Correlation between the improved stability and low temperature hydrogen effusion in hydrogenated amorphous silicon films grown from hydrogen dilution of silane

Correlation between stability and hydrogen effusion at low temperature has been studied in a series of hydrogenated amorphous silicon (a-Si:H) films grown from different hydrogen (H2) dilution of silane. The hydrogen effusion spectra are decomposed into two components: low and high temperature peaks located near 395 and 500 °C, respectively. The volume fraction of the integrated intensity of the low temperature peak increases with increasing hydrogen dilution. The results indicate that the stability significantly improves when the volume fraction of the low temperature peak is larger than 0.5. For the highly H2-diluted a-Si:H films with the volume fraction more than 0.8, in particular, no or little significant change in the photoconductivity is observed. Possible explanations for the results are discussed.