由于GaN光电阴极的突出性能, 其在紫外探测方面有着广泛的应用。 文章在超高真空激活系统中, 对GaN样品进行了Cs/O激活实验, 并分析了激活后反射式的量子效率: 在240～350 nm的紫外波段内, 量子效率约在30%～10%之间, 曲线较为平坦, 在240 nm处达到30%的最大值, 与国外结果对比后发现, 本文获得的GaN光电阴极量子效率在短波段尚有不足。 研究了GaN(0001)表面的原子排列, 利用3D模拟了表面原子排列模型, 并推测了Cs在其表面的吸附情况。

GaN photocathode has a wide applicaion in ultraviolet detection because of the outstanding performance. GaN photocathode was activated in ultrahigh vacuum (UHV) system by Cs/O, and the reflection-mode quantum efficiency (QE) was analyzed. The QE is 30%～10% corresponding to the wavelength 240～350 nm , and the QE curve is flat. The QE reaches the maximum of 30% at 240 nm. Compared with the abroad result, the QE obtained by us is still inadequate at the short wavelength. The atom arrangement of GaN (0001) was studied. The atom arrangement on the surface was simulated by 3D, and in this way the adsorption of Cs on the GaN(0001) was speculated.