Thin film transistor having an annealed gate oxide and method of making

Abstract

A new and improved thin film field effect transistor and method provides such a transistor having increased operating frequencies and higher output currents. The transistor includes a gate electrode having a non-coplanar surface with respect to the substrate and a deposited semiconductor material overlying the gate electrode to form a current conductor channel between a source and drain. The length of the current conduction channel is determined by the thickness of the gate electrode which can be accurately controlled. As a result, short channel lengths are possible without high precision photolithography for high output currents and fast operating speeds. Further, a gate insulator is disposed between the gate and the deposited semiconductor. The gate insulator, which can be a gate oxide, can be annealed prior to the deposition of the deposited semiconductor to provide enhanced field effect mobilities. This further increases the transistor output currents and operating speeds.