半导体光电阴极的研究进展

张益军

半导体光电阴极的研究进展

张益军

南京理工大学电子工程与光电技术学院, 江苏南京 210094

基金项目:

国家自然科学基金 U2141239

国家自然科学基金 61771245

微光夜视技术重点实验室基金 J20200102

详细信息

作者简介:
张益军（1984-），男，博士，副教授，博士生导师，主要从事光电发射材料与器件研究。E-mail: zhangyijun423@njust.edu.cn

中图分类号: TN223
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- 被引次数: 0
出版历程
- 收稿日期: 2022-07-04
- 修回日期: 2022-07-19
- 刊出日期: 2022-08-20

Progress in Research on Semiconductor Photocathodes

ZHANG Yijun

School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China

摘要

摘要: 半导体光电阴极具有量子效率高、暗电流小的优点，被广泛应用于光电倍增管、像增强器等各类真空光电探测和成像器件，促进了极弱光的超快探测和成像技术的发展。另外作为能够产生高品质电子束的真空电子源，用于加速器光注入器、电子显微镜等科学装置。本文首先介绍了目前常用半导体光电阴极的分类以及在真空光电探测成像、真空电子源领域的具体应用。然后对碱金属碲化物光电阴极、碱金属锑化物光电阴极、GaAs光电阴极三类典型半导体光电阴极的制备技术进行了总结，并介绍了微纳结构、低维材料、单晶外延等新技术在半导体光电阴极研制中的应用。最后对半导体光电阴极的技术发展进行了展望。
- 光电阴极 /
- 碱金属碲化物 /
- 碱金属锑化物 /
- GaAs
Abstract: Semiconductor photocathodes with high quantum efficiency and low dark current are widely used in various vacuum photoelectric detection and imaging devices, such as photomultiplier tubes and image intensifiers, promoting the development of ultrafast detection and imaging technology for extremely weak light. Vacuum electron sources capable of producing high-quality electron beams are used in accelerator photoinjectors, electron microscopes, and other scientific equipment. First, this review introduces the classification of semiconductor photocathodes and their applications in the fields of vacuum photoelectric detection and imaging and vacuum electron sources. Then, preparation techniques for three types of typical semiconductor photocathodes, namely, alkali telluride, alkali antimonide, and GaAs photocathodes, are summarized. Subsequently, applications of new technologies, such as micro-nano structures, low-dimensional materials, and single-crystal epitaxy, in the development of semiconductor photocathodes are introduced. Finally, the technical development of the semiconductor photocathodes is discussed.
- photocathode /
- alkali telluride /
- alkali antimonide /
- GaAs

HTML全文

图 1 常用半导体光电阴极按照长波截止波长的分类

Figure 1. Classification of common semiconductor photocathodes according to longwave cut-off wavelength

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图 2 几种常用半导体光电阴极的透射式光谱响应曲线^[12-14]：(a) 碱金属碲化物、碱金属锑化物和GaAs类光电阴极；(b) 紫外光电阴极

Figure 2. Transmission-mode spectral response curves of several common semiconductor photocathodes^[12-14]: (a) Alkali telluride, alkali antimonide, and GaAs-based photocathodes; (b) Ultraviolet photocathodes

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图 3 半导体光电阴极在光电探测成像领域的应用

Figure 3. Application of semiconductor photocathode in the field of photoelectric detection and imaging

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图 4 半导体光电阴极在真空电子源领域的应用

Figure 4. Application of semiconductor photocathode in the field of vacuum electron source

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图 5 金属基底上碱金属碲化物光电阴极的制备：(a) 装置示意图^[34]；(b) 共沉积法的工作稳定性^[32]；(c) K-Cs-Te光电阴极的制备工艺^[34]；(d) K-Cs-Te光电阴极的工作稳定性^[35]

Figure 5. Preparation of alkali telluride photocathode on metal substrate: (a) Schematic diagram of setup^[34]; (b) Operation stability of co-deposition method^[32]; (c) Preparation process of K-Cs-Te photocathode^[34]; (d) Operation stability of K-Cs-Te photocathode^[35]

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图 6 玻璃基底上碱金属碲化物光电阴极的制备装置示意图^[37]

Figure 6. Schematic diagram of preparation setup for alkali telluride photocathode on glass substrate^[37]

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图 7 采用共沉积法制备的K₂CsSb光电阴极^[44]：(a) 表面粗糙度；(b) 量子效率

Figure 7. K₂CsSb photocathode prepared by co-deposition method^[44]: (a) Surface roughness; (b) Quantum efficiency

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图 8 采用变掺杂技术制备的K₂CsSb光电阴极^[45]：(a) 结构示意图；(b) K/Sb共蒸镀；(c) Cs蒸镀；(d) 量子效率曲线

Figure 8. K₂CsSb photocathode prepared by variably-doped technique^[45]: (a) Structural diagram; (b) K/Sb co-deposition step; (c) Cs evaporation step; (d) Quantum efficiency curves

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图 9 Na-K-Sb光电阴极和Na-K-Sb-Cs光电阴极的制备：(a) 停止进Na后的K/Sb交替激活^[46]；(b) Na-K-Sb表面的Cs/Sb交替激活^[47]

Figure 9. Preparation of Na-K-Sb photocathode and Na-K-Sb-Cs photocathode: (a) K/Sb alternate activation after stopping Na^[46]; (b) Cs/Sb alternate activation on Na-K-Sb surface^[47]

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图 10 GaAs光电阴极Cs/O激活过程^[54]：(a) O过量激活法；(b) Cs适中过量法；(c) 名古屋Cs完全过量法；(d) 改进Cs完全过量法

Figure 10. Cs/O activation process of GaAs photocathode^[54]: (a) O excess activation method; (b) Cs moderate excess method; (c) Nagoya Cs complete-overdose method; (d) Improved Cs complete-excess method

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图 11 GaAs光电阴极Cs/NF₃激活过程^[58]：(a) 激活过程中光电流变化；(b) 连续光照下光电流衰减

Figure 11. Cs/NF₃ activation process of GaAs photocathode^[58]: (a) photocurrent change during activation; (b) photocurrent decay under continuous illumination

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图 12 采用Sb源和Te源的GaAs光电阴极激活过程^[64-65]：(a) Cs-Sb激活；(b) Cs-O-Sb激活；(c) Cs-Sb-O激活；(d) Cs-Te激活；(e) Cs-O-Te激活

Figure 12. Activation process of GaAs photocathodes using Sb and Te sources^[64-65]: (a) Cs-Sb activation; (b) Cs-O-Sb activation; (c) Cs-Sb-O activation; (d) Cs-Te activation; (e) Cs-O-Te activation

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图 13 采用透射衍射光栅结构的多碱光电阴极^[68]：(a) 结构示意图；(b) 光谱响应提升效果

Figure 13. Multi-alkali photocathode with transmission diffraction grating structure^[68]: (a) Structure diagram; (b) Spectral response improvement

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图 14 石墨烯应用于K₂CsSb光电阴极制备：(a) 透-反射真空器件^[69]；(b) 不同基底量子效率提高效果^[70]

Figure 14. Graphene used in the preparation of K₂CsSb photocathode: (a) Transmission-reflection mode vacuum tube^[69]; (b) QE improvement on different substrates^[70]

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图 15 单晶Cs₃Sb光电阴极的制备^[72]：(a) 外延生长过程；(b) 量子效率

Figure 15. Preparation of single-crystal Cs₃Sb photocathode^[72]: (a) Epitaxial growth process; (b) Quantum efficiency

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