本論文中，我們將從理論與實驗上討論以矽晶圓為基板的中空弧形全方向反射鏡轉角波導，並利用非晶相矽與二氧化矽以交互堆疊方式製作高反射率的布拉格反射鏡，將光有效的侷限在波導空氣核中。在此論文中，我們利用二維方式的時域有限差分法（Finite-Difference Time-Domain，FDTD），三維方式的有限差分光傳播法(Finite-Difference Beam Propagation Method，FD-BPM) 模擬出0度到90度的轉角損耗，並利用感應耦合電漿蝕刻機(Infuctively coupled plasma, ICP)在矽基板上蝕刻約50um x 50um的凹槽，電漿輔助化學氣相沉積系統(Plasma-Enhanced Chemical Vapor Depostition, PECVD)沉積六對Si/SiO2的多層膜，Si及SiO2的膜厚分別是0.111um及0.262um，最後透過晶片鍵結技術完成本論文所討論的中空弧形轉角光波導，此中空弧形轉角光波導將會操作在光波長為1550nm，由量測結果得知，轉角損耗隨著轉角角度增加而增加，轉角損耗最大值約為TE模態21dB、TM模態23dB，此時轉角角度為70度，當轉角角度大於70度時，轉角損耗過大，因而無法量測。

In this work, we demonstrate theoretically and experimentally the air core bent waveguides composed of omni-directional reflectors on a silicon substrate. The amorphous silicon and the silicon oxide are used for high index-contrast Bragg reflectors. The transmission efficiency of the bent waveguides with bending angle for 0-90 degree is calculated by the two-dimensional finite-difference time-domain method and the three-dimensional beam propagation method. The 50um x 50um groove of the silicon substrate is etched by inductive coupled plasma (ICP). Plasma enhanced chemical vapor deposition (PECVD) is used to depositing six pairs of amorphous-silicon and silicon-oxide (0.111um and 0.262um) on the patterned substrate and another blank (100) silicon substrate. These two substrates were bonded to form the hollow waveguides. The bent waveguide operate in 1550 nm. In experimental results, bending loss increases with bending angle. The maximum bending loss for TE mode and TM mode is 21dB and 23dB, respectively.

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