Demonstration of p-GaN/AlGaN/GaN High Electron Mobility Transistors With an Indium-Tin-Oxide Gate Electrode

• Published in: IEEE journal of the Electron Devices Society Vol. 9; pp. 2 - 5
• Main Authors: Chang, Chih-Yao, Wang, Chien-Sheng, Wang, Ching-Yao, Shen, Yao-Luen, Wu, Tian-Li, Kuo, Wei-Hung, Lin, Suh-Fang, Huang, Chih-Fang
• Format: Journal Article
• Language: English
• Published: New York IEEE 2021; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Aluminum gallium nitride; Aluminum gallium nitrides; Electrodes; Gallium nitrides; GaN; HEMTs; high electron mobility transistor (HEMT); High electron mobility transistors; Indium tin oxide; Indium tin oxides; indium–tin–oxide gate electrode; Light emitting diodes; Logic gates; MODFETs; Semiconductor devices; Transistors
• ISSN: 2168-6734; 2168-6734
• DOI: 10.1109/JEDS.2020.3030911

In this study, p-GaN/AlGaN/GaN high electron mobility transistors (HEMTs) with indium-tin-oxide (ITO) gate electrodes are demonstrated. The DC measurements for the devices show a drain current (<inline-formula> <tex-math notation="LaTeX">\text{I}_{\mathrm{ D}} </tex-math></inline-formula>) of 438 mA/mm at a <inline-formula> <tex-math notation="LaTeX">\text{V}_{\mathrm{ D}} </tex-math></inline-formula> and a <inline-formula> <tex-math notation="LaTeX">\text{V}_{\mathrm{ G}} </tex-math></inline-formula> of 10 and 8 V, respectively. A maximum <inline-formula> <tex-math notation="LaTeX">{g} _{\mathrm{ m}} </tex-math></inline-formula> of 92.1 mS/mm and a specific ON-resistance (<inline-formula> <tex-math notation="LaTeX">\text{R}_{\mathrm{ on}}\cdot {\mathrm{ A}} </tex-math></inline-formula>) of 1.86 <inline-formula> <tex-math notation="LaTeX">\text{m}\Omega </tex-math></inline-formula>cm 2 are obtained. Furthermore, the robustness of the ITO gate electrode atop the p-GaN layer under the forward gate bias is studied, indicating stable <inline-formula> <tex-math notation="LaTeX">\text{I}_{\mathrm{ G}}-{\mathrm{ V}}_{\mathrm{ G}} </tex-math></inline-formula> and <inline-formula> <tex-math notation="LaTeX">\text{I}_{\mathrm{ D}}-{\mathrm{ V}}_{\mathrm{ G}} </tex-math></inline-formula> characteristics for a gate voltage of less than 11 V, which is higher than the compared device with Ni/Au Schottky gate contact. Therefore, ITO gate electrodes, which are compatible with the Light-emitting diode (LED) process, are a promising alternative for p-GaN HEMT technologies.