半导体学报（英文版）2013，Vol.34Issue(1)：35-38,4.DOI:10.1088/1674-4926/34/1/014003
Capacitance and conductance dispersion in AlGaN/GaN heterostructure
Capacitance and conductance dispersion in AlGaN/GaN heterostructure
摘要
Abstract
The dispersion mechanism in Alo.27Gao.73N/GaN heterostructure was investigated using frequencydependent capacitance and conductance measurements.It was found that the significant capacitance and conductance dispersion occurred primarily for measurement frequency beyond ～ 100 kHz before the channel cutoff at the interface,suggesting that the vertical polarization electrical field under the gate metal should be closely related with the observed dispersive behavior.According to the Schottky-Read-Hall model,a traditional trapping mechanism cannot be used to explain our result.Instead,a piezoelectric polarization strain relaxation model was adopted to interpret the dispersion.By fitting the obtained capacitance data,the corresponding characteristic time and charge density were determined ～ 10-8 s and ～ 5.26 × 1012 cm-2 respectively,in good agreement with the conductance data and theoretical prediction.关键词
capacitance dispersion/AlGaN/GaN heterostructure/strain relaxation modelKey words
capacitance dispersion/AlGaN/GaN heterostructure/strain relaxation model引用本文复制引用
Yan Dawei,Wang Fuxue,Zhu Zhaomin,Cheng Jianmin,Gu Xiaofeng..Capacitance and conductance dispersion in AlGaN/GaN heterostructure[J].半导体学报（英文版）,2013,34(1):35-38,4.基金项目
Project supported by the Fundamental Research Funds for the Central Universities of China (Nos.JUSRP111A42,JUSRP211A37,JUSRP20914,JUSRP11230),the State Key Laboratory of ASIC & System,China (No.11KF003),and the Natural Science Foundation of Jiangsu Province,China (No.BK2012110). （Nos.JUSRP111A42,JUSRP211A37,JUSRP20914,JUSRP11230）
