Real time i n s i t u 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 (SiH_x , 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.