FTIR Studies of H2O and D2O Decomposition on Porous Silicon Surfaces

The decomposition of H2O and D2O on silicon surfaces was studied using transmission Fourier-Transform Infrared FTIR spectroscopy. These FTIR studies were performed in-situ in an ultra-high vacuum chamber using high chamber area porous silicon samples. The FTIR spectra revealed that H2O D02 initially dissociates upon adsorption at 300 K to form SiH SiD and SiOH SiOD surface species. The decomposition of these surface species was then monitored. As the silicon surface was annealed to 650 K, the FTIR spectra revealed that the SiOH surface species progressively decomposed to Si-O-Si species and additional SiH species. Above 650 K, the SiH surface species decreased concurrently with the desorption of H2 from the porous silicon surface. Chemical reactions.