不同氮离子注入参数对聚四氟乙烯表面电荷积聚消散特性的影响  

Effect of different nitrogen ion implantation parameters on surface charge accumulation and dissipation characteristics of polytetrafluoroethene

作　　者：何友辉 陈洪斌[2] 李飞[2] 宋法伦[2] He Youhui;Chen Hongbin;Li Fei;Song Falun(Graduate School of China Academy of Engineering Physics,Mianyang 621900,China;Institute of Applied Electronics,CAEP,Mianyang 621900,China)

机构地区：[1]中国工程物理研究院研究生院,四川绵阳621900 [2]中国工程物理研究院应用电子学研究所,四川绵阳621900

出　　处：《强激光与粒子束》2022年第12期119-131,共13页High Power Laser and Particle Beams

基　　金：国家自然科学基金项目(51907182)。

摘　　要：为了有效抑制聚四氟乙烯(PTFE)材料表面电荷积聚、进一步提升其沿面耐压性能,采用射频产生氮等离子体对其表面进行等离子体浸没离子注入。注入过程中改变射频功率、脉宽、脉冲幅值等参数实现对PTFE样品表面的不同改性效果。通过测试其注入前后的X射线光电子能谱、表面形貌、表面电阻率、表面电位衰减特性、表面陷阱能级及其密度分布,较为系统地研究了不同注入参数对聚四氟乙烯样品表面成分、表面电荷积聚和消散特性的影响。结果表明:注入过程中,氮离子主要通过自身动能促使聚四氟乙烯材料表面分子结构发生破裂和重组来实现表面改性而并非通过化学反应引入新成分,注入氮离子的动能以及数量是决定表面改性效果的主要因素。随着射频源功率增加,射频源对氮气利用效率得到提升,其处理效果饱和点由100 W射频功率下的20 cm^(3)/min升至400 W射频功率下的30 cm^(3)/min,相应表面电阻率由100 W-10 cm^(3)/min条件下的最大值3.3×10^(16)Ω/mm^(2)降至400 W-30 cm^(3)/min条件下的最小值1×10^(15)Ω/mm^(2),并且表面电荷消散速度由6%增加至68%,同时积聚量最多减少了18.6%。另外,随着外施脉冲电压由3 kV-25μs升至7 kV-75μs,表面电阻率最多下降了89%,表面电荷消散速度由4%增加至58%,积聚量最多减少了23.7%。进一步分析表明,经氮离子注入处理的聚四氟乙烯材料表面陷阱能级变浅,加速了表面电荷脱陷,而降低的表面电阻率也促进了脱陷的表面电荷沿面传导,最终使得表面电荷消散加快。To suppress the surface charge accumulation and improve the surface pressure resistance of polytetrafluoroethene(PTFE),the plasma immersion ion implantation was carried out on the surface of PTFE by radio frequency(RF)generation nitrogen plasma.The modification effect of PTFE sample surface was realized by changing RF power,pulse width and pulse amplitude during injection.X-ray photoelectron spectroscopy,surface morphology,surface resistivity,surface potential attenuation characteristics,surface trap energy level and density distribution were measured before and after injection.The effects of different injection parameters on surface composition,surface charge accumulation and dissipation characteristics of PTFE samples were systematically studied.The results show that nitrogen ions can achieve surface modification mainly through their own kinetic energy,rather than introducing new components through chemical reaction.The kinetic energy and quantity of nitrogen ions are the main factors determining the surface modification effect.With the increase of RF source power,nitrogen utilization efficiency of RF source is improved,the saturation point of treatment effect increases from 20 cm^(3)/min at 100 W RF power to 30 cm^(3)/min at 400 W RF power.The corresponding surface resistivity decreases from the maximum value 3.3×10^(16)Ω=mm^(2) at 100 W-10 cm^(3)/min to the minimum value 1×10^(15)Ω/mm^(2)at 400 W-30 cm^(3)/min,the surface charge dissipation rate increases from 6%to 68%.At the same time,the accumulation decreases by 18.6%at most.In addition,when the applied pulse voltage increases from 3 kV-25μs to 7 kV-75μs,The surface resistivity decreased by up to 89%,the surface charge dissipation rate increases from 4%to 58%,and the accumulation decreases by 23.7%at most.Further analysis shows that the trap energy level becomes shallow,which accelerates the surface charge debonding,and the reduced surface resistivity promotes the surface charge conduction along the surface of the debonding,and finally accelerates th

关 键 词：聚四氟乙烯 氮离子注入 表面电荷 积聚消散 表面电阻率 表面陷阱特性 

分 类 号：TM214[一般工业技术—材料科学与工程]