Demonstration of High-Performance Ultra-Wide Bandgap SrSnO$_3$ Top-Gated MOSFETs

TL;DR

This paper demonstrates high-performance top-gated MOSFETs using ultra-wide bandgap SrSnO$_3$, achieving excellent mobility, high on/off ratio, and low contact resistance, highlighting its potential for power electronics.

Contribution

The study introduces the first high-performance SrSnO$_3$ MOSFETs with hybrid MBE growth and ALD dielectrics, showcasing superior electrical characteristics for power applications.

Findings

Field-effect mobility exceeds 65 cm$^2$/V·s

On/off current ratio above 10^8

Contact resistance of 0.66 Ω·mm

Abstract

We report the demonstration of high-performance top-gated metal-oxide-semiconductor field-effect transistors (MOSFETs) based on the ultra-wide bandgap perovskite oxide SrSnO$_3$ (SSO). Using hybrid molecular beam epitaxy-grown SSO channels and ALD-deposited HfO$_2$ gate dielectrics, the devices exhibit field-effect mobility exceeding 65 cm$^2$/V$\cdot$s, an on-state current up to 194 mA/mm, an on/off current ratio above $10^8$, and a contact resistance of 0.66 $\Omega\cdot$mm. The devices also show a near-ideal subthreshold slope of 68 mV/dec and negligible hysteresis, indicating a high-quality dielectric/semiconductor interface. These results establish SrSnO$_3$ as a promising ultra-wide bandgap oxide semiconductor platform for high-performance power electronic applications.