Abstract
Based on the hydrogen-terminated surface channel diamond material, a 1 μm gate length diamond metal—insulator—semiconductor field-effect transistor (MISFET) was fabricated. The gate dielectric A12O3 was formed by naturally oxidated thin Al metal layer, and a less than 2 pA gate leakage current was obtained at gate bias between −4 V and 4 V. The DC characteristic of the diamond MISFET showed a drain-current density of 80 mA/mm at drain voltage of −5 V, and a maximum transconductance of 22 mS/mm at gate—source voltage of −3 V. With the small signal measurement, a current gain cutoff frequency of 2.1 GHz was also obtained.