渍制钪酸盐钡钨阴极脉冲性能的研究
AN INVESTIGATION ON PULSE PROPERTIES OF IMPREGNATED BARIUM SCANDATE DISPENSER CATHODES
-
摘要: 本文对渍制钪酸盐钡钨阴极的脉冲性能作了下述几方面的研究。(1)脉冲发射水平和逸出功分布;(2)脉冲运用下的电子初速分布;(3)脉冲工作比效应;(4)强场下的非常肖特基效应。 本阴极在Tk=850℃下能提供的脉冲发射电流密度大于20A/cm2;平均逸出功=1.7eV;发射的不均匀性与国外报道的M型阴极的相近;在脉冲运用下,电子速度的分散值低于氧化物阴极的。本阴极在场强高于1104V/cm时,出现非常肖特基效应,本文用S值来表征。本阴极的S值明显高于渍制铝酸盐钡钨阴极和L阴极的。造成非常肖特基效应的主要原因是表面逸出功不均匀。在脉冲工作比f=510-3410-2范围内,支取8.8A/cm2时,本阴极有良好的平坦f特性,所以适用于长脉冲、大功率毫米波器件。 最后结合国内外对这种阴极的表面分析结果,对本文的实验结果进行了讨论,这些讨论有助于阐明本阴极的发射机制。
-
关键词:
Abstract: The impregnated barium scandate dispenser cathode used in microwave tulbes, especially in gyrotrons, has been investigated in following aspects: (1) pulse emission property and work function distribution; (2) electron initial velocity distribution in pulse operation; (3) the effect of pulse duration ratio; (4) anomalous Schottky effect under high electric field. Some useful results are obtained: the pulse emission current density is higher than 20 A/cm2 (when t=850℃) ; the anomalous Schottky effect is observed when the electric field is higher than 104V/cm; the cathode has a flat Ja-f property when the pulse duration ratio is in the range of 510-3--410-2 and an emission current density of 8.8A/cm2 is drawn. In the end, the obtained results are discussed in relation to the surface analysis of the cathode. -
白振纲,张洪来,江定健,曾昭俟,电子学通讯,3(1981), 191.[2]张恩虬,电子学通讯,4(1982), 1.[3]杨凌云,王书绅,电子学通讯,4(1982), 384.[4]M. C. Green, H. B. Skinner and R. A. Tuck, Appl., Surf. Sci., 8 (1981), 13.[5]卞彭,电子学通讯,3(1981), 152.[6]G. Herrmann, and S. Wagner著,沈庆垓译,氧化物阴极,商务印书馆,1959,第68页.[7]E. B. Hensley, J. Appl. Phys., 32 (1961), 301.[8]P. L. Meehan and E. A. Coomes, Surf. Sci., 44(1974), 401.[9]D. Jones, Appl. Surf. Sci., 2 (1979), 232.[10]L. Spark and H. P. Philipp,J. Appl. Phys., 24 (1953), 453.[11]汪胜宁,王书绅,杨凌云,电子科学学刊,6(1984), 226.[12]杨凌云,王书绅,电子管技术,1981年第3-4期,第91页.[13]E. S. Ritter, R. H. Ahlert and W. C. Rutledge, J. Appl. Phys., 28 (1957), 156.[14]A. van Oostrum, L. Augustus, Appl. Suf. Sci., 2 (1979), 173.[15]许汴生,电子管技术,1984年,第1期,第7页.[16]Б.П.Никонов. Оксидный Катод, Изд. 《Энергия》,1979, Москва, стр. 72.[17]郭文湘,晶体振荡法测量阴极蒸发率,中国电子学会真空电子学学会第四届学术年会论文摘要汇编,1982,12,上海,第143页.[18]张恩虬,物理学报,25 (1976), 23.[19]R. E. Thomas, T. Pankey, J. W. Gibson and G. A. Hass, Appl. Surf. Sci, 2 (1979), 187.
计量
- 文章访问数: 1611
- HTML全文浏览量: 70
- PDF下载量: 390
- 被引次数: 0