Work

Effect of Dual Al2O3 MIS Gate Structure on DC and RF Characteristics of Enhancement-Mode GaN HEMT

Year: 2025

Type: article

Abstract: A dual Al2O3 MIS gate structure is proposed to enhance the DC and RF performance of enhancement-mode GaN high-electron mobility transistors (HEMTs). As a result, the proposed MOS-HEMT with a dual recessed MIS gate structure offers 84% improvements in cutoff frequency (fT) and 92% improvements in maximum oscillation frequency (fmax) compared to conventional HEMTs (from 7.1 GHz to 13.1 GHz and 17.5 GHz to 33.6 GHz, respectively). As for direct-current characteristics, a remarkable reduction in off-state gate leakage current and a 26% enhancement in the maximum saturation drain current (from 519 mA·mm−1 to 658 A·mm−1) are manifested in HEMTs with new structures. The maximum transconductance (gm) is also raised from 209 mS·mm−1 to 246 mS·mm−1. Correspondingly, almost unchanged gate–source capacitance curves and gate–drain capacitance curves are also discussed to explain the electrical characteristic mechanism. These results indicate the superiority of using a dual Al2O3 MIS gate structure in GaN-based HEMTs to promote the RF and DC performance, providing a reference for further development in a miniwatt antenna amplifier and sub-6G frequencies of operation.

Source: Micromachines

DOI: 10.3390/mi16060687

Authors: Yuan Li, Yong Huang, Jing Li, Huiqing Sun, Zhiyou Guo

Institutions: South China Normal University, Guangdong Polytechnic Normal University, Nanjing Xiaozhuang University

Language: English

Topic: GaN-based semiconductor devices and materials

Subfield: Condensed Matter Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,534

Funders: National Natural Science Foundation of China, Government of Jiangsu Province, Natural Science Foundation of Guangdong Province, Natural Science Foundation of Jiangsu Province