Real time <i>i</i> <i>n</i> <i>s</i> <i>i</i> <i>t</i> <i>u</i> observation of the film growth of hydrogenated amorphous silicon by infrared reflection absorption spectroscopy

Abstract

The growth of hydrogenated amorphous silicon films on Al substrates in a flow reactor was studied using infrared reflection absorption spectroscopy. All three hydride species (SiHx , x=1–3) in the growing films were detected as stretching and bending absorption bands in P polarization spectra. The dominant absorption band, initially originating from higher hydrides, was shifted to lower wave numbers with an increase of film thickness. A steep rise in absorption intensity at the initial stage and a time delay in SiH emergence are discussed in terms of the enhancement of detection sensitivity in a hydrogen-rich layer and the time needed for the formation of a bulk-network structure, respectively.