碳纳米管场效应晶体管的X射线辐照效应  

X-ray irradiation effects of carbon nanotube field-effect transistors

作　　者：曾天祥 李济芳 郭红霞[2] 马武英[2] 雷志锋[3] 钟向丽 张鸿 王颂文 ZENG Tianxiang;LI Jifang;GUO Hongxia;MA Wuying;LEI Zhifeng;ZHONG Xiangli;ZHANG Hong;WANG Songwen(School of Materials Science and Engineering,Xiangtan University,Xiangtan 411105,China;Northwest Institute of Nuclear Technology,Xi’an 710024,China;Key Laboratory of Reliability Physics and Application Technology for Electronic Components,Fifth Institute of Electronics,Ministry of Industry and Information Technology,Guangzhou 511370,China)

机构地区：[1]湘潭大学材料科学与工程学院,湘潭411105 [2]西北核技术研究所,西安710024 [3]工业和信息化部电子第五研究所,电子元器件可靠性物理及其应用技术重点实验室,广州511370

出　　处：《物理学报》2025年第5期267-274,共8页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:12275230,12027813)资助的课题.

摘　　要：本文针对N型和P型碳纳米管场效应晶体管(carbon nanotube field-effect transistor,CNTFET)开展了10 keV-X射线的总剂量效应研究.结果表明,不同类型的晶体管在辐照后均出现阈值电压漂移、跨导下降、亚阈值摆幅上升和饱和电流下降的现象;辐照过程中,施加浮空偏置的N型器件较开态偏置损伤更严重,而施加开态偏置的P型器件较浮空偏置损伤更严重;N型器件辐照后回滞宽度减小且随着沟道尺寸的增大总剂量损伤愈发严重.辐照过程中产生的陷阱电荷是造成器件参数退化的主要原因;不同类型器件在辐照过程中施加的栅极偏置会影响栅极介质层中陷阱对电子或空穴的捕获,从而使器件呈现不同的辐射损伤特征;辐照后N型器件回滞宽度减小可能是因为辐照产生的带负电陷阱电荷阻碍了水分子、OH基团和栅极介质层中陷阱对电子的捕获;此外,晶体管的沟道尺寸也会影响辐射响应,尺寸越大,辐照过程中栅极介质层中和界面处产生陷阱电荷越多,导致晶体管损伤更为严重.To further understand the patterns and mechanisms of total ionizing dose(TID)radiation damage in carbon nanotube field-effect transistor(CNTFET),the total dose effects of 10 keV X-ray irradiation on N-type and P-type CNTFETs are investigated in this work.The irradiation dose rate is 200 rad(Si)/s,with a cumulative dose of 100 krad(Si)for N-type devices and 90 krad(Si)for P-type devices.The differences in TID effect between N-type and P-type CNTFETs under the conditions of floating gate bias and on-state bias,the influence of irradiation on the hysteresis characteristics of N-type CNTFETs,and the influence of channel sizes on the TID effects of N-type CNTFETs are also explored.The results indicate that both types of transistors,after being irradiated,exhibit the threshold voltage shift,transconductance degradation,increase in subthreshold swing,and decrease in saturation current.In the irradiation process,N-type devices under floating gate bias suffer more severe damage than those under on-state bias,while P-type devices under on-state bias experience more significant damage than those under floating gate bias.The hysteresis widths of N-type devices decrease after being irradiated,and the TID damage becomes more severe with the increase of channel dimensions.The main reason for the degradation of device parameters is the trap charges generated in the irradiated process.The gate bias applied during irradiation affects the capture of electrons or holes by traps in the gate dielectric,resulting in different radiation damage characteristics for different types of devices.The reduction in the hysteresis width of N-type devices after being irradiated may be attributed to the negatively charged trap charges generated during irradiation,which hinders the capture of electrons by water molecules,OH groups,and traps in the gate dielectric.Moreover,the channel dimensions of the transistors also influence their radiation response:larger channel dimensions result in more trap charges generated in the gate dielectric and at the

关 键 词：碳纳米管场效应晶体管 X 射线辐照 总剂量效应 

分 类 号：TN386[电子电信—物理电子学]