Rb_2Te(Cs)日盲紫外光电阴极研究

Study on Rb_2Te(Cs) Solar Blind Ultraviolet Cathode

简述了Rb2Te（Cs）日盲紫外阴极的制作工艺并制作了Rb2Te（Cs）日盲紫外阴极样品。测量了Rb2Te（Cs）日盲紫外阴极样品的光谱响应、光谱反射率和250nm波长激发条件下的荧光谱。测量结果表明，在现有工艺条件下，Rb2Te（Cs）日盲紫外阴极的灵敏度高于cs2Te日盲紫外阴极，与Cs2Te日盲紫外阴极相比，光谱响应的峰值波长更短，位于250nm，而长波截止波长位于312nm。另外Rb2Te（Cs）日盲紫外阴极的短波日盲特性更好，633nm的光谱灵敏度为1015mA／W的数量级，较Cs2Te日盲紫外阴极低两个数量级。光谱反射率测量结果表明，Rb2Te（Cs）日盲紫外阴极的光谱反射率在200~400nm的波长范围内均高于Cs2Te日盲紫外阴极，而在400~600nm的波长范围内，反射率却低于Cs2Te日盲紫外阴极。Rb2Te（Cs）日盲紫外阴极的光谱反射率曲线与Cs2Te日盲紫外阴极的光谱反射率曲线相比较，曲线的形状相似，反射干涉加强峰的波长基本相同，由此可推断出Rb：Te（Cs）紫外阴极的折射率与Cs2Te紫外阴极的折射率基本相同，仅在长波范围内稍有区别。荧光谱的测试结果表明，在同样条件下，在200~450nm的波长范围内，Rb2Te（Cs）紫外阴极的荧光弱于Cs2Te紫外阴极的荧光，原因是Rb2Te（Cs）阴极的光谱反射率高于Cs2Te紫外阴极的光谱反射率，因此光吸收更少，导致荧光更弱。所以Rb2Te（Cs）日盲紫外阴极同Cs2Te日盲紫外阴极的性能类似，均可用于日盲紫外探测成像器件。

In this paper, the processing technology of Rb2Te（Cs） solar blind ultraviolet cathode is described and samples of Rb2Te（Cs） solar blind ultraviolet cathode were produced. The spectral response, spectral reflectance and the fluorescence spectra under the excitation condition of 250 nm wavelength of Rb2Te（Cs） solar blind ultraviolet cathode samples were measured. The findings suggest that under the existing technological condition, the sensitivity of Rb2Te（Cs） solar blind ultraviolet cathode is greater than that of Cs2Te; as compared with Cs2Te solar blind ultraviolet cathode, the peak wavelength in spectral response is shorter at 250 nm, while the cutoff wavelength of long wave is at 315 nm. In addition, Rb2Te（Cs） solar blind ultraviolet cathode has better solar blind property; the spectral sensitivity at 633 nm is ranked at the order of magnitude of 10-5 mA/W, two order of magnitudes lower than that of Cs2Te solar blind ultraviolet cathode. In terms of spectral reflectance, the findings show that the spectral reflectance of Rb2Te（Cs） solar blind ultraviolet cathode is higher than that of Cs2Te solar blind ultraviolet cathode within the scope of 200-400 nm wavelength, and is lower than that of Cs2Te solar blind ultraviolet cathode within the scope of 400-600 nm wavelength.The spectral reflectance curves of Rb2Te（Cs） solar blind ultraviolet cathode and Cs2Te solar blindultraviolet cathode are similar in shape, and the peaks in spectral reflectance curve of Rb2Te（Cs） solar blind ultraviolet cathode are basically same to the peaks in spectral reflectance curve of Cs2Te solar blind ultraviolet cathode. It is concluded that the refractive index of Rb2Te（Cs） solar blind ultraviolet cathode is basically same as that of Cs2Te solar blind ultraviolet cathode, only small difference in the range of longer wavelength. The findings on fluorescence spectra indicate that under the same condition and within the scope of 200-450 nm wavelength, the fluorescence of RbzTe（Cs） ultraviolet cathode is more weaker than that of Cs2Te ultraviolet cathode, as the reflectance of Rb2Te （Cs） cathode is higher than that of Cs2Te ultraviolet cathode, the more the photo absorption, the more intense the fluorescence. Thus, the properties of Rb2Te（Cs） solar blind ultraviolet cathode are similar to those of Cs2Te solar blind ultraviolet cathode, and both cathodes can be applied to image device for solar blind ultraviolet detection.