Abstract
It has been confirmed that the leakage current observed in Metal-Oxide-Semiconductor (MOS) transistors and polycrystalline thin-film transistors (poly-Si TFTs) corresponds to activation energies of the current. Two new models of the conduction of leakage current have been proposed on the basis of this correspondence. These models consist of two types of steps: the first step is the thermal emission of an electron occurring in the neighborhood of the drain electrode, and the second step is the tunneling of an electron through a trap state in the band gap. These models have enabled us to explain the conduction mechanism of the leakage current in various devices.