本研究分為兩個部分，第一部份探討石墨烯堆疊不同層數於矽奈米線基板結構之氨氣感測器，並進行物性和電性分析；第二部份探討雙層石墨烯/PSG-SiNWs/RTA複合奈米結構之氨氣感測器，並進行物性和電性分析。

本研究第一部份的重點是使用不同層數的石墨烯以及兩種後處理(氫電漿後處理、快速熱退火後處理)來處理石墨烯之氨氣感測器，研究發現使用快速熱退火後處理會使石墨烯表面雜質聚集或是去除，以及多層石墨烯可提升石墨烯品質，因為下層石墨烯缺陷會被之後轉移上來的石墨烯填補，以增強其氨氣感測特性，與石墨烯氨氣感測器(2.98%)比較，基於3Gr/SiNWs/RTA有著極高的響應特性(46.68%)。主要原因是透過快速熱退火後處理的高溫讓表面雜質去除以達到更多氧分子吸附以及更多的氧缺陷空位。

在第二部分中，利用了P2O5的磷氧化物來摻雜奈米線，之後再轉移雙層石墨烯於摻雜好的矽奈米線上，並研究其複合結構及其氨氣感測特性。在研究的過程中發現P2O5(2Gr/PSG20 min-SiNWs/RTA 1min)在反應時間(40.55s)與還原時間(40.22s)有著不錯的特性，再將此特性結合石墨烯的靈敏度，與摻雜PSG15/SiNWs的響應(1.85%)相比，2Gr/PSG 20min-SiNWs/RTA 2.5min的響應略有提升(2.07%)，以達到快速響應時間以及靈敏度的表現。

Room temperature gas sensor is important system to sense and control the working atmosphere also the air quality. Among several gas sensors, ammonia (NH3) sensing is important due to the uses of ammonia gas in many areas such as biological productions, cleaning industries, enrichers, explosives, biochemical industries, fire power plants and ecological safety. Remarkably, ammoinia gas sensor must be sensitive to gas exposure with concentrations of >1,000 ppm could lead to serious human safety issues. Hence, the necessity to detect and control NH3 gas has led to the numerous research and development of effective ammonia gas sensor.

In this context, we have fabricated the highly sensitive NH3 gas sensor by using silicon nanowire (SiNWs) hybrid structures. This study is divided into two parts. The first part focusses the synthesis of different graphene stacking layers transferred on the SiNWs. The second part discusses 2-layer Gr with PSG doping on SiNWs using rapid thermal annealing (RTA) (Gr/PSG-SiNWs/RTA) method. Physical, electrical and gas sensing analysis are used to study the performance synthesized Gr-SiNWs and Gr/PSG-SiNWs/RTA hybrid structure.

In the first section, different layers of Gr synthesized and performed two post-treatments process such as hydrogen plasma and RTA post-treatment to enhance the gas sensing performance of Gr-SiNWs. Markedly, the RTA post treatment on 3-layer Gr-SiNWs exhibits the excellent NH3 sensing response of 46.68%, which is excellently better than as prepared Gr (2.98%). The main reason of excellent sensing response of three layers Gr-SiNWs is that the high temperature due to the RTA that allows surface impurities to be removed to achieve more oxygen molecular adsorption and more oxygen (O2) defect vacancies. In the second part, PSG is used to dope with the SiNWs and subsequently 2-layer graphene is transferred on the PSG-SiNWs. It was observed that the P2O5 (2Gr/PSG20 min-SiNWs/RTA 1min) has excellent gas sensor characteristics such as good response time (40.55s) and recovery time (40.22s). The improved NH3 sensing properties attained due to the exceptional hybridization properties and surface O2 defects of Gr-SiNWs due to RTA technique and PSG doping.

[1]. ”微機電系統之介紹”台灣肥料股份有限公司
[2]. ”Ammonia”WIKIPEDIA
[3]. G. Ruess and F. Vogt. “Höchstlamellarer Kohlenstoff aus Graphitoxyhydroxyd. Monatshefte für Chemie”. 1948, 78 (3-4): 222–242.
[4]. Geim, A. K. and Novoselov, K. S.. Nature Materials. 2007, 6 (3): 183–191.
[5]. Scientific American. April 2008 [2009-05-05]. “bits of graphene are undoubtedly present in every pencil mark”
[6]. “石墨烯”維基百科
[7]. “功能型粉末:奈米銀”科技大觀園
[8]. “金屬氧化物氣體感測器”貿澤電子
[9]. 黃炳照,”固態電解質電化學氣體感測器”, Chemistry (The Chinese Chem.Soc., Taipei), 59, pp. 207-217, 2001.
[10]. C.sonics , A. D’Amico, P. Verardi, and E. Verona, 1998 IEEE Ultrasonics Symposium Proc., pp. 549-554, 1988.
[11]. A. D’Amico, A. Plama, and E. Verona, “Surface acoustic wave hydrogen sensor”, Sens. Acuatros, 3, pp. 31-39, 1982.
[12]. 張宏維,周鈺禎,蔡顯仁,徐慧萍,施正雄, “表面聲波氣體感測器之研製與應用”, Chemistry (The Chinese Chem. Soc., Taipei) December, pp. 487-498, 2007.
[13]. 石墨烯的結構、性質與應用https://read01.com/J6PLkB.html
[14]. 石墨烯與二維材料-微奈米科技研究中心-林志堅
[15]. A. K. Geim, K. S. Novoselov. "The rise of graphene", Nature Mater, 6, 183 (2007).
[16]. A. A. Balandin, S. Ghosh, W. Bao, I. Calizo, D. Teweldebrhan, F. Miao, C. N. Lau Superior thermal; "conductivity of single-layer graphene", Nano Lett, 8,902-907(2008).

[17]. K.I. Bolotin, K.J. Sikes, Z. Jiang, M. Klima, G. Fudenberg, J. Hone, P. Kim,
H.L. Stormer. "Ultrahigh electron mobility in suspended graphene", Solid State Commun, 146,351-355 (2008).
[18]. Keun Soo Kim, Yue Zhao, Houk Jang, Sang Yoon Lee, Jong Min Kim, Kwang S. Kim, Jong-Hyun Ahn, Philip Kim, Jae-Young Choi & Byung Hee Hong, "Large-scale pattern growth of graphene films for stretchable transparent electrodes", Nature 457, 706-710, (2009)
[19]. R. R. Nair, P. Blake, A. N. Grigorenko, K. S. Novoselov, T. J. Booth, T. Stauber, N. M. R. Peres, A. K. Geim, "Fine Structure Constant Defines Visual Transparency of Graphene", Science,: Vol. 320 no. 5881 p. 1308,( 2008)
[20]. B. C. Brodie et al., Philos. Trans. R. Soc. London, “On the atomic weight of graphite”, Journal Article 149 (1959) 249.
[21]. W.S Hummers, R.E Offeman, J. Am. Chem. Soc., “Preparation of Graphitic Oxide”, ACS Publications 80 (1958) 1339-1339.
[22]. Y. Xu et al., J. Am. Chem. Soc., “Flexible graphene films via the filtration of water-soluble noncovalent functionalized graphene sheets”, ACS Publications 130 (2008) 5856.
[23]. X. Li, G. Zhang, X. Bai, X. Sun, X. Wang, E. Wang, H. Dai. “Highly conducting graphene sheets and Langmuir-Blodgett films”. Nature Nanotech 3 (2008) 538-542.
[24]. Yu Zhang, Jiale Du, Shuai Tang, Pei Liu, Shaozhi Deng, Jun Chen, Ningsheng 00Xu . "Optimize the field emission character of a vertical few-layer graphene sheet by manipulating the morphology". Nanotechnology 23 015202 (6pp) (2012)
[25]. Introduction to Graphene
[26]. 趙健仰、王瑞琪、鄭家宜，「細矽奈米線驚奇大無限」，科學發展，第486期，2013
[27]. K. Q. Peng, Y. J. Yan, S. P. Gao, J. zhu, “Synthesis of Large-Area Silicon Nanowire Arrays via Self-Assembling Nanoelectrochemistry,” Advanced Materials, vol. 14, pp. 1164-1167, 2002.
[28]. K. Q. Peng, Y. J. Yan, S. P. Gao, and J. Zhu, “Dendrite-assisted growth of silicon nanowires in electroless metal deposition,” Advanced Functional Materials, vol. 13, pp. 127-132, Feb 2003.
[29]. K. Peng and J. Zhu, “Simultaneous gold deposition and formation of silicon nanowire arrays,” Journal of Electroanalytical Chemistry, vol. 558, pp. 35-39, 2003.
[30]. K. Peng and J. Zhu, “Morphological selection of electroless metal deposits on silicon in aqueous fluoride solution,” Electrochimica Acta, vol. 49, pp. 2563-2568, 2004.
[31]. K. Q. Peng, Z. P. Huang, and J. Zhu, “Fabrication of large-area silicon nanowire p-n junction diode arrays,” Advanced Materials, vol. 16, pp. 73-76, 2004.
[32]. K. Peng, Y. Wu, H. Fang, X. Zhong, Y. Xu, and J. Zhu, “Uniform, axial-orientation alignment of one-dimensional single-crystal silicon nanostructure arrays,” Angew Chem Int Ed Engl, vol. 44, pp. 2737-42, Apr 29 2005.
[33]. K. Peng, Y. Xu, Y. Wu, Y. Yan, S. T. Lee, and J. Zhu, “Aligned single-crystalline Si nanowire arrays for photovoltaic applications,” Small, vol. 1, pp. 1062-7, Nov 2005.
[34]. Hui Fang, YinWu, Jiahao Zhao and Jing Zhu,” Silver catalysis in the fabrication of silicon nanowire arrays,” Nanotechnology, vol. 17, pp. 3768–3774, 2006.
[35]. T. QIU, X.L. WU, G.G. SIU, and PAUL K. CHU,” Intergrowth Mechanism of Silicon Nanowires and Silver Dendrites,” Journal of Electronic Materials, vol. 35, no. 10, 2006.
[36]. Yang, R., et al. (2011). "Observation of Raman g-peak split for graphene nanoribbons with hydrogen-terminated zigzag edges." Nano Lett 11(10): 4083-4088.
[37]. Tu, Z., et al. (2014). "Controllable growth of 1–7 layers of graphene by chemical vapour deposition." Carbon 73: 252-258.
[38]. “ 氨氣”維基百科.
[39]. Blum, Alexander (1975). "On crystalline character of transparent solid ammonia". Radiation Effects and Defects in Solids. 24 (4): 277. doi:10.1080/00337577508240819
[40]. Bai, H., et al. (2009). "Composite nanofibers of conducting polymers and
hydrophobic insulating polymers: Preparation and sensing applications."
Polymer 50(14): 3292-3301.
[41]. Itagaki, Y., et al. (2005). "Toxic gas detection using porphyrin dispersed
polymer composites." Sensors and Actuators B: Chemical 108(1-2): 393-397.
[42]. Mohammadi, M. R. and D. J. Fray (2009). "Development of nanocrystalline
TiO2–Er2O3 and TiO2–Ta2O5 thin film gas sensors: Controlling the physical
and sensing properties." Sensors and Actuators B: Chemical 141(1): 76-84.
[43]. Li, C., et al. (2009). "Conducting polymer nanomaterials:
electrosynthesis and applications." Chem Soc Rev 38(8): 2397-2409.
[44]. Wagner, T., et al. (2013). "Mesoporous materials as gas sensors." Chem Soc
Rev 42(9): 4036-4053.
[45]. Li, C. and G. Shi (2012). "Three-dimensional graphene architectures."
Nanoscale 4(18): 5549-5563.
[46]. Kreno, L. E., et al. (2012). "Metal-organic framework materials as chemical
sensors." Chem Rev 112(2): 1105-1125.
[47]. Yavari, F., et al. (2011). "High sensitivity gas detection using a macroscopic
three-dimensional graphene foam network." Sci Rep 1: 166.
[48]. Lee, C., et al. (2012). "Graphene-based flexible NO2 chemical sensors." Thin
Solid Films 520(16): 5459-5462.
[49]. Arsat, R., et al. (2009). "Graphene-like nano-sheets for surface acoustic wave
gas sensor applications." Chemical Physics Letters 467(4-6): 344-347.
[50]. Qazi, M., et al. (2007). "Trace gas detection using nanostructured graphite
layers." Applied Physics Letters 91(23).
[51]. Zhang, J., et al. (2012). "Soft-lithographic processed soluble micropatterns of
reduced graphene oxide for wafer-scale thin film transistors and gas sensors."
J. Mater. Chem. 22(2): 714-718.
[52]. 國立台灣科技大學貴儀中心JEOL6500場發射掃描式電子顯微鏡
[53]. 國立台灣科技大學材料科學與工程系顯微拉曼光譜儀
[54]. 國立中央大學貴儀中心X射線光電子能譜儀系統
[55]. ''Scanning Electron Microscopy and X-Ray Microanalysis'' Springer
[56]. ''EDS 能量色散X-射線光譜'' EAG
[57]. Placzek G.: "Rayleigh Streeung und Raman Effekt", In: Hdb. der Radiologie, Vol. VI., 2, 1934, p. 209
[58]. Jeanmaire DL, van Duyne RP. Surface Raman Electrochemistry Part I. Heterocyclic, Aromatic and Aliphatic Amines Adsorbed on the Anodized Silver Electrode. Journal of Electroanalytical Chemistry (Elsevier Sequouia S.A.). 1977, 84: 1–20.
[59]. Chao RS, Khanna RK, Lippincott ER. Theoretical and experimental resonance Raman intensities for the manganate ion. J Raman Spectroscopy. 1974, 3: 121.
[60]. Matousek P, Clark IP, Draper ERC; Subsurface Probing in Diffusely Scattering Media using Spatially Offset Raman Spectroscopy. Applied Spectroscopy. 2005, 59: 393.
[61]. Barron LD, Hecht L, McColl IH, Blanch EW. Raman optical activity comes of age. Molec. Phys. 2004, 102 (8): 731-744.
[62]. 麻茂生 XPS譜峰結構與化學態分析
[63]. K. Oura; V.G. Lifshifts; A.A. Saranin; A. V. Zotov; M. Katayama. Surface
Science. Springer-Verlag, Berlin Heidelberg New York. 2003: 104.
[64]. Himpsel, F. J. ; McFeely, F. R. ; Taleb-Ibrahimi, A.; Yarmoff, J. A.; Hollinger, G. Microscopic structure of the Si2/Si interface. Physical Review B (American Physical Society). 1988-09-15, 38 (9): 6084.
[65]. K. Oura; V.G. Lifshifts; A.A. Saranin; A. V. Zotov; M. Katayama. Surface Science. Springer-Verlag, Berlin Heidelberg New York. 2003: 101.
[66] Prekodravac, J., et al. (2015). "The effect of annealing temperature and time on
synthesis of graphene thin films by rapid thermal annealing." Synthetic Metals 209:
461-467.
[67] Jang, C. W., et al. (2013). "Rapid-thermal-annealing surface treatment for restoring
the intrinsic properties of graphene field-effect transistors." Nanotechnology 24(40):
405301.
[69] Gautam, M. and A. H. Jayatissa (2012). "Ammonia gas sensing behavior of graphene surface decorated with gold nanoparticles." Solid-State Electronics 78: 159-165.
[70] Seekaew, Y., et al. (2014). "Low-cost and flexible printed graphene–PEDOT:PSS gas
sensor for ammonia detection." Organic Electronics 15(11): 2971-2981.
[71] Jebreiil Khadem, S. M., et al. (2014). "Investigating the effect of gas absorption on the
electromechanical and electrochemical behavior of graphene/ZnO structure, suitable for highly selective and sensitive gas sensors." Current Applied Physics 14(11): 1498-1503.
[72] Ben Aziza, Z., et al. (2014). "Graphene/mica based ammonia gas sensors." Applied Physics Letters 105(25)
[73] Song, H., et al. (2017). "Sensitivity investigation for the dependence of monolayer
and stacking graphene NH 3 gas sensor." Diamond and Related Materials 73: 56-61.
[74] Wu, J., et al. (2018). "Boosted sensitivity of graphene gas sensor via nanoporous thin
film structures." Sensors and Actuators B: Chemical 255: 1805-1813.
[75] Saravanan, A., et al. (2018). "Hierarchical morphology and hydrogen sensing
properties of N2-based nanodiamond materials produced through CH4/H2/Ar plasma treatment." Applied Surface Science 457: 367-375.
[76] “慧斯燈電橋”維基百科
[77] Feng, J., et al. (2017). "Facile synthesis silver nanoparticles on different xerogel supports as highly efficient catalysts for the reduction of p-nitrophenol." Colloids and Surfaces A: Physicochemical and Engineering Aspects 520: 743-756.
[78] Bazylewski, P., et al. (2015). "The characterization of Co-nanoparticles supported on graphene." RSC Advances 5(92): 75600-75606
[79] Li, Y., et al. (2017). "Electrochemical synthesis of phosphorus-doped graphene quantum dots for free radical scavenging." Phys Chem Chem Phys 19(18): 11631-11638.
[80] Bradley, S. J., et al. (2017). "Heterogeneity in the fluorescence of graphene and graphene oxide quantum dots." Microchimica Acta 184(3): 871-878.
[81] Peng, B., et al. (2017). "High-Performance and Low-Cost Sodium-Ion Anode Based on a Facile Black Phosphorus−Carbon Nanocomposite." ChemElectroChem 4(9): 2140-2144.
[82] Zhang, L., et al. (2017). "Thickness Measurement of Oxide and Carbonaceous Layers on a 28Si Sphere by XPS." IEEE Transactions on Instrumentation and Measurement 66(6): 1297-1303.