Polycrystalline diamond RF MOSFET with MoO3 gate dielectric

Abstract

We report the radio frequency characteristics of the diamond metal-oxide-semiconductor field effect transistor with MoO3 gate dielectric for the first time. The device with 2-μm gate length was fabricated on high quality polycrystalline diamond. The maximum drain current of 150 mA/mm at VGS = -5 V and the maximum transconductance of 27 mS/mm were achieved. The extrinsic cutoff frequency of 1.2 GHz and the maximum oscillation frequency of 1.9 GHz have been measured. The moderate frequency characteristics are attributed to the moderate transconductance limited by the series resistance along the channel. We expect that the frequency characteristics of the device can be improved by increasing the magnitude of gm, or fundamentally decreasing the gate-controlled channel resistance and series resistance along the channel, and down-scaling the gate length.

Demonstration of Monolithic Polycrystalline Diamond-GaN Complementary FET Technology for High-Temperature Applications

“…In this work, we focused on the monolithic integration method to fabricate a polycrystalline (PC) diamond hole FET and AlGaN/GaN HEMT simultaneously on a single chip to deliver a complementary inverter for high-temperature. Previous work showing that PC diamond hole FET using a PC diamond plate (Element six TM200) with an average grain size between 80 and 100 μm demonstrates comparable performance to the SC diamond hole FET in recent works, − pointing to the validity of our approach. In a separate study, the role of PC diamond as a heat spreader was also discussed, making this combination even more desirable for various applications .…”