本論文致力於研究不同形狀的絕緣層覆矽 (silicon-on-insulator, SOI)錐狀波導之理論分析與數值模擬。首先，我們介紹這七種不同形狀的錐狀波導之基本理論，並利用Photon Design模擬軟體設計出這七種不同形狀的錐狀波導系統。根據這七種不同形狀的錐狀波導之優點與缺點，我們可以從中分析出在因應的需求下應用何種形狀的錐狀波導系統，藉由此分析選擇出最佳且合適的錐狀波導。此外，本論文著重於利用絕緣層覆矽為基礎材料以具體實現不同形狀的錐狀波導，並以縮短元件的尺寸、增加元件的操作頻寬和實際製程的容忍性為研究方向，以促進高密度積體光路的發展。

This thesis is devoted to the theoretical investigation and numerical simulations of different types of waveguide tapers based on silicon-on-insulator (SOI) platform. We begin by introducing the operation theory of the seven types of waveguide taper systems, and then we use the EigenMode Expansion (EME) method to perform the simulations. Seven waveguide taper systems are analyzed, including linear taper, Gaussian taper, two types of parabolic taper, two types of exponential taper and M&B taper. And then we compare these seven types of waveguide tapers to evaluate the performance of each taper. We analyze the shape, the length, the wavelength robustness and the fabrication tolerance of the tapers. Each taper has its own advantages and disadvantages. We can choose the most suitable type of waveguide taper system under the requirements we need.

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