热扩散阴极微区热电子发射特征研究
|
摘要
在微米尺度开展热扩散阴极热电子发射特征研究,对了解阴极电子发射过程和理解阴极发射机理有一定的参考价值。本文利用深紫外激光光发射/热发射电子显微镜系统,对浸渍钡钨阴极、覆膜浸渍扩散阴极、浸渍钪酸盐阴极以及新型浸渍钪型阴极,开展了光电子、热电子显微成像分析。结果显示,浸渍钡钨阴极的热电子发射区域主要位于表面局部孔隙中;覆膜浸渍扩散阴极的电子发射区域沿孔隙向覆膜的钨颗粒表面延伸,阴极发射面积明显增加;浸渍钪酸盐阴极与新型浸渍钪型阴极表面拥有一定数量的高发射点,浸渍钪酸盐阴极的高发射点几乎都分布在阴极表面的钨颗粒边缘,而新型浸渍钪型阴极的高发射点不仅存在于钨颗粒边缘,同时也出现在部分钨颗粒表面。
The research on electron emission characteristics of thermal dispenser cathodes in micro-scale has certain reference value for understanding electron emission process and cathode emission mechanism.In this work,DUV-PEEM/TEEM is used to carry out photo emission electrons and thermal emission electrons imaging analysis for impregnated Ba-W cathode,coated impregnated dispenser cathode,impregnated scandate cathode and new impregnated scandium cathode,respectively.The results show that the electron emission of impregnated Ba-W cathode is mainly located at local pores.For coated impregnated dispenser cathodes,as emission regions extend from pores to tungsten particles,the cathode emission areas increase significantly.In addition,the surfaces of impregnated scandate cathodes or new impregnated scandium cathodes have a certain amount of high emission spots.The high emission spots of impregnated scandate cathodes are almost entirely distributed on the edges of tungsten particles,while the high emission spots of new impregnated scandium cathodes are distributed on both the edges and some surfaces of tungsten particles.
The research on electron emission characteristics of thermal dispenser cathodes in micro-scale has certain reference value for understanding electron emission process and cathode emission mechanism.In this work,DUV-PEEM/TEEM is used to carry out photo emission electrons and thermal emission electrons imaging analysis for impregnated Ba-W cathode,coated impregnated dispenser cathode,impregnated scandate cathode and new impregnated scandium cathode,respectively.The results show that the electron emission of impregnated Ba-W cathode is mainly located at local pores.For coated impregnated dispenser cathodes,as emission regions extend from pores to tungsten particles,the cathode emission areas increase significantly.In addition,the surfaces of impregnated scandate cathodes or new impregnated scandium cathodes have a certain amount of high emission spots.The high emission spots of impregnated scandate cathodes are almost entirely distributed on the edges of tungsten particles,while the high emission spots of new impregnated scandium cathodes are distributed on both the edges and some surfaces of tungsten particles.
引文
[1]Gilmour A S,Jr.丁耀根,张兆传等译.速调管、行波管、磁控管、正交场放大器和回旋管[M].北京:国防工业出版社,2012.
[2]Aurelius S.Activation Process of Impregnated Dispenser Cathode Viewed in the Large-screen Emission Microscope[J].International Journal of Electronics,1962,13(5):401-416.
[3]Vaughn J M,Jamison K D,Kordesch M E.In Situ Emission Microscopy of Scandium/Scandium-Oxide and Barium/Barium-Oxide Thin Films on Tungsten[J].IEEE Transactions on Electron Devices,2009,56(5):794-798.
[4]Liu Yanwen,Tian Hong,Han Yong,et al.Study on the Emission Properties of the Impregnated Cathode With Nanoparticle Films[J].IEEE Transactions on Electron Devices,2012,59(12):3618-3624.
[5]Fukidome H,Yoshimura M,Ueda K.Evaporation and Thermionic Emission Processes of Pb/W(110)Imaged In Situ by Emission Electron Microscopy[J].Japanese Journal of Applied Physics,2006,45(1A):70-72.
[6]Berger M H,Back T C,Soukiassian P,et al.Local Investigation of the Emissive Properties of LaB6-ZrB2 Eutectics[J].Journal of Materials Science,2017,52:5537-5543.
[7]Brodie I,Vancil B.Electron Emission Microscopy of Scandate Cathode Emission Sites[C].2016IEEE International Vacuum Electronics Conference(IVEC),2016.
[8]任峰,阴生毅,卢志鹏,等.深紫外激光光发射与热发射电子显微镜在热扩散阴极研究中的应用[J].物理学报,2017,66(18):187901.
[9]Lu Zhipeng,Zhang Zhaochuan,Yin Shengyi,et al.Thermoelectron Emission Microscopy of Zr-coated Scandate Disperse Cathode[C].2018IEEE International Vacuum Electronics Conference(IVEC),2018.
[10]Yin Shengyin,Zhang Zhaochuan,Peng Zhen,et al.A New Impregnated Dispenser Cathode[J].IEEE Transactions on Electron Devices,2013,60(12):4258-4262.
[2]Aurelius S.Activation Process of Impregnated Dispenser Cathode Viewed in the Large-screen Emission Microscope[J].International Journal of Electronics,1962,13(5):401-416.
[3]Vaughn J M,Jamison K D,Kordesch M E.In Situ Emission Microscopy of Scandium/Scandium-Oxide and Barium/Barium-Oxide Thin Films on Tungsten[J].IEEE Transactions on Electron Devices,2009,56(5):794-798.
[4]Liu Yanwen,Tian Hong,Han Yong,et al.Study on the Emission Properties of the Impregnated Cathode With Nanoparticle Films[J].IEEE Transactions on Electron Devices,2012,59(12):3618-3624.
[5]Fukidome H,Yoshimura M,Ueda K.Evaporation and Thermionic Emission Processes of Pb/W(110)Imaged In Situ by Emission Electron Microscopy[J].Japanese Journal of Applied Physics,2006,45(1A):70-72.
[6]Berger M H,Back T C,Soukiassian P,et al.Local Investigation of the Emissive Properties of LaB6-ZrB2 Eutectics[J].Journal of Materials Science,2017,52:5537-5543.
[7]Brodie I,Vancil B.Electron Emission Microscopy of Scandate Cathode Emission Sites[C].2016IEEE International Vacuum Electronics Conference(IVEC),2016.
[8]任峰,阴生毅,卢志鹏,等.深紫外激光光发射与热发射电子显微镜在热扩散阴极研究中的应用[J].物理学报,2017,66(18):187901.
[9]Lu Zhipeng,Zhang Zhaochuan,Yin Shengyi,et al.Thermoelectron Emission Microscopy of Zr-coated Scandate Disperse Cathode[C].2018IEEE International Vacuum Electronics Conference(IVEC),2018.
[10]Yin Shengyin,Zhang Zhaochuan,Peng Zhen,et al.A New Impregnated Dispenser Cathode[J].IEEE Transactions on Electron Devices,2013,60(12):4258-4262.