Drift Mobility and Photoconductivity in Amorphous Silicon

Drift mobility and photoconductivity are studied on amorphous silicon (glow discharge type) by conventional time‐of‐flight technique as well as measurements of the response time. The time‐of‐flight experiments yield dispersive transients which do not allow the definition of a transit time. The drift mobility obtained from steady‐state photoconductivity and response time is thermally activated with an energy of 0.13 to 0.16 eV. No indication for a change in transport mechanism is found in the investigated temperature range (100 K < T < 500 K). Longer exposure to light leads to a decrease of the response time, enhancing the recombination via deep lying centres.