鍺錫半導體已經是四族主動元件的主要材料，在這論文中，利用快速熱熔磊晶法在矽基板上製作鍺錫金半金漸變式光偵測器，利用快速熱熔磊晶法可以製作出3~4%的鍺錫合金。
利用SAD和EDS方法分別分析錫在條狀鍺的晶體結構和濃度分布，由分析結果可以發現利用快速熱熔磊晶法製作出的鍺錫合金為單晶結構，而且結晶品質良好。此外，透過拉曼頻譜分析，同樣分析出單晶的鍺錫合金，並且得到錫在鍺錫合金中的濃度分布。最後，透過量測元件光電響應及光導電性的公式，求得錫在金屬電極下的濃度分布。

Germanium-Tin (GeSn) semiconductor alloy has been considered as a candidate for implementing active Group IV optoelectronics. In this thesis, a Ge1-xSnx metal-semiconductor-metal (MSM) photodetector fabricated on Si substrate by rapid melt growth method with graded Sn concentration up to 5-10 %, which is higher than the solid solubility (~ 1 %) of Sn in Ge is demonstrated.
The crystal orientation and elemental composition of the GeSn alloy are characterized by selected area diffraction (SAD) pattern and energy dispersion spectroscopy (EDS), showing a monocrystalline semiconductor quality and Sn concentration profile. This crystal quality of GeSn alloy is also investigated by Raman spectroscopy. Finally, we measure the photocurrent of the device and verify the GeSn MSM photodetector has a mid-IR photoresponse at wavelength of 2 μm.

[1] S. Gupta, R. Chen, B. Magyari-Kope, H. Lin, Y. Bin, A. Nainani, et al., "GeSn technology: Extending the Ge electronics roadmap," in Electron Devices Meeting (IEDM), 2011 IEEE International, 2011, pp. 16.6.1-16.6.4.
[2] Bruce Booth et al. (2013), "On-board optical interconnection", CTR III TEG Report, MIT Microphotonics Center.
[3] Koester, S. J., et al. (2007), "Ge-on-SOI-Detector/Si-CMOS-Amplifier Receivers for High-Performance Optical-Communication Applications." Lightwave Technology, Journal of 25(1): 46-57.
[4] A. Kah-Wee, L. Tsung-Yang, Y. Ming-Bin, F. Qing, S. Junfeng, L. Guo-Qiang, et al., "Low Thermal Budget Monolithic Integration of Evanescent-Coupled Ge-on-SOI Photodetector on Si CMOS Platform," Selected Topics in Quantum Electronics, IEEE Journal of, vol. 16, pp. 106-113, 2010.
[5] R. Braunstein, A. R. Moore, and F. Herman, "Intrinsic Optical Absorption in Germanium-Silicon Alloys," Physical Review, vol. 109, pp. 695-710, 02/01/ 1958.
[6] Jerome Faist, "Optical properties of semiconductors," Eidgenossische Technische Hochshule Zurich, 2008.
[7] Dyan Ali, "Silicon-Germanium Photodetectors for Optical Telecommunications," University of Maryland, College Park, 2012.
[8] K. Hammani, M. A. Ettabib, A. Bogris, A. Kapsalis, D. Syvridis, M. Brun, et al., "Optical properties of silicon germanium waveguides at telecommunication wavelengths," Optics Express, vol. 21, pp. 16690-16701, 2013/07/15 2013.
[9] Y. Kim, M. Yokoyama, N. Taoka, M. Takenaka, and S. Takagi, "Ge-rich SiGe-on-insulator for waveguide optical modulator application fabricated by Ge condensation and SiGe regrowth," Optics Express, vol. 21, pp. 19615-19623, 2013/08/26 2013.
[10] WirthsS, GeigerR, N. von den Driesch, MusslerG, StoicaT, MantlS, et al., "Lasing in direct-bandgap GeSn alloy grown on Si," Nat Photon, vol. 9, pp. 88-92, 02//print 2015.
[11] H.-Y. S. Koh, S.-L. Chen, P. B. Griffin, and J. D. Plummer, "High Quality Single-Crystal Laterally Graded SiGe on Insulator by Rapid Melt Growth," Electrochemical and Solid-State Letters, vol. 13, pp. H281-H283, August 1, 2010 2010.
[12] S. Assefa, S. Shank, W. Green, M. Khater, E. Kiewra, C. Reinholm, et al., "A 90nm CMOS integrated Nano-Photonics technology for 25Gbps WDM optical communications applications," in Electron Devices Meeting (IEDM), 2012 IEEE International, 2012, pp. 33.8.1-33.8.3.
[13] S. Gupta, "GERMANIUM-TIN (GESN) TECHNOLOGY," STANFORD UNIVERSITY, 2013.
[14] D. Nam, D. Sukhdeo, A. Roy, K. Balram, S.-L. Cheng, K. C.-Y. Huang, et al., "Strained germanium thin film membrane on silicon substrate for optoelectronics," Optics Express, vol. 19, pp. 25866-25872, 2011/12/19 2011.
[15] G. Capellini, G. Kozlowski, Y. Yamamoto, M. Lisker, C. Wenger, G. Niu, et al., "Strain analysis in SiN/Ge microstructures obtained via Si-complementary metal oxide semiconductor compatible approach," Journal of Applied Physics, vol. 113, p. 013513, 2013.
[16] J. R. Jain, A. Hryciw, T. M. Baer, A. B. MillerDavid, M. L. Brongersma, and R. T. Howe, "A micromachining-based technology for enhancing germanium light emission via tensile strain," Nat Photon, vol. 6, pp. 398-405, 06//print 2012.
[17] Y. Huo, H. Lin, R. Chen, M. Makarova, Y. Rong, M. Li, et al., "Strong enhancement of direct transition photoluminescence with highly tensile-strained Ge grown by molecular beam epitaxy," Applied Physics Letters, vol. 98, p. 011111, 2011.
[18] R. Ragan and H. A. Atwater, "Measurement of the direct energy gap of coherently strained SnxGe1−x/Ge(001) heterostructures," Applied Physics Letters, vol. 77, pp. 3418-3420, 2000.
[19] Y.-H. Peng, H. H. Cheng, V. I. Mashanov, and G.-E. Chang, "GeSn p-i-n waveguide photodetectors on silicon substrates," Applied Physics Letters, vol. 105, p. 231109, 2014.
[20] Y. Liu, M. D. Deal, and J. D. Plummer, "High-quality single-crystal Ge on insulator by liquid-phase epitaxy on Si substrates," Applied Physics Letters, vol. 84, pp. 2563-2565, 2004.
[21] M. Kurosawa, Y. Tojo, R. Matsumura, T. Sadoh, and M. Miyao, "Single-crystalline laterally graded GeSn on insulator structures by segregation controlled rapid-melting growth," Applied Physics Letters, vol. 101, p. 091905, 2012.
[22] J. Wen, Z. Liu, L. Li, C. Li, C. Xue, Y. Zuo, et al., "Room temperature photoluminescence of Ge-on-insulator structures formed by rapid melt growth," Journal of Applied Physics, vol. 113, p. 143107, 2013.
[23] Shu-Lu Chen, "Design and Process for Three-Dimensional Heterogeneous Integration," the Department of Electrical Engineering and the Committee on Graduate Studies of Stanford University, 2010.
[24] T. Chih-Kuo, C. Ching-Hsiang, Y. Shih-Che, H. Kuang-Chien, N. Neil, and L. Ming-Chang, "GeSn waveguide photodetectors fabricated by rapid-melt-growth method," in Next-Generation Electronics (ISNE), 2015 International Symposium on, 2015, pp. 1-4.
[25] R. W. Olesinski and G. J. Abbaschian, "The Ge−Sn (Germanium−Tin) system," Bulletin of Alloy Phase Diagrams, vol. 5, pp. 265-271, 1984/06/01 1984.
[26] R. W. Olesinski and G. J. Abbaschian, "The Ge−Si (Germanium-Silicon) system," Bulletin of Alloy Phase Diagrams, vol. 5, pp. 180-183, 1984/04/01 1984.
[27] R. W. Olesinski and G. J. Abbaschian, "The Si−Sn (Silicon−Tin) system," Bulletin of Alloy Phase Diagrams, vol. 5, pp. 273-276, 1984/06/01 1984.
[28] E. Scheil, "Bemerkungen zur schichtkristallbildung," Zeitschrift für Metallkunde, vol. 34, pp. 70-72, 1942.
[29] J.D. Plummer, M.D. Deal, P.B. Griffin, "Silicon VLSI Technology – Fundamentals, Practice and Modeling", Prentice Hall, 2000.
[30] M. Xiong and A. V. Kuznetsov, "Comparison between Lever and Scheil Rules for Modeling of Microporosity Formation during Solidification," Flow, Turbulence and Combustion, vol. 67, pp. 305-323, 2001/12/01 2001.
[31] J. Liu, Photonic Devices: Cambridge University Press, 2005.
[32] M. Klingenstein, J. Kuhl, J. Rosenzweig, C. Moglestue, A. Hülsmann, J. Schneider, et al., "Photocurrent gain mechanisms in metal-semiconductor-metalphotodetectors," Solid-State Electronics, vol. 37, pp. 333-340, 2// 1994.
[33] J. D. Hwang and E. H. Zhang, "Effects of a a-Si:H layer on reducing the dark current of 1310 nm metal–germanium–metal photodetectors," Thin Solid Films, vol. 519, pp. 3819-3821, 3/31/ 2011.
[34] R. Matsumura, Y. Kai, H. Chikita, T. Sadoh, and M. Miyao, "Formation of Large Grain Ge Single Crystal on Insulating Substrate by Liquid-Solid Coexisting Annealing of a-Ge(Sn)," ECS Transactions, vol. 61, pp. 97-100, March 26, 2014 2014.
[35] J. Liu, "Monolithically Integrated Ge-on-Si Active Photonics," Photonics, vol. 1, p. 162, 2014.
[36] C. Wei-Ting, T. Chih-Kuo, C. Ku-Hung, L. Han-Din, K. Yimin, N. Na, et al., "Self-Aligned Microbonded Germanium Metal-Semiconductor-Metal Photodetectors Butt-Coupled to Si Waveguides," Selected Topics in Quantum Electronics, IEEE Journal of, vol. 20, pp. 17-21, 2014.
[37] F. Pezzoli, E. Bonera, E. Grilli, M. Guzzi, S. Sanguinetti, D. Chrastina, et al., "Raman spectroscopy determination of composition and strain in heterostructures," Materials Science in Semiconductor Processing, vol. 11, pp. 279-284, 10// 2008.
[38] M. Abidin, T. Morshed, H. Chikita, Y. Kinoshita, S. Muta, M. Anisuzzaman, et al., "The Effects of Annealing Temperatures on Composition and Strain in SixGe1−x Obtained by Melting Growth of Electrodeposited Ge on Si (100)," Materials, vol. 7, p. 1409, 2014.
[39] M. Miyao, T. Tanaka, K. Toko, and M. Tanaka, "Giant Ge-on-Insulator Formation by Si-Ge Mixing-Triggered Liquid-Phase Epitaxy," Applied Physics Express, vol. 2, Apr 2009.
[40] S. J. Park, K. H. Kim, W. S. Sohn, J. H. Oh, J. Jang, S. H. Kang, et al., "Investigation of Micro-Structural Change Using Raman Spectroscopy During Ni Silicide Mediated Crystallization of Amorphous Silicon," Journal of the Korean Physical Society, vol. 42, pp. S466-471, 2003.
[41] D. Kosemura, A. Ogura, K. Usuda, and M. Tomita, Stress Measurements in Si and SiGe by Liquid-Immersion Raman Spectroscopy: INTECH Open Access Publisher, 2012.
[42] M. Oehme, M. Schmid, M. Kaschel, M. Gollhofer, D. Widmann, E. Kasper, et al., "GeSn p-i-n detectors integrated on Si with up to 4% Sn," Applied Physics Letters, vol. 101, p. 141110, 2012.
[43] C. G. Littlejohns, M. Nedeljkovic, C. F. Mallinson, J. F. Watts, G. Z. Mashanovich, G. T. Reed, et al., "Next Generation Device Grade Silicon-Germanium on Insulator," Scientific Reports, vol. 5, p. 8288, 02/06/online 2015.
[44] Y. Bogumilowicz, J.-P. Barnes, P. Holliger, D. Rouchon, N. Daval, J.-M. Hartmann, et al., "Ge Diffusion in Strained Si / Relaxed SiGe Heterostrucutures," ECS Transactions, vol. 3, pp. 1099-1108, October 20, 2006.
[45] T. Takanori, T. Kaoru, S. Taizoh, and M. Masanobu, "High Quality Single-Crystalline Ge-Rich SiGe on Insulator Structures by Si-Doping Controlled Rapid Melting Growth," Applied Physics Express, vol. 3, p. 031301, 2010.