD using Vacuum Ultraviolet Light

Abstract

We have analyzed the photochemical reaction for the deposition of SiO2 thin films at room temperature in photo-CVD using a vacuum ultraviolet (VUV) excimer lamp with reflection-absorption spectroscopy using a Fourier transform infrared spectrometer (RAS-FTIR). Tetraethoxyorthosilicate (TEOS) was used as a precursor and two types of excimer lamps were used as light sources. The reaction in VUV-CVD is divided into two stages: the reaction in the vapor phase, and the reaction on the surface of the substrate. In this work, we analyzed the latter stage. As a result of analyzing the spectra obtained, it was found that the main reaction for the formation of the SiO2 film was in the latter stage, in which the dissociation of Si–O bonds in Si–O–CH2 in the adsorbed fragments was preceded by the photo-dissociation of C2H5.

SiO2coating of silver nanoparticles by photoinduced chemical vapor deposition

“…The particles coated with additional oxygen have significantly lower CH 3 incorporated into the coating, as well as less intense signals of the contaminants found at 1400, 1200, 1016, and 975 cm −1 . In addition to reducing hydrocarbon impurities, the presence of oxygen also improves the spectra in the region of the Si-O-Si peak by shifting the peak to a higher wavenumber, which is indicative of more structurally ideal SiO 2 [36]. As expected, the introduction of oxygen also increases the presence of OH (∼3400 cm −1 ).…”

Gas-phase production of gold-decorated silica nanoparticles

“…As shown, the particles produced with oxygen exhibit a much more intense peak at the Si-O-Si stretching region, 800 cm −1 , and at the Si-OH stretching region ∼940 cm −1 . Additionally, the presence of oxygen shifts the peak from the Si-O-Si asymmetric stretch, 1000-1200 cm −1 , towards higher wavenumbers, an indication of more structurally ideal silica [24]. As these results indicate, the silica particles are best produced with a sintering temperature from 1200 to 1400 • C and with 1 slm of oxygen.…”

Nitridation in Photon-Assisted Process Using Argon Excimer Lamp

“…Therefore, we measured the infrared absorption to confirm whether nitrogen bonds with the silicon atom in the film by RAS-FTIR, which enables the high sensitive measurement of a thin film. 12) The curve obtained from the film formed at 25 C in Fig. 3 shows two peaks with the center wavenumbers of 810 and 1200 cm À1 .…”