Effect of amorphous carbon film on secondary electron emission of metal

Hu Xiao-Chuan; Liu Yang-Xi; Chu Kun; Duan Chao-Feng

doi:10.7498/aps.73.20231604

Abstract

Amorphous carbon films have attracted much attention in the field of abnormal discharge of vacuum microwave devices and equipment due to their extremely low secondary electron yields (SEYs). However, the dynamic process and microscopic mechanism of the effect of amorphous carbon film on secondary electron emission are still poorly understood. In this work, a numerical simulation model of the secondary electron emission of amorphous carbon film on copper surface is developed by the Monte Carlo method, which can accurately simulate the dynamic processes of electron scattering and emission of the film and the substrate. The results show that the maximum SEY decreases by about 20% when the film thickness increases from 0 to 1.5 nm. Further increasing the thickness, the SEY no longer decreases. However, when the film is thicker than 0.9 nm, the SEY curve exhibits a double-hump form, but with the thickness increasing to 3 nm, the second peak gradually weakens or even disappears. The electron scattering trajectories and energy distribution of secondary electrons indicate that this double-hump phenomenon is caused by electron scattering in two different materials. Compared with previous models, the proposed model takes into account the change of work function and the effect of interfacial barrier on electron scattering path. Our model can explain the formation of the double-hump of SEY curve and provides theoretical predictions for suppressing the SEY by amorphous carbon film.

Keywords:

Authors and contacts

1.
School of Energy and Electrical Engineering, Chang’an University, Xi’an 710064, China
2.
Xi’an Jiaotong University Health Science Center, Xi’an 710049, China

Corresponding author: Hu Xiao-Chuan, huxc@chd.edu.cn

Funds: Project supported by the China Postdoctoral Science Foundation (Grant No. 2021M702629), the Natural Science Basic Research Plan in Shaanxi Province of China (Grant No. 2023-JC-YB-004), and the Fundamental Research Funds for the Central Universities of China (Grant Nos. 300102383103, 300102383203).

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References

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Cited By

图 1 a-C/Cu的二次电子发射示意图

Figure 1. Schematic diagram of the secondary electron emission of a-C/Cu.

DownLoad: Full-Size Img PowerPoint

图 2 基于MC方法的a-C/Cu二次电子发射模拟流程图

Figure 2. Flow chart of secondary electron emission from a-C/Cu based on the MC method.

DownLoad: Full-Size Img PowerPoint

图 3 电子与a-C和Cu原子的弹性和非弹性散射概率P和电子能量E₀的关系

Figure 3. Relationship between the elastic and inelastic scattering probability P of electron and a-C or Cu atoms and electron energy E₀.

DownLoad: Full-Size Img PowerPoint

图 4 MC模拟结果与文献实验结果的对比

Figure 4. Comparison of our MC simulation results and the reported experimental results.

DownLoad: Full-Size Img PowerPoint

图 5 厚度L对SEY $\delta $的影响　(a)不同L下, $\delta $与$ {E_{{\text{PE}}}} $的关系; (b) ${\delta _{\max1}}$, ${\delta _{\max2}}$, ${E_{\max1}}$和${E_{\max2}}$与L的关系

Figure 5. Effects of the thickness L on the SEY $\delta $: (a) $\delta $vs.$ {E_{{\text{PE}}}} $at different L; (b) ${\delta _{\max1}}$, ${\delta _{\max2}}$, ${E_{\max1}}$ and ${E_{\max2}}$vs. L.

DownLoad: Full-Size Img PowerPoint

图 6 不同厚度L下的电子散射轨迹分布及规律　(a) L = 0 nm; (b) L = 0.9 nm; (c) L = 1.5 nm; (d) L = 2.4 nm; (e) MPD和${P_{{\text{a-C}}}}$与L的关系. 图(a)—(d)中, 灰色点线表示MPD的位置, 红色曲线表示归一化的电子密度分布

Figure 6. Distribution and pattern of electron scattering trajectories with different L: (a) L = 0; (b) L = 0.9 nm; (c) L = 1.5 nm; (d) L = 2.4 nm; (e) MPD and ${P_{{\text{a-C}}}}$ vs. L. In panels (a)–(d), the gray dot line represents the position of the MPD, and the red curve represents the normalized electron density distribution.

DownLoad: Full-Size Img PowerPoint

图 7 入射角度$\theta $对SEY $\delta $的影响　(a) 不同$\theta $下, $\delta $与$ {E_{{\text{PE}}}} $的关系; (b) ${\delta _{\max1}}$, ${\delta _{\max2}}$, ${E_{\max1}}$和${E_{\max2}}$与$\theta $的关系; (c) ${\delta _\Delta }$和${E_\Delta }$与$\theta $的关系. 其中, 图(c)中的内插图为${\delta _\Delta }$和${E_\Delta }$的示意图

Figure 7. Effects of incident angle $\theta $ on the SEY $\delta $: (a) $\delta $ vs. $ {E_{{\text{PE}}}} $ at different $\theta $; (b) ${\delta _{\max1}}$, ${\delta _{\max2}}$, ${E_{\max1}}$and ${E_{\max2}}$ vs. $\theta $; (c) ${\delta _\Delta }$ and ${E_\Delta }$ vs. $\theta $. In panel (c), the interpolation diagram is a schematic diagram of ${\delta _\Delta }$ and ${E_\Delta }$.

DownLoad: Full-Size Img PowerPoint

图 8 不同入射角度$\theta $下的电子的散射轨迹分布及规律(L = 1.5 nm)　(a) $\theta $= 0°; (b) $\theta $= 30°; (c) $\theta $= 60°; (d) $\theta $= 80°; (e) MPD和${P_{{\text{a-C}}}}$与$\theta $的关系. 图(a)—(d)中, 灰色点线表示MPD的位置, 红色曲线表示归一化的电子密度分布

Figure 8. Distribution and pattern of electron scattering trajectories with different $\theta $ (L = 1.5 nm): (a) $\theta $= 0°; (b) $\theta $= 30°; (c) $\theta $= 60°; (d) $\theta $= 80°; (e) the MPD and ${P_{{\text{a-C}}}}$ vs. $\theta $. In panels (a)–(d), the gray dot line represents the position of the MPD, and the red curve represents the normalized electron density distribution.

DownLoad: Full-Size Img PowerPoint

图 9 L对SES的影响　(a) 不同L下的SES; (b) MPE和FWHM与L的关系

Figure 9. Effects of L on the SES: (a) SES curves with different L; (b) MPE and FWHM vs. L.

DownLoad: Full-Size Img PowerPoint

[1]	Kirby R E, King F K 2001 Nucl. Instrum. Methods Phys. Res. , Sect. A 469 1 Google Scholar
[2]	Yater J E 2023 J. Appl. Phys. 133 050901 Google Scholar
[3]	李鹏飞, 袁华, 程紫东, 钱立冰, 刘中林, 靳博, 哈帅, 万城亮, 崔莹, 马越, 杨治虎, 路迪, Reinhold Schuch, 黎明, 张红强, 陈熙萌 2022 物理学报 71 074101 Google Scholar Li P F, Yuan H, Cheng Z D, Qian L B, Liu Z L, Jin B, Ha S, Wan C L, Cui Y, Ma Y, Yang Z H, Lu D, Schuch R, Li M, Zhang H Q, Chen X M 2022 Acta Phys. Sin. 71 074101 Google Scholar
[4]	Valizadeh R, Malyshev O B, Wang S H, Zolotovskaya S A, Allan Gillespie W, Abdolvand A 2014 Appl. Phys. Lett. 105 231605 Google Scholar
[5]	董烨, 刘庆想, 庞健, 周海京, 董志伟 2018 物理学报 67 037901 Google Scholar Dong Y, Liu Q X, Pang J, Zhou H J, Dong Z W 2018 Acta Phys. Sin. 67 037901 Google Scholar
[6]	邓晨晖, 韩立, 王岩, 高召顺, 牛耕 2023 材料导报 37 22030065 Deng C H, Han L, Wang Y, Gao Z S, Niu G 2023 Mater. Rep. 37 22030065
[7]	胡笑钏, 陈彦璋, 孙广哲, 吕毅 2023 高电压技术 49 3803 Google Scholar Hu X C, Chen Y Z, Sun G Z, Lü Y 2023 High Voltage Eng. 49 3803 Google Scholar
[8]	王丹, 贺永宁, 叶鸣, 崔万照 2018 物理学报 67 087902 Google Scholar Wang D, He Y N, Ye M, Cui W Z 2018 Acta Phys. Sin. 67 087902 Google Scholar
[9]	朱香平, 王丹, 汪辉, 周润东, 李相鑫, 洪云帆, 靳川, 韦永林, 罗朝鹏, 赵卫 2022 科学通报 67 2811 Google Scholar Zhu X P, Wang D, Wang H, Zhou R D, Li X X, Hong Y F, Jin C, Wei Y L, Luo C P, Zhao W 2022 Chin. Sci. Bull. 67 2811 Google Scholar
[10]	Li J, Liu B Y, Wu S L, Li Y D, Hu W B 2022 Mater. Lett. 327 133085 Google Scholar
[11]	张宇心, 王一刚, 葛晓琴, 张波, 尉伟, 裴香涛, 范乐, 王勇 2018 真空科学与技术学报 38 1065 Google Scholar Zhang Y X, Wang Y G, Ge X Q, Zhang B, Wei W, Pei X T, Fan L, Wang Y 2018 Chin. J. Vac. Sci. Technol. 38 1065 Google Scholar
[12]	Larciprete R, Grosso D R, Di Trolio A, Cimino R 2015 Appl. Surf. Sci. 328 356 Google Scholar
[13]	Li J, Yi X K, Hu W B, Gao B Y, Li Y D, Wu S L, Lin S, Zhang J T 2019 Materials 12 2631 Google Scholar
[14]	Yu S, Jeong T, Yi W, Lee J, Jin S, Heo J, Kimb J M, Jeon D 2001 Appl. Phys. Lett. 79 3281 Google Scholar
[15]	Ye M, Feng P, Wang D, Song B P, He Y N, Cui W Z 2019 Chin. Phys. B 28 077901 Google Scholar
[16]	Cohen-Tannoudji C, Diu B, Laloe F 1977 Quantum Mechanics (Vol. 1) (Paris: Wiley-VCH Press) pp216–224
[17]	Hu X C, Xiao J, Zhu W, Yu Y X 2018 J. Phys. D: Appl. Phys. 51 385203 Google Scholar
[18]	彭敏, 程文杰, 曹猛 2022 空间电子技术 19 72 Google Scholar Peng M, Cheng W J, Cao M 2022 Space Electron. Technol. 19 72 Google Scholar
[19]	Nguyen H K A, Mankowski J, Dickens J C, Neuber A A, Joshi R P 2018 AIP Adv. 8 015325 Google Scholar
[20]	Joy D C 1991 Scanning Microsc. 5 329
[21]	Bethe H 1930 Ann. Phys. 397 325 Google Scholar
[22]	Cao M, Zhang N, Hu T C, Wang F, Cui W Z 2015 J. Phys. D: Appl. Phs. 48 055501 Google Scholar
[23]	Mott N F 1929 Proc. R. Soc. London, Ser. A 126 79 Google Scholar
[24]	Czyżewski Z, MacCallum D O N, Romig A, Joy D C 1990 J. Appl. Phys. 68 3066 Google Scholar
[25]	Shinotsuka H, Tanuma S, Powell C J, Penn D R 2015 Surf. Interface Anal. 47 871 Google Scholar
[26]	Da B, Li Z Y, Chang H C, Mao S F, Ding Z J 2014 J. Appl. Phys. 116 124307 Google Scholar
[27]	Palik E D 1997 Handbook of Optical Constants of Solids (San Diego: Academic Press) pp837–852
[28]	Inguimbert C, Gibaru Q, Caron P, Angelucci M, Spallino L, Cimino R 2022 Nucl. Instrum. Methods Phys. Res. , Sect. B 526 1 Google Scholar
[29]	Angelucci M, Novelli A, Spallino L, Liedl A, Larciprete R, Cimino R 2020 Phys. Rev. Res. 2 032030 Google Scholar
[30]	张恒, 崔万照 2016 空间电子技术 3 7 Google Scholar Zhang H, Cui W Z 2016 Space Electron. Technol. 3 7 Google Scholar
[31]	胡笑钏, 黄逸清, 陈彦璋, 吕毅 2022 西安交通大学学报 56 144 Google Scholar Hu X C, Huang Y Q, Chen Y Z, Lü Y 2022 J. Xi’an Jiaotong Univ. 56 144 Google Scholar

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