场发射冷阴极的稳定性和可靠性研究

A Study on the Stability and Reliability of Field Emission Cathodes

讨论了清洁处理（ＣＰ）对ＦＥＣ电子发射的影响。实验结果表明，ＣＰ能有效激活长时间存放于恶劣环境的ＦＥＣ的电子发射；还研究了场热成形（ＦＨＦ）对提高ＦＥＣ电子发射稳定性和可靠性的作用。实验发现，正确选择阳极材料并进行必要的真空除气，对防止尖端由于真空电弧而造成的破坏有重要意义。ＦＨＦ对尖端表面的微观状态具有强烈的影响，具体表现在尖端表面有效功函数φ和尖端场增强因子β的改变上。经过ＣＰ和ＦＨＦ处理，得到了发射稳定、可靠性好的ＦＥＣ。

The effects of cleaning process (CP) on the performance of FEC′s that have been stored under adverse conditions for a long time are discussed. Experimental results show that CP can effectively activate such FEC′s for electron emission. Changes in microstate of the FEC surface during field heat forming(FHF) are also investigated. It is found that a thorough vacuum outgassing of carefully selected anode materials can keep the FEC tips from damage caused by vacuum arc discharges. It has been shown that the effective work function φ and the field enhancement factor β of FEC′s may vary with different FHF processes. Finally, stable and reliable FEC′s have been fabricated with proper CP and FHF processes.