HYDROGEN DIFFUSION AND REACTION PROCESSES IN THIN-FILMS INVESTIGATED BY REAL-TIME SPECTROSCOPIC ELLIPSOMETRY

We applied multichannel spectroscopic ellipsometry (SE) to study the k inetics of thin film modification by hydrogen in vacuum and electroche mical environments. In this paper, we focus on the hydrogenation of am orphous silicon films in vacuum by exposure to thermally generated ato mic hydrogen. The method developed to analyze the real time SE data in this particular case is applicable to other processes, and results ar e also included for the coloration Of WO3 by electrochemical incorpora tion of H. Because the ellipsometer can provide spectra in (psi, DELTA ) from 1.5 to 4.5 eV in 16 ms, improved characterization of diffusion and reaction kinetics can result, in comparison with previous work at fixed photon energy.