Schottky forward current transport mechanisms in AlGaN/GaN HEMTs over a wide temperature range

作     者：武玫 郑大勇 王媛 陈伟伟 张凯 马晓华 张进成 郝跃 

作者机构：School of MicroelectronicsXidian University Key Laboratory for Wide Band-Gap Semiconductor Materials and DevicesSchool of MicroelectronicsXidian University The Fifth Electronics Research Institute of Ministry of Industry and Information Technology 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2014年第23卷第9期

页      面：409-413页

核心收录：

学科分类：0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 

基　　金：supported by the National Natural Science Foundation of China(Grant No.61334002) the Opening Project of Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory of China(Grant No.ZHD201206) 

主　　题：AlGaN/GaN HEMTs Schottky contacts forward current transport mechanism temperature dependence 

摘      要：The behavior of Schottky contacts in AlGaN/GaN high electron mobility transistors （HEMTs） is investigated by temperature-dependent current-voltage （T-I-V） measurements from 300 K to 473 K. The ideality factor and barrier height determined based on the thermionic emission （TE） theory are found to be strong functions of temperature, while present a great deviation from the theoretical value, which can be expounded by the barrier height inhomogeneities. In order to determine the forward current transport mechanisms, the experimental data are analyzed using numerical fitting method, considering the temperature-dependent series resistance. It is observed that the current flow at room temperature can be attributed to the tunneling mechanism, while thermionic emission current gains a growing proportion with an increase in temperature. Finally, the effective barrier height is derived based on the extracted thermionic emission component, and an evaluation of the density of dislocations is made from the I-V characteristics, giving a value of 1.49 × 10^7 cm^-2.