Abstract At present, most of the Ⅲ-Ⅴ semiconductor photocathodes, such as GaAs, GaN and AlGaN photocathodes are activated by Cs/O at room temperature. In order to analyze the influence of different activation conditions on the performance of AlGaN photocathode, and investigate the mechanism of surface activation, five AlGaN photocathodes were activated with different conditions in an ultra-high vacuum system under a pressure of 10−8 Pa. Three samples were activated by Cs/O under different temperatures at room temperature (about 25 °C), high temperature (about 60 °C) and low temperature (about −50 °C), respectively. One sample was activated by Rb/O at room temperature. Besides, one more sample was activated by Cs/O at room temperature to study the stability of AlGaN photocathode after activation. The results show that the performance of AlGaN photocathode could be affected greatly by activation conditions, and the mechanism was analyzed. The effect of excessive Cs treatment after activation on the stability of AlGaN photocathode was studied.

中文翻译：

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超高真空系统中AlGaN光电阴极活化机理研究

摘要 目前，大多数Ⅲ-Ⅴ族半导体光电阴极，如GaAs、GaN和AlGaN光电阴极，大多采用Cs/O在室温下活化。为了分析不同活化条件对AlGaN光电阴极性能的影响，研究表面活化机理，在10-8Pa压力的超高真空系统中，在不同条件下活化了5个AlGaN光电阴极。样品分别在室温（约25°C）、高温（约60°C）和低温（约-50°C）的不同温度下被Cs/O活化。一个样品在室温下被 Rb/O 激活。此外，另外一个样品在室温下用 Cs/O 活化，以研究活化后 AlGaN 光电阴极的稳定性。结果表明，活化条件对AlGaN光电阴极的性能影响较大，并对其机理进行了分析。研究了活化后过量Cs处理对AlGaN光电阴极稳定性的影响。