本論文成功利用熱燈絲化學氣相沉積法 (Hot Filament Chemical Vapor Deposition) ，成長氧化鎳奈米結構並研究在不同基板下成長各氧化鎳的奈米結構薄膜及進行其結構與光學特性分析。藉由X-ray晶格繞射 (X-ray diffraction, XRD) ，拉曼光譜儀 (Raman spectroscopy) 分析可得氧化鎳奈米晶體為立方體系結構 (Cubic structure) ，使用場發射掃描式電子顯微鏡 (Field-Emission Scanning Electron Microscope, FESEM) 觀察得知氧化鎳在相同成長條件之下沉積於不同的基板上，會呈現不同的型貌分別為奈米線和奈米立方結構，由FESEM外觀上檢視可以推論長在藍寶石基板上的薄膜結構品質較佳。
藉由溫度相依光激發螢光光譜的實驗，可以觀察到激子發光的相關訊號，分別為自由激子態 (Free exciton, FX) 以及束縛激子複合態 (Bound exciton complexs, BECs) ，另外利用在10 K下進行功率相依的PL實驗來驗證施子-受子對 (Donor-Acceptor Pair, DAP) 的發光訊號。
在光學量測上，藉由熱調制及穿透實驗觀察出此材料為直接能隙半導體，在300 K之躍遷訊號分別為A=3.27 eV與B=3.55 eV，同時經由與光激發螢光實驗結果交叉比對，得知在A=3.27 eV之訊號為激子躍遷 (Exciton) ，最後利用溫度相依之熱調制光譜實驗來觀察氧化鎳近能隙及激子躍遷能量-溫度變化關係。基於以上的光學實驗結果，氧化鎳奈米結構之近能隙光學特性得以被了解。

NiO thin-film nanostructures were grown by hot filament chemical vapor deposition method on different substrates. X-ray diffraction and Raman spectroscopy confirmed cubic structure for the nickel oxide nanostructures. Field emission scanning electron microscope (FESEM) images revealed different structural morphology for different substrate samples owing to different substrate orientations (i.e. nanowires for Si and nanocubes for sapphire substrate) .
Optical properties of near-band-edge emissions of NiO film deposited on sapphire are characterized using photoluminescence (PL) measurements in the temperature range between 10 and 300 K. Free exciton (FX) and bound exciton complexes (BECs) have been observed at low temperatures. Emission features originated from donor-acceptor pair (DAP) have also been determined using power dependent PL spectroscopy at 10 K.
The near-band-edge transitions of NiO were characterized experimentally by thermoreflectance (TR) and transmission measurements. The experimental results showed that NiO is a direct semiconductor with band-edge transitions of A=3.27 eV and B=3.55 eV at 300 K, respectively. In comparison with the PL and TR measurements, the transition of A=3.27 eV is inferred to be an excitonic transition near band edge. On the basis of experimental results, the optical properties of NiO nanostructures have thus been realized.

[1] L. Wu, Y. Wu, H. Wei, Y. Shi, and C. Hu, "Synthesis and characteristics of NiO nanowire by a solution method," Materials Letters, vol. 58, pp. 2700-2703, 2004.
[2] A. Manikandan, J. J. Vijaya, and L. J. Kennedy, "Comparative investigation of NiO nano- and microstructures for structural, optical and magnetic properties," Physica E, vol. 49, pp. 117-123, 2013.
[3] R. S. Devan, R. A. Patil, J. H. Lin, and Y. R. Ma, "One-Dimensional Metal-Oxide Nanostructures: Recent Developments in Synthesis, Characterization, and Applications," Advanced Functional Materials, vol. 22, pp. 3326–3370, 2012.
[4] B. Subramanian, M. M. Ibrahim, V. Senthilkumar, K. R. Murali, V. S. Vidhya, C. Sanjeeviraja, et al., "Optoelectronic and electrochemical properties of nickel oxide (NiO) films deposited by DC reactive magnetron sputtering," Physica B, vol. 403, pp. 4104-4110, 2008.
[5] S. Chakrabarty and K. Chatterjee, "Synthesis and Characterization of Nano-Dimensional Nickelous Oxide (NiO) Semiconductor," Journal of Physical Sciences, vol. 13, pp. 245-250, 2009.
[6] E. Fujii, A. Tomozawa, H. Torii, and R. Takayama, "Preferred orientations of NiO films prepared by plasma-enhanced metalorganic chemical vapor deposition," Japanese Journal of Applied Physics, vol. 35, pp. 328-330, 1996.
[7] K. Yoshimura, T. Miki, and S. Tanemura, "Nickel oxide electrochromic thin films prepared by reactive dc magnetron sputtering," Japanese Journal of Applied Physics, vol. 34, pp. 2440-2446, 1995.
[8] M. Bogner, A. Fuchs, K. Scharnagl, R. Winter, T. Doll, and I. Eisele, "Thin (NiO)1-x(Al2O3)x, Al doped and Al coated NiO layers for gas detection with HSGFET," Sensors and Actuators B: Chemical, vol. 47, pp. 145-152, 1998.
[9] I. M. Chan and F. C. Hong, "Improve performance of the single-layer and double-layer organic light emitting diodes by nickel oxide coated indium tin oxide anode," Thin Solid Films, vol. 450, pp. 304-311, 2004.
[10] H. Ohta and H. Hosono, "Transparent oxide optoelectronics," Materials Today, vol. 7, pp. 42-51, 2004.
[11] Y. Shimizu, T. Yamashita, and S. Takase, "Electrirochromic phosphate-ion sensor based on nickel-oxide thin film electrode," Journal of Applied Physics, vol. 39, pp. 384-386, 2000.
[12] Q. X. Xia, K. S. Hui, K. N. Hui, D. H. Hwang, S. K. Lee, W. Zhou, et al., "A facile synthesis method of hierarchically porous NiO nanosheets," Materials Letters, vol. 69, pp. 69-71, 2012.
[13] M. J. Lee, Y. Park, S. E. Ahn, B. S. Kang, C. B. Lee, K. H. Kim, et al., "Comparative structural and electrical analysis of NiO and Ti doped NiO as materials for resistance random access memory," Journal of Applied Physics, vol. 103, pp. 013706 - 013706-4, 2008.
[14] K. K. Purushothaman and G. Muralidharan, "The effect of annealing temperature on the electrochromic properties of nanostructured NiO films," Solar Energy Materials & Solar Cells, vol. 93, pp. 1195-1201, 2009.
[15] V. Patil, S. Pawar, M. Chougule, P. Godse, R. Sakhare, S. Sen, et al., "Effect of Annealing on Structural, Morphological, Electrical and Optical Studies of Nickel Oxide Thin Films," Journal of Surface Engineered Materials and Advanced Technology, vol. 1, pp. 35-41, 2011.
[16] Y. Lin, T. Xie, B. Cheng, B. Geng, and L. Zhang, "Ordered nickel oxide nanowire arrays and their optical absorption properties," Chemical Physics Letters, vol. 380, pp. 521-525, 2003.
[17] D. Y. Jiang, J. M. Qin, X. Wang, S. Gao, Q. C. Liang, and J. X. Zhao, "Optical properties of NiO thin films fabricated by electron beam evaporation," Vacuum, vol. 86, pp. 1083-1086, 2012.
[18] I. Hotovy, J. Huran, and L. Spiess, "Characterization of sputtered NiO films using XRD and AFM " Journal of Materials Science Letters, vol. 39, pp. 2609-2612, 2004.
[19] R. P. Rastogi, N. B. Singh, and S. K. Shukla, "Synthesis of NiO nano crystals through nitrate eutectic melt," Indian Journal of Engineering & Materials Sciences, vol. 17, pp. 477-480, 2010.
[20] W. Wang, Y. Liu, C. Xu, C. Zheng, and G. Wang, "Synthesis of NiO nanorods by a novel simple precursor thermal decomposition approach," Chemical Physics Letters, vol. 362, pp. 119-122, 2002.
[21] J. T. Richardson, R. M. Scates, and M. V. Twigg, "X-ray diffraction study of the hydrogen reduction of NiO/-Al2O3 steam reforming catalysts " Applied Catalysis, vol. 267, pp. 35-46, 2004.
[22] L. Courtade, C. Turquat, C. Muller, J. G. Lisoni, L. Goux, D. J. Wouters, et al., "Oxidation kinetics of Ni metallic films: Formation of NiO-based resistive switching structures," Thin Solid Films, vol. 516, pp. 4083-4092, 2008.
[23] N. M. Ulmane, A. Kuzmin, I. Steins, J. Grabis, I. Sildos, and M. Pars, "Raman scattering in nanosized nickel oxide NiO," Journal of Physics: Conference Series, vol. 93, pp. 012-039, 2007.
[24] M. Kadleı́kova, J. Breza, and M. Vesely, "Raman spectra of synthetic sapphire," Microelectronics Journal, vol. 32, pp. 955-958, 12// 2001.
[25] S. H. Lee, H. M. Cheong, N. G. Park, C. E. Tracy, A. Mascarenhas, D. K. Benson, et al., "Raman spectroscopic studies of Ni–W oxide thin films," Solid State Ionics, vol. 140, pp. 135-139, 2001.
[26] M. Magnuson, S. M. Butorin, A. Agui, and J. Nordgren, "Resonant soft X-ray Raman scattering of NiO," Journal of Physics: Condensed Matter, vol. 14, pp. 3669-3676, 2002.
[27] E. F. Funkenbusch and B. C. Cornilsen, "Two-magnon raman scattering in calcium doped NiO," Solid State Communications, vol. 40, pp. 707-710, 1981.
[28] B. O. Seraphin, The effect of an electric field on reflectivivty of germannium. Proc. 7th int. Conf. Phys. Semicond, Academic, Dunod, 1964.
[29] M. Cardona, In Modulation Spectroscopy. Academic press, New York, 1969.
[30] D. E. Aspnes Modulation Spectroscopy/Electric Field Effects on the Dielectric Function of Semiconductors in Handbook on Semiconductors. Vol.2, ed. By M. Balkanski, North HollandPublishing Co, Amsterdam, pp.109-154, 1980.
[31] A. K. Berry, D. K. Gaskill, G. T. Stauf, and N. Bottka, "Photoreflectance of semi-insulating InP: Resistivity effects on the exciton phase," Applied Physics Letters, vol. 58, pp. 2824-2827, 1991.
[32] S. E. Acosta-Ortiz and A. Lastras-Martinez, "Electro-optic effects in the optical anisotropies of (001) GaAs," Physical Review B, vol. 40, pp. 1426-1429, 1989.
[33] P. Lorrain and D. R. Corson, "Electromagnetic Fields and Wave. J Yuan Publishing CO. Taipei, Taiwan, pp.508-511, 1972.
[34] Z. Y. Wu, C. M. Liu, L. Guo, R. Hu, M. I. Abbas, T. D. Hu, et al., "Structural Characterization of Nickel Oxide Nanowires by X-ray Absorption Near-Edge Structure Spectroscopy," Journal of Physical Chemistry B, vol. 109, pp. 2512-2515, 2005.
[35] X. T. Zu, S. Zhu, X. Xiang, and L. M. Wang, "TEM and Optical Studies of Ni/NiO Nanoparticles in Ni-ion-implanted Al2O3," Microscopy and Microanalysis, vol. 11 pp. 1930-1931, 2005