【摘要】 利用自行研制的“光电阴极多信息量测试系统”首次对国产三代微光管中的GaAs光电阴极的均匀性进行了光谱响应测试 ,结果表明该国产三代微光管存在明显的非均匀性。利用曲线拟合方法估算了GaAs光电阴极的材料性能参数 ,发现表面逸出概率不一致是非均匀性的主要原因 ,GaAs材料的少子扩散长度 (1 1 2～ 1 82 ) μm ,与阴极厚度相当 ,后界面复合速率在 (1× 1 0 5～ 1× 1 0 6 )cm/s之间 ,它限制了阴极灵敏度的提高更多还原

【Abstract】 Uniformity of the low light level (LLL) photo cathode tubes,made of GaAs/AlGaAs/GaAs films,was studied by measuring its spectral response with our lab made multi functional photo cathode evaluation system.The technical performance of the materials was evaluated by data fitting.The results show that pronounced non uniformity exists,possibly resulting from the variations in the surface emission probabilities.The diffusion length of the minority carriers in GaAs films was estimated to be (1 12～1 82) μm,roughly close to the film thickness.However,high recombination rate at the interface of GaAs film and the substrate,(1×10 5～1×10 6) cm/s,may inversely affect the sensitivity of the tube.更多还原