Dielectric thin films for GaN-based high-electron-mobility transistors

作     者：Yan-Rong Li Xing-Zhao Liu Jun Zhu Ji-Hua Zhang Lin-Xuan Qian Wan-Li Zhang 

作者机构：State Key Laboratory of Electronic Thin Films and Integrated Devices School of Microelectronics and Solid-State Electronics University of Electronic Science and Technology of China 

出 版 物：《Rare Metals》 (稀有金属（英文版）)

年 卷 期：2015年第34卷第6期

页      面：371-380页

核心收录：

学科分类：080903[工学-微电子学与固体电子学] 0809[工学-电子科学与技术（可授工学、理学学位）] 07[理学] 070205[理学-凝聚态物理] 08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0702[理学-物理学] 

基　　金：financially supported by the National Nature Science Foundation of China(No.50932002) the Research Foundation for the Doctoral Program of Higher Education of China(No.2012018530003) 

主　　题：GaN-based HEMTs Surface passivation Gate dielectrics Enhancement-mode HEMTs High-permittivity field plate 

摘      要：The effects of dielectric thin films on the performance of GaN-based high-electron-mobility transistors （HEMTs） were reviewed in this work. Firstly, the nonpolar dielectric thin films which act as both the surface passivation layers and the gate insulators of the high-frequency GaN-based high-electron-mobility transistors were presented. Furthermore, the influences of dielectric thin films on the electrical properties of two-dimensional electron gas （2DEG） in the A1GaN/GaN hetero-structures were ana- lyzed. It was found that the additional in-plane biaxial tensile stress was another important factor besides the change in surface potential profile for the device perfor- mance improvement of the A1GaN/GaN HEMTs with dielectric thin films as both passivation layers and gate dielectrics. Then, two kinds of polar gate dielectric thin films, the ferroelectric LiNbO3 and the fluorinated A1203, were compared for the enhancement-mode GaN-based HEMTs, and an innovative process was proposed. At last, high-permittivity dielectric thin films were adopted as passivation layers to modulate the electric field and accordingly increase the breakdown voltage of GaN-based HEMTs. Moreover, the polyimide embedded with Cr particles effectively increased the breakdown voltage of GaNbased HEMTs. Finally, the effects of high-permittivity dielectric thin films on the potential distribution in the drift region were simulated, which showed an expanded electric field peak at the drain-side edge of gate electrode.