Improvement of Hydrogen-Terminated Diamond Field Effect Transistors in Nitrogen Dioxide Atmosphere

The electrical properties of field effect transistors (FETs) fabricated on hydrogen-terminated diamond have been greatly improved by exposing the diamond surface to nitrogen dioxide. Exposure to NO 2 gas significantly increased the hole sheet charge density up to 1.3 × 10 14 cm -2 , which is several times higher than previously reported values. FETs exposed to NO 2 gas exhibited lower source and drain resistances, which facilitated a 1.8 fold increase in maximum drain current, transconductance increased 1.5 times and power gain cut-off frequency increased 1.6 times.