Gallium Nitride Based Metal-Insulator-Semiconductor (MIS) Structures

Gallium nitride (GaN) metal-insulator-semiconductor (MIS) are very attractive because of their advantages such as a small gate leakage current, a large gate forward voltage, and surface passivation effect suppressing the drain current collapse. However, conventional Schottky barrier transistors suffer from the high gate leakage current and in particular the leakage current in the forward direction can cause fast device degradation. Reduction of the gate leakage current can be realized by employing an insulated gate metal-oxide-semiconductor technique. The interest in the experimental studies of metal-semiconductor (MS), metal-insulator-semiconductor (MIS) Schottky diodes rooted in their importance of the insulating layer between metal and semiconductor. The existence of such interfacial layer can have strong influence on the device characteristics such as the barrier height, ideality factor, and as well the interface state density. Due to the technological importance of the metal-insulator-semiconductor (MIS), a full understanding of its electrical properties is of great interest.