Effect of High-k Passivation Layer on High Voltage Properties of GaN Metal-Insulator-Semiconductor Devices

• Published in: IEEE access Vol. 8; pp. 95642 - 95649
• Main Authors: Cai, Yutao, Wang, Yang, Liang, Ye, Zhang, Yuanlei, Liu, Wen, Wen, Huiqing, Mitrovic, Ivona Z., Zhao, Cezhou
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 2020; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: AlGaN/GaN; Aluminum gallium nitride; Aluminum oxide; Al₂O; Bilayers; Breakdown; breakdown voltage; current collapse; Dielectric properties; Dielectrics; dynamic on-resistance; Gallium nitride; Gallium nitrides; High electron mobility transistors; high-k; High-k dielectric materials; Insulators; Logic gates; MIS (semiconductors); MIS-HEMTs; Monolayers; Passivation; Passivity; Plasma enhanced chemical vapor deposition; Semiconductor devices; Si₂N; Stress; Two dimensional analysis; Zirconium dioxide; ZrO
• DOI: 10.1109/ACCESS.2020.2995906
• ISSN: 2169-3536

In this paper, the GaN-based MIS-HEMTs with Si 3 N 4 single-layer passivation, Al 2 O 3 /SiN x bilayer passivation, and ZrO 2 /SiN x bilayer passivation are demonstrated. High-k dielectrics are adopted as the passivation layer on MIS-HEMTs to suppress the shallow traps on the GaN surface. Besides, high permittivity dielectrics passivated MIS-HEMTs also show an improved breakdown voltage characteristic, and that is explained by 2-D simulation analysis. The fabricated devices with high-k dielectrics/SiN x bilayer passivation exhibit higher power properties than the devices with plasma enhanced chemical vapor deposition-SiN x single layer passivation, including smaller current collapse and higher breakdown voltage. The Al 2 O 3 /SiN x passivated MIS-HEMTs exhibit a breakdown voltage of 1092 V, and the dynamic R on is only 1.14 times the static R on after off-state V DS stress of 150 V. On the other hand, the ZrO 2 /SiN x passivated MIS-HEMTs exhibit a higher breakdown voltage of 1207 V, and the dynamic R on is 1.25 times the static R on after off-state V DS stress of 150 V.