面向深空探测任务的长寿命碳纳米管阴极研究  

Research on Long Life Carbon Nanotube Cathodes for Deep Space Exploration Missions

作　　者：陈泽宣 肖东阳 杜欢欢 宋培义 CHEN Zexuan;XIAO Dongyang;DU Huanhuan;SONG Peiyi(Precision Gravitational Measurement Facility,School of Physics,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]华中科技大学物理学院引力中心,武汉430074

出　　处：《深空探测学报（中英文）》2024年第2期124-131,共8页Journal Of Deep Space Exploration

基　　金：国家重点研发计划课题(2020YFC2201004);国家自然科学基金重大科研仪器研制项目(11927812)。

摘　　要：针对深空探测对长寿命碳纳米管场发射阴极的应用需求,从CNTs场发射阴极失效的机制分析出发,提出了长寿命CNTs场发射阴极的性能优化方案。采用图形化设计的CNTs发射簇结构可有效降低CNTs发射体表面的场强屏蔽效应,提升阴极的有效发射面积,避免电流集中于部分CNTs从而引起热量累积。提出一种转移键合工艺,将CNTs发射体与衬底的接触由分子力维持转变为金属层熔融键合,提高阴极的机械稳定性并降低了电/热阻抗。在高真空环境下对样机进行性能测试,优化后的CNTs场发射阴极样机实现了0~1 mA的电流范围、<2μA的电流分辨率与1μA/Hz^(1/2)@0.01~1 Hz的噪声水平,并通过了>550 h的连续发射试验,证明了阴极优化后的长周期稳定性。To meet the demand for long-life carbon nanotube field emission cathode in deep space exploration,the failure mechanism of CNTs cathode was investigated,and a long-life CNTs cathode design was introduced.Patterning the CNTs as an array of CNTs island offers a way to eliminate the shielding effects of electrical field.In this way the areas of emitting CNTs are larger,which avoids over-heating on a small emission area.A bonding technique was introduced,the contact between CNTs and substrate was maintained by molecular forces previously,melting metal was introduced as the bonding layer.The mechanical robustness of the CNTs cathode was enhanced while the electrical/thermal resistance was reduced.Performance tests were conducted on the prototype in a high vacuum environment.The prototype produced a current of 0-1 mA with a resolution less than 2μA and the noise level was less than 1μA/Hz^(1/2)@0.01-1 Hz.The prototype was tested by over 550 hours'continuous emitting,showing good stability in long-term use.

关 键 词：碳纳米管 场发射阴极 阵列化设计 边缘效应 转移键合工艺 

分 类 号：V19[航空宇航科学与技术—人机与环境工程]