STRUCTURAL DIFFERENCES BETWEEN HYDROGENATED AND DEUTERATED AMORPHOUS-SILICON FILMS PREPARED BY PLASMA-ENHANCED CHEMICAL VAPOR-DEPOSITION

Hydrogenated and deuterated amorphous silicon films were investigated to determine the origin of the lower photodegradation rates reported for deuterated films. Deuterated layers were deposited onto hydrogenated films and were ineffective in changing the photodegradation rate, implying that hydrogenated and deuterated films exhibit structural differences related to the bulk. Deuterium effused as low as 250-degrees-C, compared with 325-degrees-C for hydrogen, and the deuterium effusion was greater at temperatures below 400-degrees-C. Raman scattering intensities of the TO band were also slightly broader and shifted to higher energy for the deuterated films.