臺灣博碩士論文加值系統

本論文中在絕緣層上覆矽(Silicon-on-insulator, SOI)上，利用多模干涉(Multimode interference, MMI)耦合器和對稱的曲線錐形波導組合，獲得了最佳的絕熱模態轉換(Adiabatic mode conversion)和最高的輸出功率。而1x1 MMI 耦合器使用了三種不同寬度 Wmmi，分別為 4 um / 8 um / 12 um，並且多模波導長度 Lmmi 分別為 31 um / 121.5 um / 270 um，與設計的 1° 線性錐形波導相連，線性錐形波導的輸入端寬度 Ws 為 0.4 um，並模擬線性錐形波導的輸出端寬度 Wt 從2 um / 4 um / 6 um至 0.6 um，間隔為0.2 um，得出其元件的輸出功率分別為 0.984 / 0.982 / 0.984時，有最短的 1° 線性錐形波導輸出端寬度 Wt 分別為 1.4 um / 2 um / 2.4 um，且線性錐形波導長度 Lt分別為 57.3 um / 91.7 um / 114.6 um。1x1 MMI 耦合器與最短長度的線性錐形波導組合時，有最大的發散角 θmax，分別為11° / 8° / 9°，此時的線性錐形波導長度為 5.3 um / 11.4 um / 12.7 um，其輸出功率為 0.950 / 0.959 / 0.954。有最大發散角 θmax的最短長度線性錐形波導與發散角 θ 為 1° 時的線性錐形波導長度 Lt相比較，各別縮短 90.8 % / 87.6 % / 88.9 %。
凹型錐形曲線波導 (Concave curve taper)和凸型錐形曲線波導 (Convex curve taper)，在凹型錐形曲線波導的最大發散角θmax為 7° / 3° / 4° 時，凹型錐形曲線波導長度分別為 8.2 um / 30.6 um / 28.6 um，其輸出功率分別為 0.951 / 0.969 / 0.960，而有最大發散角 θmax的最短長度凹型錐形曲線波導與發散角 θ 為 1° 時的線性錐形波導的長度 Lt相比較，各別縮短了 85.7 % / 66.6 % / 75 %。而凸型錐形曲線波導在最大的發散角 θmax分別為20° / 11° / 12°時，凸型錐形曲線波導長度分別為 2.8 um / 8.3 um / 9.5 um，輸出功率分別為 0.952 / 0.956 / 0.954，而有最大發散角 θmax的最短長度凸型錐形曲線波導與發散角 θ 為 1° 時的線型錐形波導的長度 Lt相比較，各別縮短 95.1 % / 90.9 % / 91.7 %。

In this paper, the combination of a multimode interference (MMI) coupler and a symmetric curved tapered waveguide on silicon-on-insulator (SOI) is used to achieve the best adiabatic mode conversion and the highest output power. A 1x1 MMI coupler with three different widths(Wmmi) of 4 um / 8 um / 12 um, and three different multimode waveguide lengths(Lmmi) of 31 um / 121.5 um / 270 um, is connected to a designed 1° linear tapered waveguide with an input width of Ws = 0.4 um. The output width of the linear tapered waveguide is simulated to range from 6 um to 0.6 um with a step of 0.2 um, resulting in output widths of Wt = 1.4 um / 2 um / 2.4 um for the 1° linear tapered waveguide with lengths of Lt = 57.3 um / 91.7 um / 114.6 um, respectively, with output powers of 0.984 / 0.982 / 0.984. When the 1x1 MMI coupler is combined with the shortest length linear tapered waveguide, the maximum divergence angle θmax is 11° / 8° / 9°, respectively, and the output powers are 0.950 / 0.959 / 0.954. The shortest length linear tapered waveguide with the maximum divergence angle θmax is compared to the linear tapered waveguide with a divergence angle of 1°, and its length is shortened by 90.8 % / 87.6 % / 88.9%, respectively.
In concave curve tapers and convex curve tapers, the length of the concave curve taper with a maximum divergence angle of θmax = 7° / 3° / 4°, respectively, is 8.2 um / 30.6 um / 28.6 um, and the output powers are 0.951 / 0.969 / 0.960. The shortest length concave curve taper with the maximum divergence angle θmax is compared to the linear tapered waveguide with a divergence angle of 1°, and its length is shortened by 85.7% / 66.6% / 75%, respectively. The length of the convex curve taper with maximum divergence angles of θmax = 20° / 11° / 12°, respectively, is 2.8 um / 8.3 um / 9.5 um, and the output powers are 0.952 / 0.956 / 0.954. The shortest length convex curve taper with the maximum divergence angle θmax is compared to the linear tapered waveguide with a divergence angle of 1°, and its length is shortened by 95.1 % / 90.9 % / 91.7 %, respectively.

中文摘要
ABSTRACT
致謝
目錄
表目錄
圖目錄
符號說明
第一章 緒論
1.1 論文大綱
1.2 研究動機
第二章 結構
2.1 絕緣層上覆矽結構
2.2 有效折射率(Effective index)
2.3 脊狀波導和多模干涉耦合器可存在模態
第三章 最大發散角公式
3.1 1x1 MMI 多模干涉耦合器
3.2 線性錐形波導
3.3 線性錐形波導寬度
3.4 線性錐形波導最大發散角
第四章 最佳錐形曲線波導
4.1 錐形曲線波導結構
4.2 凹型錐形曲線波導
4.3 凸型錐形曲線波導
第五章 結論
未來展望
參考文獻

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