Thin film diamond devices for high temperature electronic applications: hydrogen doped structures

Early predictions that diamond would be a suitable material for high performance, high power that could be operated at high temperatures devices were not supported by the characteristics of diodes and field effect transistors (FETs) fabricated on boron doped (p-type) thin film material. In this paper commercially accessible polycrystalline thin film diamond has been turned p-type by the incorporation of near surface hydrogen. Schottky diodes and metal-semiconductor FETs (MESFETs) have been fabricated using this approach which display unprecedented performance levels; diodes with a rectification ratio >10⁶, leakage currents <1 nA, no indication of reverse bias breakdown at 100 V and an ideality factor of 1.1 have been made. Simple MESFET structures that are capable of withstanding V_DS values of 100 V with low leakage and current pinch-off characteristics have also been fabricated. The operation of these devices at temperatures up to 200°C appears feasible