TRANSFER OF EXCESS CHARGE-CARRIERS IN AN A-SI-H CRYSTALLINE-SILICON HETEROJUNCTION MEASURED DURING THE GROWTH OF THE AMORPHOUS-SILICON LAYER/

The plasma-induced deposition of hydrogenated amorphous silicon on cry stalline silicon substrates has been investigated in situ by contactle ss transient photoconductivity measurements. In the initial stage of t he deposition process the signals reflect charge-carrier kinetics in t he substrate with the surface recombination rate modified by the depos ition process. In the final stage the signal is dominated by mobile el ectrons in the film deposited. Between these extrema an additional con tribution of excess charge carriers optically induced in the amorphous silicon film and transported to the substrate is observed. It is show n that this transport is inhibited by a high defect density in the fil m deposited and by a highly defective interface.