層狀二維材料(Two-dimensional materials)不但具有特殊的電導、熱導、光學與機械特性，且易與現今元件製程整合，故被視為很有潛力可取代矽材元件之新穎材料。
黑磷烯(Phosphorene)為一新興層狀二維材料，係由磷原子組成之六角呈皺褶蜂巢狀晶格結構(Lattice structure)，具有良好的電性與光學性質，如擁有石墨烯(Graphene)缺乏之電子能隙(Bandgap)，且具有較高之載子移動率(Carrier mobility)及開關比(On-off ratio)，使其成為奈米電子元件材料之明日之星。然高功能奈米電子元件亦伴隨高功率密度需求，所產生之高溫常使得材料物理性質改變並影響電子元件之性能，因此有效掌握黑磷烯之熱力及熱機械性質，已成為一重要研究課題。此外，由於製程技術之限制，黑磷烯於製作過程中常易產生缺陷(Defect)，而此缺陷也將深深影響黑磷烯之電性與機械性質，亦值得深入探討。
另外，低維度奈米結構因具有奈米尺寸、單晶結構及獨特之尺寸量子效應等優點，已漸被應用於微奈米電子與機電系統中。因此，將層狀二維材料轉化為一維結構如奈米管、奈米線或奈米帶等，並探討其物理性質是必要的。
本論文首先結合分子動力學(Molecular dynamics)及Nosé-Hoover Langevin熱容法(Thermostat)進行黑磷烯(Phosphorene sheet)之熱力與熱機械性質分析，包含楊氏模數、剪切模數、比熱與線性熱膨脹係數等，並進一步探討不同缺陷種類與缺陷率對黑磷烯之影響。最後，針對不同結構之單層奈米黑磷管(Phosphorene nanotube)，包括鋸齒型(Zigzag)、扶手型(Armchair)與混合型(Hybrid)之熱力與熱機械性質進行計算。計算所得結果與文獻相較頗為脗和，顯示本論文分析方法之正確及有效性。
本論文之成果可供未來以黑磷烯與奈米黑磷管為本之奈米電子元件設計與開發之參考。

Two-dimensional materials not only possess distinctive electrical and thermal conductivities, optical and mechanical properties, but also incline to be integrated with device manufacturing process. Therefore, it is regarded as a promising material to replace silicon materials.
　　Phosphorene, a novel two-dimensional puckered honeycomb lattice of phosphorus, possesses some remarkable electrical and optical properties, such as it has a direct bandgap, relatively high carrier mobility and on/off ratio, thereby making it to be a rising star among the electronics device materials. However, when applied in electronic devices, the phosphorene-based nano-scale electronic components often suffer from high temperature loading, which would change the physical properties of phosphorene and so affect the electrical performance. Well grasp of the thermodynamic and thermo-mechanical properties of phosphorene is crucial for successful implementation of the nano-scale electronic components. Besides, due to the limitation of fabrication technologies nowadays, atomistic defects are often perceived in phosphorene during the manufacturing process and affect the electrical and mechanical properties. Thus, the second goal of the study is to perform a systematic investigation of the effects of atomistic defects on the thermodynamic and thermo-mechanical properties of phosphorene.
　　Because of the distinct size-dependent quantum effects together with nanosize and single crystal structure, low-dimensional structures are potential for use in nano-scale electronic or electromechanical devices. Hence, converting two-dimensional sheet to one-dimensional structure, such as nanotubes, nanowires or nanoribbons and investigate their physical properties are necessary.
The work attempts to assess the thermodynamic and thermo-mechanical properties of phosphorene at constant temperature though the canonical ensemble MD model using a Nosé-Hoover Langevin (NHL) thermostat, including Young’s modulus, (Poisson’s ratio), shear modulus, specific heat and linear coefficient of thermal expansion. In addition, the defect effects of phosphorene is also examined. The thermodynamic and thermo-mechanical properties of phosphorene nanotubes of zigzag, armchair and hybrid type are investigated as well. The simulation results are compared with the literature data to demonstrate the validity of the proposed simulation model. In closing, the present work can be beneficial to the design and development of phosphorene-based nano-scale electronic components in future.

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