Reversible photoinduced modification of electron-capture cross section at localized states in <i>a</i>-Si:H

Abstract

A reversible photoinduced modification of the electron-capture cross section at localized states in P-doped a-Si:H has been directly observed, being associated with the Staebler–Wronski effect. Isothermal capacitance transient spectroscopy measurement shows that the electron-capture cross section at the gap states located at around 0.5 eV below the conduction-band mobility edge (Ec) increases after the band-gap illumination and is nearly restored to its original value by thermal annealing below 200 °C. It has been suggested that a metastable state related with the dangling bond is created through the multiphonon emission when excess carriers recombine.