SEMICLASSICAL MODEL OF ELECTRICALLY DETECTED MAGNETIC-RESONANCE IN UNDOPED A-SI-H

A simple model for spin-dependent photoconductivity is presented based on rate equations for the density of spin pairs in singlet and triple t configuration. The pairs are formed by electrons localized in the co nduction band tail and neutral dangling bonds (e-D degrees). We take i nto consideration thermally induced pair dissociation, spontaneous and microwave-induced spin flips and recombination by non-radiative tunne ling from band tails into dangling bonds, Our model explains, satisfac torily, changes in line shape and the dependence of the signal intensi ty on defect density and microwave power. We conclude that tunneling d ominates recombination even at 300 K, This recombination predominantly involves shallow band tail states.