目前市面上的短波長紅外光(SWIR)或中波長紅外光(MWIR)波段的光偵測
器主要皆以 InGaAs、HgCdSe 等材料製作，其成本較為昂貴且無法直接生長於
矽基板上的問題。而 IV 族的鍺錫合金相較於上述兩者材料能夠與矽製成整合，
且為非毒性材料成本也較低，所以近期也成為了熱門的研究。然而，生長一個
高錫含量的鍺錫薄膜也面臨許多的挑戰，如高溫下表面容易產生錫偏析、錫難
以固溶於鍺薄膜中等，所以錫含量難以提升。
這項實驗使用了自製的電漿輔助化學氣相沉積系統，並以四氯化鍺及四氯
化錫作為前驅物，透過四氯化鍺蒸氣及四氯化錫蒸氣和氫原子反應於低溫下(約
100℃)，在矽基板上尋找適合生長高錫含量、高平整度非晶鍺錫薄膜的參數條
件，以及優化鍍膜步驟使其能夠形成鏡面般(Mirror – like)而非霧面(Foggy)的表
面。接著，嘗試藉由掃描式連續光雷射退火處理使其形成單晶鍺錫薄膜，並以
拉曼光普確認其結晶品質，於雷射掃描速度 0.3mm/s 及輔助器加熱溫度 300℃
下，以及在有二氧化矽作為覆蓋層用以提升雷射作用溫度，雷射掃描速度為
3mm/s 及輔助器加熱溫度 300℃下，皆能夠由拉曼光譜看到結晶的峰值出現，
然而結晶性尚未達到良好的品質，卻因為薄膜內含有殘留的氫氣尚未脫附，加
熱時會造成起泡現象導致薄膜破裂，因而被限制住無法繼續提高加熱作用的溫
度來提升結晶性，故必須尋找較高的生長溫度條件，防止氫氣的殘留。
於是本研究將近一步發展使用電漿侷限檔板的方法，於反應腔體前後兩端
加入實心開孔玻璃圓柱，圓孔大小設計為能使氣體通過，但不足以使電子產生
加速撞擊來產生電漿的直徑 5mm 大小，因此形成一個介電質侷限住電漿，以防
止前端進氣口區域消耗過多的四氯化錫前驅物。於此條件下，能夠以較高的溫
度生長鍺錫薄膜，再適當的參數下直接形成單晶且錫含量為 9%的鍺錫薄膜，滿
足能夠用以製作光偵測器的條件。

Currently, the short-wavelength infrared (SWIR) or mid-wavelength infrared (MWIR) photodetectors on the market are mainly made of InGaAs, HgCdSe and other materials, which are expensive and cannot be grown directly on silicon substrates.
Compared with the above two materials, the Group IV germanium-tin alloy can be integrated with silicon, and it is a non-toxic material with lower cost, so it has become popular research recently. However, growing a germanium-tin thin film with a high Sn content also face many challenges, such as the ease of occurrence of Sn segregation at
high temperature, the low bulk solubility of Sn in Ge, etc., so it is difficult to increase the Sn content.
In this work, a home-made plasma-enhanced chemical vapor deposition system was used, and germanium tetrachloride and tin tetrachloride were used as precursors, germanium tetrachloride vapor and tin tetrachloride vapor were reacted with hydrogen atoms at low temperature (About 100℃). Finding the parameter conditions suitable for the growth of high Sn content and high flatness amorphous germanium-tin thin film on silicon substrate and optimize the deposition steps to form a mirror-like surface rather than a foggy surface. Then, try to transform amorphous germanium-tin thin film into
monocrystalline by the scanning of CW laser annealing treatment. Raman spectroscopyand XRD measurements were used to investigate crystallinity. Under the laser scanning speed of 0.3mm/s and the auxiliary heating temperature of 300℃ by heater ; using silicon dioxide as a covering layer to increase the laser action temperature, the laser scanning speed is 3mm/s and the auxiliary heating temperature is 300℃, both of these two conditions can saw the peak showing the crystalline of germanium-tin thin film, but with low crystalline quality. Due to the formation and spallation of blisters occurred, it is limited and cannot continue to increase the heating temperature to improve the crystallinity, so it is necessary to find a better solution. High growth temperature conditions to prevent hydrogen residue.
Therefore, this study will further develop the method of using plasma confinement. Perforated solid cylindrical glass are added to the front and rear ends of the reaction chamber. The diameter of the circular holes is designed in 5mm, allow the gas to pass through but not enough to accelerate the electrons to generate plasma. Thus, forming a
dielectric to confine the plasma to prevent excessive consumption of the tin tetrachloride precursor in the front area. Under this condition, a germanium-tin thin film can be grown at a relatively high temperature, and then a monocrystalline germaniumtin film with a tin content of 9% can be directly formed under appropriate parameters,
which satisfies the conditions for making a photodetector.

摘要 i
Abstract iii
致謝 v
目錄 vi
表目錄 viii
圖目錄 ix
第1 章介紹 1
1-1 研究動機 1
1-2 薄膜生長 2
1-3 鍺錫光偵測器 4
1-4 研究目標 5
第2 章實驗方法介紹 6
2-1 電漿輔助化學氣相沉積(PECVD) 6
2-1-1 前驅物(Precursor) 7
2-1-2 電漿源 8
2-1-3 矽基板清洗 10
2-2 掃描式連續光雷射退火(Scanning CWLA) 10
2-2-1 光源與架設 11
2-2-2 雷射光斑分析(Beam Profile) 11
2-2-3 雷射掃速、加熱時間及能量關係 12
2-3 診斷工具 13
2-3-1 掃描式電子顯微鏡與能量色散 X 射線光譜儀(SEM&EDX) 13
2-3-2 拉曼光譜(Raman Spectroscopy) 14
2-3-3 X 光繞射儀 (X-Ray Diffraction，XRD) 15
第3 章結果與討論 16
3-1 PECVD 控制參數對鍺錫薄膜成長影響 16
3-1-1 錫含量(Sn content) 16
3-1-2 氯含量(Cl Content) 25
3-1-3 錫相分離(Sn Phase Separation) 27
3-2 以 PECVD 在矽基板上成長高錫含量.高平整度非晶鍺錫薄膜 29
3-2-1 溫度平衡步驟 41
3-2-2 預處理步驟 46
3-2-3 穩壓處理 47
3-3 掃描式連續光雷射處理 49
3-4 侷限電漿擋板 PECVD 59
第4 章結論和未來展望 64
4-1 結論 64
4-2 未來展望 65
第5 章Reference 66

J. Kouvetakis, J. Menendez, and A. V. G. Chizmeshya, "TIN-BASED GROUP
IV SEMICONDUCTORS: New Platforms for Opto- and Microelectronics on
Silicon," Annual Review of Materials Research, vol. 36, no. 1, pp. 497-554,
2006, doi: 10.1146/annurev.matsci.36.090804.095159.
[2] S. A. Ghetmiri et al., "Direct-bandgap GeSn grown on silicon with 2230 nm
photoluminescence," Applied Physics Letters, vol. 105, no. 15, p. 151109, 2014,
doi: 10.1063/1.4898597.
[3] J. Mathews et al., "Direct-gap photoluminescence with tunable emission
wavelength in Ge1−ySny alloys on silicon," Applied Physics Letters, vol. 97, no.
22, p. 221912, 2010, doi: 10.1063/1.3521391.
[4] S. Gupta, B. Magyari-Köpe, Y. Nishi, and K. C. Saraswat, "Achieving direct
band gap in germanium through integration of Sn alloying and external strain,"
Journal of Applied Physics, vol. 113, no. 7, p. 073707, 2013, doi:
10.1063/1.4792649.
[5] B. R. Conley et al., "Si based GeSn photoconductors with a 1.63 A/W peak
responsivity and a 2.4 μm long-wavelength cutoff," Applied Physics Letters, vol.
105, no. 22, p. 221117, 2014, doi: 10.1063/1.4903540.
[6] W. Du et al., "Room-temperature electroluminescence from Ge/Ge1-xSnx/Ge
diodes on Si substrates," Applied Physics Letters, vol. 104, no. 24, p. 241110,
2014, doi: 10.1063/1.4884380.
[7] B. Vincent et al., "Characterization of GeSn materials for future Ge pMOSFETs
source/drain stressors," Microelectronic Engineering, vol. 88, no. 4, pp. 342-346,
Apr 2011, doi: 10.1016/j.mee.2010.10.025.
[8] Y. Miao et al., "Review of Si-Based GeSn CVD Growth and Optoelectronic
Applications," Nanomaterials, vol. 11, no. 10, p. 2556, 2021, doi:
10.3390/nano11102556.
[9] N. Bhargava, M. Coppinger, J. Prakash Gupta, L. Wielunski, and J. Kolodzey,
"Lattice constant and substitutional composition of GeSn alloys grown by
molecular beam epitaxy," Applied Physics Letters, vol. 103, no. 4, p. 041908,
2013, doi: 10.1063/1.4816660.
[10] T. Tsukamoto, N. Hirose, A. Kasamatsu, T. Matsui, and Y. Suda, "Effects of
Low-Temperature GeSn Buffer Layers on Sn Surface Segregation During GeSn
Epitaxial Growth," Electronic Materials Letters, vol. 16, no. 1, pp. 9-13, Jan
2020, doi: 10.1007/s13391-019-00179-y.
[11] K. P. Homewood and M. A. Lourenço, "The rise of the GeSn laser," Nature Photonics, vol. 9, no. 2, pp. 78-79, 2015, doi: 10.1038/nphoton.2015.1.
[12] Q. F. Zhang, Y. Liu, J. Yan, C. F. Zhang, Y. Hao, and G. Q. Han, "Theoretical
investigation of tensile strained GeSn waveguide with Si3N4 liner stressor for
mid-infrared detector and modulator applications," Optics Express, vol. 23, no. 6,
pp. 7924-7932, Mar 2015, doi: 10.1364/oe.23.007924.
[13] J. Zheng et al., "Growth of Crystalline Ge1-xSnx Films on Si (100) by
Magnetron Sputtering," ECS Solid State Letters, vol. 3, no. 9, pp. P111-P113,
2014/07/16 2014, doi: 10.1149/2.0081409ssl.
[14] H. Khelidj et al., "Ge(Sn) growth on Si(001) by magnetron sputtering,"
Materials Today Communications, vol. 26, p. 101915, 2021, doi:
10.1016/j.mtcomm.2020.101915.
[15] S. J. Su et al., "Epitaxial growth and thermal stability of Ge1-xSnx alloys on Gebuffered Si(001) substrates," Journal of Crystal Growth, vol. 317, no. 1, pp. 43-
46, Feb 2011, doi: 10.1016/j.jcrysgro.2011.01.015.
[16] M. Oehme, K. Kostecki, M. Schmid, F. Oliveira, E. Kasper, and J. Schulze,
"Epitaxial growth of strained and unstrained GeSn alloys up to 25% Sn," Thin
Solid Films, vol. 557, pp. 169-172, Apr 2014, doi: 10.1016/j.tsf.2013.10.064.
[17] R. Hickey, N. Fernando, S. Zollner, J. Hart, R. Hazbun, and J. Kolodzey,
"Properties of pseudomorphic and relaxed germanium1−xtinx alloys (x < 0.185)
grown by MBE," Journal of Vacuum Science & Technology B, Nanotechnology
and Microelectronics: Materials, Processing, Measurement, and Phenomena,
vol. 35, no. 2, p. 021205, 2017, doi: 10.1116/1.4975149.
[18] J. Rathore, A. Nanwani, S. Mukherjee, S. Das, O. Moutanabbir, and S.
Mahapatra, "Composition uniformity and large degree of strain relaxation in
MBE-grown thick GeSn epitaxial layers, containing 16% Sn," Journal of Physics
D: Applied Physics, vol. 54, no. 18, p. 185105, 2021, doi: 10.1088/1361-
6463/abe1e8.
[19] L. Zhang et al., "Structural Property Study for GeSn Thin Films," Materials, vol.
13, no. 16, p. 3645, 2020, doi: 10.3390/ma13163645.
[20] M. Bauer et al., "Ge–Sn semiconductors for band-gap and lattice engineering,"
Applied Physics Letters, vol. 81, no. 16, pp. 2992-2994, 2002, doi:
10.1063/1.1515133.
[21] F. Gencarelli et al., "Low-temperature Ge and GeSn Chemical Vapor Deposition
using Ge2H6," Thin Solid Films, vol. 520, no. 8, pp. 3211-3215, Feb 2012, doi:
10.1016/j.tsf.2011.10.119.
[22] J. Margetis et al., "Growth and Characterization of Epitaxial Ge1-XSnx Alloys
and Heterostructures Using a Commercial CVD System," ECS Transactions, vol.
64, no. 6, pp. 711-720, 2014/08/12 2014, doi: 10.1149/06406.0711ecst.
[23] W. Dou et al., "Investigation of GeSn Strain Relaxation and Spontaneous
Composition Gradient for Low-Defect and High-Sn Alloy Growth," Scientific
Reports, vol. 8, no. 1, 2018, doi: 10.1038/s41598-018-24018-6.
[24] W. Dou et al., "Crystalline GeSn growth by plasma enhanced chemical vapor
deposition," Opt. Mater. Express, vol. 8, no. 10, pp. 3220-3229, 2018/10/01
2018, doi: 10.1364/OME.8.003220.
[25] B. Alharthi et al., "Low temperature epitaxy of high-quality Ge buffer using
plasma enhancement via UHV-CVD system for photonic device applications,"
Applied Surface Science, vol. 481, pp. 246-254, 2019/07/01/ 2019, doi:
https://doi.org/10.1016/j.apsusc.2019.03.062.
[26] B. Claflin, G. J. Grzybowski, M. E. Ware, S. Zollner, and A. M. Kiefer, "Process
for Growth of Group-IV Alloys Containing Tin by Remote Plasma Enhanced
Chemical Vapor Deposition," (in English), Frontiers in Materials, Original
Research vol. 7, 2020-March-18 2020, doi: 10.3389/fmats.2020.00044.
[27] D. Zhang et al., "High-responsivity GeSn short-wave infrared p-i-n
photodetectors," Applied Physics Letters, vol. 102, no. 14, p. 141111, 2013, doi:
10.1063/1.4801957.
[28] M. Oehme et al., "GeSn/Ge multiquantum well photodetectors on Si substrates,"
Opt. Lett., vol. 39, no. 16, pp. 4711-4714, 2014/08/15 2014, doi:
10.1364/OL.39.004711.
[29] Y. Dong et al., "Suppression of dark current in germanium-tin on silicon p-i-n
photodiode by a silicon surface passivation technique," Optics Express, vol. 23,
no. 14, p. 18611, 2015, doi: 10.1364/oe.23.018611.
[30] T. Pham et al., "Systematic study of Si-based GeSn photodiodes with 2.6 um
detector cutoff for short-wave infrared detection," Optics Express, vol. 24, no. 5,
pp. 4519-4531, 2016/03/07 2016, doi: 10.1364/OE.24.004519.
[31] Y. Dong et al., "Two-micron-wavelength germanium-tin photodiodes with low
dark current and gigahertz bandwidth," Optics Express, vol. 25, no. 14, p. 15818,
2017, doi: 10.1364/oe.25.015818.
[32] H. Tran et al., "High performance Ge0.89Sn0.11photodiodes for low-cost
shortwave infrared imaging," Journal of Applied Physics, vol. 124, no. 1, p.
013101, 2018, doi: 10.1063/1.5020510.
[33] H. Tran et al., "Si-Based GeSn Photodetectors toward Mid-Infrared Imaging
Applications," ACS Photonics, vol. 6, no. 11, pp. 2807-2815, 2019, doi:
10.1021/acsphotonics.9b00845.
[34] M. Li et al., "Sn composition graded GeSn photodetectors on Si substrate with
cutoff wavelength of 3.3 μm for mid-infrared Si photonics," Applied Physics
Letters, vol. 120, no. 12, p. 121103, 2022, doi: 10.1063/5.0084940.
[35] P. C. Grant et al., "UHV-CVD growth of high quality GeSn using SnCl4: from
material growth development to prototype devices," Opt. Mater. Express, vol. 9,
no. 8, pp. 3277-3291, 2019/08/01 2019, doi: 10.1364/OME.9.003277.
[36] Z. C. Holman, C.-Y. Liu, and U. R. Kortshagen, "Germanium and Silicon
Nanocrystal Thin-Film Field-Effect Transistors from Solution," Nano Letters,
vol. 10, no. 7, pp. 2661-2666, 2010, doi: 10.1021/nl101413d.
[37] T. Tsukamoto, N. Hirose, A. Kasamatsu, T. Mimura, T. Matsui, and Y. Suda,
"Investigation of Sn surface segregation during GeSn epitaxial growth by Auger
electron spectroscopy and energy dispersive x-ray spectroscopy," Applied
Physics Letters, vol. 106, no. 5, p. 052103, 2015, doi: 10.1063/1.4907863.
[38] R. Chen et al., "Material characterization of high Sn-content, compressivelystrained GeSn epitaxial films after rapid thermal processing," Journal of Crystal
Growth, vol. 365, pp. 29-34, 2013/02/15/ 2013, doi:
https://doi.org/10.1016/j.jcrysgro.2012.12.014.
[39] L. Wang et al., "Effects of Annealing on the Behavior of Sn in GeSn Alloy and
GeSn-Based Photodetectors," IEEE Transactions on Electron Devices, vol. 67,
no. 8, pp. 3229-3234, 2020, doi: 10.1109/TED.2020.3004123.
[40] X. Zhang et al., "Crystal Quality Improvement of GeSn Alloys by Thermal
Annealing," Ecs Solid State Letters, vol. 3, no. 10, pp. P127-P130, 2014, doi:
10.1149/2.0101410ssl.
[41] J. Aubin and J. M. Hartmann, "GeSn growth kinetics in reduced pressure
chemical vapor deposition from Ge2H6 and SnCl4," Journal of Crystal Growth,
vol. 482, pp. 30-35, 2018/01/15/ 2018, doi:
https://doi.org/10.1016/j.jcrysgro.2017.10.030.
[42] P. C. Grant et al., "Comparison study of the low temperature growth of dilute
GeSn and Ge," Journal of Vacuum Science & Technology B, Nanotechnology
and Microelectronics: Materials, Processing, Measurement, and Phenomena,
vol. 35, no. 6, p. 061204, 2017, doi: 10.1116/1.4990773.
[43] L. Zhang et al., "Raman scattering study of amorphous GeSn films and their
crystallization on Si substrates," Journal of Non-Crystalline Solids, vol. 448, pp.
74-78, 2016/09/15/ 2016, doi: https://doi.org/10.1016/j.jnoncrysol.2016.07.007.
[44] V. R. D'Costa, J. Tolle, R. Roucka, C. D. Poweleit, J. Kouvetakis, and J.
Menendez, "Raman scattering in Ge1-ySny alloys," Solid State Communications, vol. 144, no. 5-6, pp. 240-244, Nov 2007,doi:10.1016/j.ssc.2007.08.020.
[45] S. J. Su et al., "The contributions of composition and strain to the phonon shift in Ge1-xSnx alloys," Solid State Communications, vol. 151, no. 8, pp. 647-650, Aprl 2011, doi: 10.1016/j.ssc.2011.01.017.