- 學位論文
微波電漿系統之電磁場模擬分析研究
A Study of Microwave Plasma System Electromagnetic Fields Simulation
摘要
電漿技術已成為高科技產業關鍵技術，微波電漿在鑽石薄膜沈積，半導體、奈米與光電材料製造領域與學術研究上扮演重要的角色。由於微波電漿系統之電磁場分佈是影響電漿運作、薄膜成長率與薄膜品質的重要因數，為了深入瞭解本實驗室既有微波電漿系統效能與運作機制，進而增加製程控制與預測能力，本研究使用高頻結構模擬軟體（HFSS）模擬微波電漿系統改變腔體幾何形狀、材料時電磁場之分佈、阻抗特性之變化、並預估發生共振區域是否位於基材處以增進微波功率吸收，避免功率損失，模擬與實驗結果作比較一致顯示本系統不易形成均勻電漿，與電磁場分佈相關。再以模擬結果與相關文獻為基礎，模擬改進既有微波電漿系統（1）調整腔體結構使電磁場集中於石英管內不使擴散至下方大型腔體，以集中能量鍍膜，避免能量損失。（2）透過腔體耦合設計將矩形波導管 模式轉變成圓柱共振腔體 或 模式，在避免激發其它波導模式的條件下設計腔體，使電漿易於點燃、增加單位體積功率密度，改進小管徑電漿均勻性問題、適度增加電漿範圍，提高電漿系統效能。
並列摘要
Plasma technology is the key technology of high –Tech industry, it play very important role in different areas , like diamond films, semi-conductor, and nano material, etc. Microwave plasma is the important factor of plasma operation, thin film growth rate and thin film quality, to understand the performance and process of microwave plasma system in this experiment, and increase the process control and prediction ability. In this research, HFSS was used to simulate the change of cavity geometry, material, the electromagnetic fields distribution, impedance and predict if the region of resonant concentrate on the surface to enhance microwave power absorbed and avoid power loss. The result of this simulation and the experimental in this research are both indicated this system is not easy to form the uniform plasma, also indicate the plasma density distribution based on a breakdown field algorithm. According to the simulation result and related thesis, to enhance the microwave plasma simulation system. To modify the cavity geometry, let electromagnetic filed distribution concentrate on quartz glass tube without separate to chamber, and avoid energy loss. To modify the couples field propagation of cavity geometry, rectangular waveguide mode changed to cylindrical cavity mode or mode, it can avoid to excite other mode, the plasma become easy to launch, increase the power density, plasma uniform, and region of plasma, it will enhance plasma system performance。