氮化硼复合陶瓷表面二次电子发射抑制  

Modulation of Secondary Electron Emission from Boron Nitride Composite Ceramics

作　　者：姚璐 欧阳林杰 王丹[1] 陈继新[3] 贺永宁[1] 徐亚男 YAO Lu;OUYANG Linjie;WANG Dan;CHEN Jixin;HE Yongning;XU Yanan(School of Microelectronics,Xi’an Jiaotong University,Xi’an 710049,China;ZhongKe Atomically Precise Manufacturing Technology Co.,Ltd.,Xi’an 710119,China;Shenyang National Laboratory for Materials Science,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China;Shanghai Institute of Space Propulsion,Shanghai Engineering Research Center of Space Engine,Shanghai 201112,China)

机构地区：[1]西安交通大学微电子学院,西安710049 [2]西安中科原子精密制造科技有限公司,西安710119 [3]中国科学院金属研究所沈阳材料科学国家研究中心,沈阳110016 [4]上海推进技术研究所上海空间发动机工程技术研究中心,上海201112

出　　处：《高电压技术》2023年第9期3848-3855,共8页High Voltage Engineering

基　　金：国家自然科学基金(62101425);陕西省重点研发计划(2021LLRH-03);中国科学院重点部署项目(ZDRW-XH-2021-6);国家重点研发计划(2016YFB0303804);上海市科学技术委员会(17DZ2280800)。

摘　　要：二次电子产额δ是影响霍尔推进器鞘层的关键参数之一。为了降低推进器通道壁面常用材料BN−SiO_(2)复合陶瓷的表面δ,通过激光刻蚀工艺和表面镀层技术对表面δ进行了调控。使用脉冲红外光纤激光器在材料表面构造微阵列结构,使用激光扫描显微镜对表面结构表征,表面δ测试方法采用收集极法。δ测试结果表明:激光功率10 W且扫描周期50时,样品表面形成的周期性微阵列结构δ抑制效果较为理想,两种不同质量配比的复合陶瓷表面δ峰值分别由2.62和2.38降低至1.55和1.46。使用磁控溅射在上述微结构表面沉积一层TiN薄膜,δ得到进一步抑制。使用扫描电子显微镜对薄膜表面表征,表面颗粒呈现三棱锥结构。结果表明:溅射功率100 W且时长90 min时,TiN膜厚约为246 nm,镀覆该厚度TiN薄膜的两组微结构样品δ峰值分别由1.55和1.46降低至0.82和0.76,相比原始表面大幅降低。该研究通过表面刻蚀和薄膜沉积工艺,大幅降低了BN−SiO_(2)复合陶瓷表面的δ,研究工作对于特定工作场景中开展低δ表面处理工艺研究具有工程应用价值。Secondary electron emission yield(δ)is one of the key parameters affecting the Hall thruster sheath.In this study,we employed two technologies,laser etching and surface coating,to suppressδof BN-SiO_(2).The construction of microarray structures on the surface of the sample is achieved by using a pulsed infrared fiber laser.The characterization of the surface structure is achieved by the laser scanning microscopy.The measurement ofδrelies on the collecting method.The results show that the optimumδsuppression is achieved by the process parameters of 10 W laser power and 50 scanning cycles.Theδpeak values of two BN-SiO_(2) samples are reduced from 2.62 and 2.38 to 1.55 and 1.46,respectively.Subsequently,a TiN thin film was deposited on the laser etched microstructures by utilizing the magnetron sputtering to realize a betterδsuppression.The characterization results show that a plenty of nanoscale trigonal structures distribute on the surface of the fabricated TiN film,and the film thickness is about 246 nm.For the BN-SiO_(2) microstructures,after coating the TiN film,theδpeak values of two samples are reduced from 1.55 and 1.46 to 0.82 and 0.76,which achieves a significantδsuppression compared to the original surface.In this study,theδof BN-SiO_(2) ceramic is significantly reduced by surface etching and TiN film deposition.The study is of significance for engineering applications to achieve lowδsurfaces in some necessary occasions.

关 键 词：氮化硼 二次电子发射 霍尔推进器 激光刻蚀 氮化钛 

分 类 号：V439.2[航空宇航科学与技术—航空宇航推进理论与工程] O462.2[理学—电子物理学]