[Formula Omitted]/InAlN/AlN/GaN MIS-HEMTs With 10.8 [Formula Omitted] Johnson Figure of Merit

• Published in: IEEE electron device letters Vol. 35; no. 5; p. 527
• Main Authors: Downey, Brian P, Meyer, David J, Katzer, D Scott, Roussos, Jason A, Pan, Ming, Gao, Xiang
• Format: Journal Article
• Language: English
• Published: New York The Institute of Electrical and Electronics Engineers, Inc. (IEEE) 01.05.2014
• Subjects: Molecular beam epitaxy
• ISSN: 0741-3106; 1558-0563
• DOI: 10.1109/LED.2014.2313023

A high combination of three-terminal breakdown voltage [Formula Omitted] and current gain cutoff frequency [Formula Omitted] was achieved with [Formula Omitted]/InAlN/AlN/GaN metal-insulator-semiconductor high-electron mobility transistors (MIS-HEMTs). A 1-nm [Formula Omitted] gate dielectric was deposited ex situ in a molecular beam epitaxy system and used to increase the carrier density of the 2-D electron gas under an ultrathin InAlN/AlN (2.3 nm/1 nm) barrier. Passivated MIS-HEMTs with a gate length of 80 nm exhibited a drain current density greater than 1.1 A/mm, a peak intrinsic transconductance [Formula Omitted] of 800 mS/mm, and a maximum frequency of oscillation [Formula Omitted] of 230 GHz. The combination of [Formula Omitted] of 114 GHz and [Formula Omitted] of 95 V provides a Johnson figure of merit of 10.8 [Formula Omitted], which is among the highest reported values for fully passivated GaN HEMTs. A peak power-added efficiency of 37.5% with an output power of 1.25 W/mm and an associated gain of 9.7 dB was obtained by load-pull measurements at 40 GHz. [PUBLICATION ABSTRACT]