本論文使用化學氣相傳導法合成層狀過渡金屬硫屬化物ReSe2，並且利用氧電漿摻雜的方式將其製作成同質接面pn二極體，將其應用於半波整流及光感測元件。利用拉曼光譜儀分析其晶格振動模態之變化，並分別以X光能量散佈分析儀、X光繞射分析儀與X光光電子能譜儀檢測其在摻雜前後的變化。首先將合成完畢之ReSe2以膠帶利用機械剝離法的方式控制其厚度，再利用電漿輔助化學氣相沉積系統進行氧電漿摻雜，摻雜完畢後進行電荷中性點量測，確認ReSe2在摻雜過後半導體特性的變化，發現在摻雜功率50 W時將ReSe2從n型半導體轉變成p型半導體，另外拉曼光譜圖也可以看出在40 W開始出現ReO3之訊號，X光能量散佈分析與X光光電子能譜圖證明氧原子確實有摻雜進樣品內，X光繞射分析圖可以看出摻雜前後角度上的偏移，證明氧摻雜改變其晶格。以電性量測確認pn特性曲線，利用pn二極體單向導通的特性應用於半波整流上，施加頻率1 Hz至20 kHz之正弦波，發現在頻率1 kHz內有不錯的整流效果。接著以532 nm雷射量測其光學特性，探討摻雜前後光電導率與光響應度對雷射功率的關係，發現經過氧電漿摻雜成同質接面pn二極體後可以得到較好的光電流值，並且呈現出光伏特效應，主要原因是經過摻雜後可以改變接面的位障，以及增加表面缺陷與陷阱態，進而提升光感測效益，由此結果可以利用氧電漿摻雜於ReSe2製成光感測器與其應用。

In this thesis, we used chemical vapor transport method to synthesize layered transition metal dichalcogenides ReSe2 single crystal, and fabricated homojunction pn diode through oxygen plasma treatment. Then we used homojunction pn diode to conduct half wave rectify experiment and made it into photodetector device. The lattice vibration of ReSe2 was demonstrated by Raman spectroscopy. The composition difference of ReSe2 before and after oxygen plasma treatment was investigated by Energy dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). The crystal structure of ReSe2 was confirmed by X-ray diffraction (XRD). We exfoliated ReSe2 single crystal and controlled it thickness. Then we used plasma enhanced chemical vapor deposition system to conduct oxygen plasma treatment. Central neutral point experiment was conducted to investigate semiconductor type change of ReSe2. The result showed that ReSe2 changed from n-type semiconductor to p-type semiconductor after 50 W oxygen plasma treatment. Raman spectra demonstrated vibration mode of ReO3 started from 40 W oxygen plasma treatment. EDX and XPS proved oxygen atoms truely doped into ReSe2 sample. We found peak shifts from XRD pattern, proving oxygen plasma changed ReSe2 crystal structure. Based on unidirectional behavior of pn diode, we tested rectified property at different frequency from 1 Hz to 20 kHz. It showed well results below 1 kHz frequency. We fabricated ReSe2 into photodetector and demonstrated photocurrent properties and photovoltaic properties under 532 nm laser. The better optoelectronic characteristics after oxygen plasma treatment due to difference of junction barrier and create more surface defects. From the results, we inferred that ReSe2 provides an application on rectifier and photodetector after oxygen plasma treatment.

[1] F.Bonaccorso, Z. Sun, T. Hasan, and A. C. Ferrari, “Graphene photonics and optoelectronics,” Nature Photon., vol. 4, pp. 611-622, 2010.
[2] X. Li, Y. Zhu, W. Cai, M. Borysiak, B. Han, D. Chen, R. D. Piner, L. Colomba, and R. S. Ruoff, “Transfer of large-area graphene films for high-performance transparent conductive electrodes,” Nano Lett., vol. 9, pp. 4359-4363, 2009.
[3] F. Schwierz, “Graphene transistors,” Nature Nanotech., vol. 5, pp.487-496, 2010.
[4] K. I. Bolotin, K. J. Sikes, Z. Jiang, M. Klima, G. Fudenberg, J. Hone, P. Kim, and H. L. Stormer, “Ultrahigh electron mobility in suspended graphene,” Solid State Commun., vol. 146, pp.351-355, 2008.
[5] Y. Zhu, S. Murali, W. Cai, X. Li, J. W. Suk, J. R. Potts, and R. S. Ruoff, “Graphene and graphene oxide: synthesis, properties, and applications,” Adv. Mater., vol. 22, pp. 3906-3924, 2010.
[6] D. Wei, Y. Liu, Y. Wang, H. Zhang, L. Huang, and G. Yu, “Synthesis of n-doped graphene by chemical vapor deposition and its electrical properties,” Nano Lett., vol. 9, pp. 1752-1758, 2009.
[7] W. J. Yu, Y. Liu, H. Zhou, A. Lin, Z. Li, Y. Huang, and X. Duan, “Highly efficient gate-tunable photocurrent generation in vertical heterostructures of layered materials,” Nature Nanotech., vol. 8, pp. 952-958, 2013.
[8] W. Jaegermann and H. Tributsch, “Interfacial properties of semiconducting transition metal chalcogenides,” Progress Surf. Sci., vol. 29, pp. 1-167, 1988.
[9] H. Li, J. Wu, Z. Yin, and H. Zhang, “Preparation and applications of mechanically exfoliated single-layer and multilayer MoS2 and WSe2 nanosheets,” Acc. Chem. Res., vol. 47, pp. 1067-1075, 2014.
[10] A. Splendiani, L. Sun, Y. Zhang, T. Li, J. Kim, C. Y. Chim, G. Galli, and F. Wang, “Emerging photoluminescence in monolayer MoS2,” Nano Lett., vol. 10, pp. 1271-1275, 2010.
[11] G. A. N. Connell, J. A. Wilson, and A. D. Yoppe, “Effects of pressure and temperature on exciton absorption and band structure of layer crystals: Molybdenum disulphide,” J.Phy. Chem. Solids, vol. 30, pp. 287-296, 1969.
[12] W. J. Schutte, J. L. D. Boer, and F. Jellinek, “Crystal structures of tungsten disulfide and diselenide,” J. Solid State Chem., vol. 70, pp. 207-209, 1987.
[13] R. Tenne, and M. Redlich, “Recent progress in the research of inorganic fullerene-like nanoparticles and inorganic nanotubes,” Chem. Soc. Rev., vol. 39, pp. 1423-1434, 2010.
[14] A. Kuc and T. Heine, ”The Electronic Structure Calculations of Two-Dimensional Transition-Metal Dichalcogenides in the Presence of External Electric and Magnetic Fields,” Chem. Soc. Rev., vol. 44, pp.2603-2614, 2015.
[15] H. J. Lamfers, A. Meetsma. G. A. Wiegers, and J. L. de Boer, “The crystal structure of some rhenium and technetium dichalcogenides,” J. Alloys Compd., vol. 241, pp. 34-39, 1996.
[16] C. H. Ho, “Optical study of the structural change in ReS2 single crystals using polarized thermoreflectance spectroscopy,” Opt. Express., vol. 13, pp. 8-19, 2005.
[17] S. Yang, S. Tongay, Q. Yue, Y. Li, B. Li, and F. Lu, “High-performance few-layer Mo-doped ReSe2 nanosheet photodetectors,” Sci. Rep., vol. 4, pp. 5442, 2014.
[18] H. Zhao, J. Wu, H. Zhong, Q. Guo, X. Wang, F. Xia, L. Yang, P. Tan, and H. Wang, “Interlayer interactions in anisotropic atomically thin rhenium diselenide,” Nano. Research, vol. 8, pp. 3651-3661, 2015.
[19] B. L. Wheeler, J. K. Leland, and A. J. Bard, “Semiconductor electrodes LX. photoelectrochemistry of p-rhenium disulfide and p-rhenium diselenide in aqueous solutions,” J. Electrochem. Soc., vol. 133, pp. 358-361, 1986.
[20] S. Yang, S. Tongay, Y. Li, Q. Yue, J. B. Xia, S. S. Li, J. Li, and S. H. Wei, “Layer-dependent electrical and optoelectronic responses of ReSe2 nanosheet transistors,” Nanoscale, vol. 6, pp. 7226-7231, 2014.
[21] C. Wang, S. Yang, W. Xiong, C. Xia, H. Cai, B. Chen, X. Wang, X. Zhang, Z. Wei, and S. Tongay, “Gate-tunable diode-like current rectification and ambipolar transport in multilayer van der Waals ReSe2/WS2 p–n heterojunctions,” Phys. Chem. Chem. Phys., vol. 18, pp. 27750-27753, 2016.
[22] A. J. Waldu, M. C. L. Steiner, G. J. Waldu, and E. Bucher, “WS2 thin films prepared by sulphurization,” Appl. Surf. Sci., vol. 70-71, pp. 731-736, 1993.
[23] L. M. Xie, “Two-dimensional transition metal dichalcongenide alloys: preparation, characterization and applications,” Nanoscale, vol. 7, pp. 18392-18401, 2015.
[24] A. K. Rai, R. S. Bhattacharya, J. S. Zabinski, and K. Miyoshi, “A comparison of the wear life of as-deposited and ion-irradiated WS2 coating,” Surf. Coat. Technol., vol. 92, pp. 120-128, 1997.
[25] R. Lv, J. A. Robinson, R. E. Schaak, D. Sun, Y. Sun, T. E. Mallouk, and M. Terrones, “Transition metal dichalcogennides and beyond: synthesis, properties, and applications of single- and few- layer nanosheets,” Acc. Chem. Res., vol. 48, pp. 56-64, 2015.
[26] A. Ubaldini, J. Jacimovic, N. Ubrig, and E. Giannini, “Chloride-driven chemical vapor transport method for crystal growth of transition metal dichalcogennides,” Cryst. Growth Des., vol. 13, pp. 4453-4459, 2013.
[27] R. Vaidya, M. Dave, S. S. Patel, S. G. Patel, and A. R. Jani, “Growth of molybdenum disulfide using iodine as transport material,” Pramana., vol. 63, pp. 611-616, 2004.
[28] M. Binnewies, R. Glaum, M. Schmidt, and P. Schmidt, “Chemical vapor transport reactions – a historical review,” Z. Anorg. Allg. Chem., vol. 639, pp. 219-229, 2013.
[29] Q. H. Wang, K. K. Zadeh, A. Kis, J. S. Zabinski, and K. Miyoshi, “Electronics and optoelectronics of two-dimensional transition metal dichalcogenides,” Nature Nanotech., vol. 7, pp. 699-712, 2012.
[30] S. Sze, Semiconductor devices physics and technology. Toronto: John Wiley and Sons, 1995.
[31] W. Zhu, T. Low, Y. H. Lee, H. Wang, D. B. Farmer, J. Kong, F. Xia, and P. Avouris, “Electronic transport and device prospects of monolayer molybdenum disulphide grown by chemical vapor deposition,” Nat. Commun., vol. 5, pp. 3087-1-3087, 2014.
[32] M. M. Furchi, D. K. Polyushkin, A. Pospischil, and T. Mueller, “Mechanisms of photoconductivity in atomically thin MoS2,” Nano Lett., vol. 14, pp.6165-6170, 2014.
[33] R. S. Chen, T. H. Tang, H. Y. Chen, L. C. Chen, K. H. Chen, Y. J. Yang, C. H. Su, and C. R. Lin, “Photoconduction mechanism of oxygen sensitization in InN nanowires,” Nanotechnology, vol. 22, pp. 425702, 2011.
[34] A. Varghese, D. Saha, K. Thakar, V. Jindal, S. Ghosh, N. V. Medhekar, S. Ghosh, and S. Lodha, “Near-direct bandgap WSe2/ReS2 type-II pn heterojunction for enhanced ultrafast photodetection and high-performance photovoltaics,” Nano Lett, vol. 20, pp. 1707-1717, 2020.
[35] J. Dong and D. A. Drabold, “Atomistic structure of band-tail states in amorphous silicon,” Phys. Rev. Lett., vol. 80, pp.19728-1931, 1998.
[36] M. Buscema. J. O. Island, D. J. Groenendijk, S. I. Blanter, G. A. Steele, H. S. J. van der Zant, and A. C. Gomez, “Photocurrent generation with two-dimensional van der Waals semiconductors,” Chem. Soc. Rev., vol. 44, pp. 3691-3718, 2015.
[37] A. Politano and G. Chiarello, “Plasmon modes in Graphene: status and prospect” Nanoscale, vol. 6, pp. 10927-10940, 2014.
[38] Y. Zhang, Y. W. Tan, H. L. Stormer, and P. Kim, “Experimental observation of the quantum Hall effect and Berry’s phase in graphene,” Nature, vol. 438, pp. 201-204, 2005.
[39] K. S. Novoselov, Z. Jiang, Y.Zhang, S. V. Morozov, H. L. Stormer, U. Zeitler, J. C. Maan, G. S. Boebinger, P. Kim, and A. K. Geim, “Room-temperature quantum hall effect in graphene” Science, vol. 315, pp. 1379, 2009.
[40] F. Schedin, A. K. Geim, S. V. Morozov, E. W. Hill, P. Blake, M. I. Katsnelson, and K. S. Novoselov, “Detection of individual gas molecules absorbed on graphene,” Nature Mater., vol. 6, pp. 652-655, 2007.
[41] S. Yang, C. Wang, H. Sahin, H. Chen, Y. Li, S. S. Li, A. Suslu, F. M. Peeters, Q. Liu, J. Li, and S. Tongay, “Tuning the optical , magnetic, and electrical properties of ReSe2 by nanoscale strain engineering,” Nano Lett., vol. 15, pp. 1660-1666, 2015.
[42] S. H. Jo, H. Y. Park, D. H. Kang, J. Shim, J. Jeon, S. Choi, M. Kim, Y. Park, J. Lee, Y. J. Song, S. Lee, and J. H. Park, “Broad detection range rhenium diselenide photodetector enhanced by (3-aminopropyl) triethoxysilane and triphenylphosphine treatment,” Adv. Mater., vol. 28, pp. 6711-6718, 2016.
[43] M. Binnewies, R. Glaum, M. Schmidt, and P. Schnidt, “Chemical vapor transport method for crystal growth of transition metal dichalcogenidies,” Cryst. Growth Des., vol. 13, 4453-4459, 2013.
[44] D. Wolverson, S. Crampin, A. S. Kazemi, A. Ilie, and S. J. Bending, ”Raman spectra of monolayer, few-layer, and bulk ReSe2: An isotropic layered semiconductor,” ACS. Nano., vol. 8, pp. 11154-11164, 2014.
[45] J. Purans, A. Kuzmin, A. Cazzanelli, and G. Mariotto, “Disorder-induced Raman scattering in rhenium trioxide (ReO3),” J. Phys: Condens. Matter, vol. 19, pp. 226206, 2007.
[46] B. Jariwala, D. Voiry, A. Jinda, B. A Chalke, R. Bapat, A. Thamizhavel, M. Chhowalla, M. Deshmukh, and Bhattacharya, “Synthesis and characterization of ReS2 and ReSe2 layered chalcogenide single crystals,” Chemistry of Materials, vol. 28, pp. 3352-3359, 2016.
[47] M. R. Islam, N. Kang, U. Bhanu, H. P. Paudel, M. Erementchouk, L. Tetard, M. N. Leuenberger, and S. I. Khondaker, “Tunning the electrical property via defect engineering of single layer MoS2 by oxygen plasma,” Nanoscale, vol.6, pp.10033-10039, 2011.
[48] N. Kang, H. P. Paudel, M. N. Leuenberger, L. Tetard, and S. I. Khondaker, “Photoluminescence Quenching in Single-Layer MoS2 via Oxygen Plasma Treatment,” J. Phys. Chem. C, vol. 118, pp. 21258-21263, 2014.
[49] J. Shim, A. Oh, D. H. Kang, S. Oh, S. K. Jang, J. Jeon, M. H. Jeon, M. Kim, C. Choi, J. Lee, S. Lee, G. Y. Yeom, Y. J. Song, and J. H. Park, “High performance 2D rhenium disulfide (ReS2) transistors and photodetectors by oxygen plasma treatment,” Adv. Mater., vol. 28, pp. 6985-6992, 2016.
[50] M. Chhowalla, D. Jena, and H. Zhang, “Two-dimensional semiconductors for transistors,” Nature Reviews Materials, vol. 1, pp. 16052, 2016.
[51] J. R. D. Retamal, D. Periyanagounder, J. J. Ke, M. L. Tsai, and J. H. He, “Charge carrier injection and transport engineering in two-dimensional transition metal dichalcogendies,” Chem. Sci, vol. 9 , pp. 7727-7745, 2018.
[52] M. Liao, B. Shen, and Z. Wang, “Ultra-wide bandgap semiconductor materials,” pp. 1-503, 2019.
[53] G. L. Malli, “Relativistic and electron correlation effects in molecules and solids,” pp. 1-478, 1994.
[54] D. S. Leem, H. D. Park, J. W. Kang, J. H. Lee, J. W. Kim, and J. J. Kim, “Low driving voltage and high stability organic light-emitting diodes with rhenium oxide-doped hole transport layer,” Appl. Phys. Lett., vol. 91, pp. 011113, 2017.
[55] K. C. Lee, S. H. Yang, Y. S. Sung, Y. M. Chang, C. Y. Lin, F. S. Yang, M. Li, K. Watanabe, T. Taniguchi, C. H. Ho, C. H. Lien, and Y. F. Lin, “Analog circuit applications based on all-2D ambipolar ReSe2 field effect transistors,” Adv. Funct. Mater., vol. 29, pp. 1809011, 2019.
[56] Pankove, J. I., “Optical in semiconductors,” Dover, pp. 34-38, 1975.
[57] E. Zhang, P. Wang, Z. Li, H. Wang, C. Song, C. Huang, Z. G. Chen, L. Yang, K. Zhang, S. Lu, W. Wang, S. Liu, H. Fang, X. Zhou, H. Yan, J. Zou, X. Wan, P. Zhou, W. Hu, and F. Xiu, “Tunable ambipolar polarization-sensitive photodetectors based on high-anisotropy ReSe2 nanosheets,” ACS Nano, vol. 10, pp. 8067-8077, 2016.
[58] Y. J. Liu, C. Liu, X. M. Wang, L. He, X. G. Wan, Y. B. Xu, Y. Shi, R. Zhang, and F. Q. Wang, “Photoresponsivity of an all-semimetal heterostructure based on graphene and WTe2,” Sci. Rep., vol. 8, pp. 12840, 2018.
[59] W. J. Zhang, M. H. Chiu, C. H. Chen, W. Chen, L. J. Li, and A. T. S. Wee, “Role of metal contacts in high-performance phototransistors based on WSe2 monolayers,” ACS. Nano, vol. 8, pp. 8653-8661, 2014.
[60] J. Mao, Y. Q. Yu, L. Wang, X. J. Zhang, Y. M. Wang, Z. B. Shao, and J. S. Jie, “Ultrafast broadband photodetector based on MoSe2/Silicon heterojunction with vertically standing layered structure using graphene as transparent electrode,” Adv. Sci., vol. 3 pp. 1600018, 2016.
[61] W. H. Wu, Q. Zhang, X. Zhou, L. Li, J. W. Su, F. K. Wang, and T. Y. Zhai, “Self-powered photovoltaic photodetector established on lateral monolayer MoS2-WS2 heterostructures,” Nano. Energy, vol. 51, pp. 45-53, 2018.