Measurements of the defect density, photoconductivity, and dark conductivity were used to deduce the electron-capture cross-sections of charged and neutral metastable dangling-bond defects in high-quality undoped hydrogenated amorphous material at room temperature. Measurements which had been obtained during optical degradation studies at 4 different temperatures, were analyzed by using photoconductivity models which corresponded to either 1 or 2 types of discrete-level multivalent defect. It was found that a model which involved 2 types of defect was able to describe accurately both the dark conductivity and photoconductivity behaviors. This yielded an electron-capture cross-section of about 10-16cm2 for neutral centers, of both high- (density not increased by light) and low-lying (density increased by light) defects, of about 2 x 10-16cm2 for positively charged high-level defects and of about 2 x 10-15cm2 for positively charged low-lying defects.

R.H.Bube, L.E.Benatar, K.P.Bube: Journal of Applied Physics, 1996, 79[4], 1926-34