脉冲条件下GaN HEMT电流崩塌效应研究  

A Study on Current Collapse in GaN HEMT's Induced by Pulsed Stress

作　　者：龙飞[1] 杜江锋[1] 罗谦[1] 靳翀[1] 周伟[1] 夏建新[1] 杨谟华[1] 

机构地区：[1]电子科技大学微电子与固体电子学院,四川成都610054

出　　处：《微电子学》2005年第5期478-481,共4页Microelectronics

基　　金：国家自然科学基金资助项目(60072004)

摘　　要：基于GaN HEMT器件实验测试结果,提出了一种GaN电流崩塌效应产生的新观点。大量测试分析发现,脉冲条件下,漏极电流比直流时减小大约50%;脉冲信号频率对电流崩塌效应影响较小;当栅压较小时,随着脉冲宽度的改变,漏脉冲电流按I0(0.89+γT/16)的规律变化。分析认为,电子从栅极注入到栅漏之间,并被表面态捕获,在沟道中形成增加的耗尽层,使得沟道电流减小,从而导致电流崩塌效应。该结论可望用于GaN HEMT器件在脉冲条件下电流崩塌效应进一步的理论探讨和实验研究。Based on the experimental results of GaN HEMT＇s, a new standpoint on current conapse effect of GaN devices is presented. Experimental findings show that drain current is reduced by about 50% in pulsed condition, and compared to pulse width, pulse frequency has less effect on current collapse, and that, as pulse width changes, the drain pulsed current equals to I0 （0.89＋γ/T/16） under small gate stress. The analyses indicate that, since gate iniected electron, which is trapped by surface states between drain and gate, forms an extended depletion layer in the channel, the electron density is reduced and current collapse is generated. The conclusion can be used for further experiments and discussions about current collapse effect of GaN HEMT＇s under pulsed stress.

关 键 词：电流崩塌效应 GAN HEMT 表面态 脉冲测试 

分 类 号：TN304.22[电子电信—物理电子学]