Frequency-dependent transport in glow-discharge amorphous silicon

Abstract The frequency-dependent conductivity of glow-discharge a-Si:H has been measured in the temperature range 90–350 K. The bulk and interfacial relaxations are separated by measurement. The interfacial relaxation may originate from a Schottky barrier and is interpreted in terms of a trap-released model. The origin of the bulk a.c. loss is discussed in terms of hydrogen-related two-level systems (TLS) and electron transfer between defect states. The bulk a.c. loss can best be explained by the model for tunnelling of atoms.