Diamond MESFET technology development for microwave integrated circuits

Submicron gate-length metal-semiconductor field effect transistors (MESFETs) were fabricated on hydrogen-terminated-large grain polycrystalline diamond. Devices showed high drain-source current (140 mA/mm) and large transconductance values (50 ms/mm), with a cut off frequency f
_t
=10 GHz and a maximum oscillation frequency, f
_max
, up to 35 GHz. These values suggest device microwave operation in the k-band.