Characterization of current injection mechanism in Schottky-barrier metal-oxide-semiconductor field-effect transistors

We discuss the carrier injection mechanism from source/drain to a channel in the on/off-state of Schottky-barrier silicon-on-insulator (SOI) metal-oxide-semiconductor field-effect transistor by developing a refined extraction method for estimation of the Schottky-barrier height. This method is applied to validate the suggested mechanism by utilizing the dummy-gate in an underlap device with a thicker spacer and applying back-gate bias to SOI wafer. The results clearly show that the tunneled carriers from the drain side drive the off-state leakage current. In contrast with the conventional leakage path, the leakage current flows along the interfacial surface of the channel rather than a path underneath the channel.