DETERMINATION OF THE DENSITY-OF-STATES AT THE FERMI-LEVEL OF HYDROGENATED AMORPHOUS-SILICON IN THIN-FILM-TRANSISTOR STRUCTURE BY SPACE-CHARGE LIMITED CURRENT MEASUREMENT

We studied the space charge limited current effect in hydrogenated amo rphous silicon (a-Si:H) thin-film transistors (TFTs). We demonstrate t hat the drain current is space charge limited when the source-drain vo ltage is large and the gate voltage is small. Using this space charge limited current we determined the density of states in the gap of a-Si :H in a-Si:H TFT.