AlGaN/GaN MIS-HEMTs With High Quality ALD-Al2O3 Gate Dielectric Using Water and Remote Oxygen Plasma As Oxidants

• Published in: IEEE journal of the Electron Devices Society Vol. 6; pp. 110 - 115
• Main Authors: Wang, Huan-Chung, Hsieh, Ting-En, Lin, Yueh-Chin, Luc, Quang Ho, Liu, Shih-Chien, Wu, Chia-Hsun, Dee, Chang Fu, Majlis, Burhanuddin Yeop, Chang, Edward Yi
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.01.2018; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: AlGaN/GaN; Aluminum gallium nitrides; Aluminum oxide; Al₂O; Atomic layer epitaxy; Collapse; Current leakage; Dielectrics; Electron mobility; Gallium nitride; Gallium nitrides; Gates; HEMTs; High electron mobility transistors; Insulators; Leakage current; Logic gates; MIS (semiconductors); MIS-HEMT; Oxidizing agents; Oxygen plasma; PEALD; Plasma; Plasma measurements; Plasmas; Semiconductor devices; Silicon; Threshold voltage; Water
• ISSN: 2168-6734
• DOI: 10.1109/JEDS.2017.2779172

We demonstrate the electrical performances of AlGaN/GaN metal-insulator-semiconductor-high electron mobility transistors (MIS-HEMTs) with high quality Al 2 O 3 gate dielectric deposited by plasma enhanced atomic layer deposition using both H 2 O and remote O 2 plasma as oxygen sources. Excellent gate-dielectric/GaN interface and Al 2 O 3 film quality were obtained, resulting in a very small threshold voltage hysteresis and a low interface trap density. The MIS-HEMT device exhibited high on/off current ratio of ~1010, steep subthreshold slope, small gate leakage current, low dynamic on-resistance degradation, and effectively current collapse suppression. These results indicate that incorporating remote O 2 plasma in the ALD-Al 2 O 3 deposition process is an effective and simple way to provide high quality gate dielectric for the GaN MIS-HEMTs production.