Hydrogen-Terminated Diamond MOSFETs Using Ultrathin Glassy Ga<sub>2</sub>O<sub>3</sub> Dielectric Formed by Low-Temperature Liquid Metal Printing Method
Kaijian Xing, Patjaree Aukarasereenont, Sergey Rubanov, Ali Zavabeti, Daniel L. Creedon, Wei Li, Brett C. Johnson, C. I. Pakes, Jeffrey C. McCallum, Torben Daeneke, Dongchen Qi
Abstract
The p-type surface conductivity of hydrogen-terminated diamond (H-diamond) provides a viable approach toward diamond-based wide-bandgap metal-oxide-semiconductor field-effect transistors (MOSFETs) for high-power and high-frequency electronics. A facile, low-cost, and low-temperature method to form gate dielectrics on diamond that also preserves the integrity of hydrogen-termination is highly desirable for high-performance diamond surface electronics with process flexibility and high yield. In this work, we demonstrate a p-channel diamond MOSFET with an ultrathin glassy Ga2O3 dielectric layer derived from liquid metal. A liquid metal printing method was employed to transfer an amorphous Ga2O3 layer over the desired active p-channel region of H-diamond at low temperature, allowing the protection and preservation the hydrogen-terminated surface while also forming an efficient gate dielectric. The results of this work suggest that the liquid metal method can provide an efficient, low-cost, and high-yield pathway to form high-quality dielectrics for diamond-based transistors.