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

Abstract

We studied the space charge limited current effect in hydrogenated amorphous silicon (a-Si:H) thin-film transistors (TFTs). We demonstrate that the drain current is space charge limited when the source-drain voltage 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.