电子辐照对AlGaN/GaN HEMT器件电特性的影响  

Effects of Electron Radiation on Al Ga N / Ga N HEMT Electrical Properties

作　　者：谷文萍[1,2] 全思[1] 张林[1] 徐小波[1] 刘盼芝[1] 杨丽媛[1] 

机构地区：[1]长安大学电子与控制工程学院,西安710064 [2]西安电子科技大学微电子学院,西安710071

出　　处：《半导体技术》2015年第4期278-283,共6页Semiconductor Technology

基　　金：国家自然科学基金资助项目(41101357);陕西省自然科学基金资助项目(2013JQ7028;2014JQ8344);西安市科技计划项目(CXY1441(9));博士后基金资助项目(2013M540732);中央高校基本科研业务费专项资金(CHD2012JC095)

摘　　要：采用能量为1 Me V的电子对几种不同结构的Al Ga N/Ga N HEMT器件进行了最高注量为8.575×1014cm-2的辐照。实验发现:电子辐照后,最高注量下器件欧姆接触性能也几乎没有退化。辐照后未钝化器件的正反向栅电流有所增加,而且肖特基势垒高度随着辐照注量的增加而降低。几种结构HEMT器件的辐照结果表明,电子辐照后只有未钝化器件的特性有所退化,随着辐照注量增加,器件漏电流和跨导下降越明显,而且线性区退化大于饱和区,而阈值电压变化很小。分析表明,HEMT器件参数性能退化的主要原因是栅源和栅漏间隔区辐照感生表面态负电荷的产生。此外实验结果也说明Si N钝化、MOS结构和场板结构都是很好的抗辐照加固的手段。Al Ga N / Ga N HEMTs with different structures were irradiated with 1 Me V electron to fluences of 8. 575 × 1014cm- 2. The experiment show that after the electron radiation with the highest fluences,the ohmic contact is so relative robustness to electron. But after irradiation,either forward or reverse gate leakage current of the unpassivated HEMTs are increased,and the schottky barrier height decreases with the increase of the irradiation fluences. The irradiation results of several devices structures show that only unpassivated devices degrade after electron radiation. As the increase of the radiation fluences,both drain current and transconductance of the devices decrease distinctly, and the linear region dagradation more than the saturated region,while the threshold voltage of the devices is relatively unaffected. The analysis results show that the major reason for HEMTs parameters degradation is the creation of electronegative surface state charges in source-gate spacer and gate-drain spacer. These results reveal that the Si N passivation,field plate and MOS structures are effective reinforced approaches.

关 键 词：Al GA N/Ga N HEMT 电子辐照 表面态 辐照加固 辐照损伤 

分 类 号：TN323.4[电子电信—物理电子学]