Heteroepitaxial Diamond Field-Effect Transistor for High Voltage Applications

The exceptional performance of diamondbased field-effect transistor technology is not restricted to devices that use single crystallinediamond alone. This letter explores the full potential of the heteroepitaxial diamond field-effect transistor (HED-FET). HED-FET devices were fabricated with a long gate-drain length (L
_GD
) configuration using C-H bonded channels, and a high maximum current density of 80 mA/mm and a high I
_ON
/I
_OFF
ratio of 10
⁹
were achieved. Additionally, the HED-FETs showed an average breakdown voltage of ≥500 V and comparatively high breakdown voltage of more than 1 kV. This letter represents a significant step toward the realization of the potential of widely available heteroepitaxial diamond for use in FET applications.