在傳統銅纜線訊號傳輸速度逐漸受到限制下，取而代之的是光傳輸系統，而光積體電路擁有高傳輸速度、低成本及節能的優勢，除了運用於資料運算及雲端服務，現今也開始拓展在醫療及軍用等領域的應用，因此矽光子成為新世代熱門的研究方向。
本論文利用比利時微電子研究中心所提供之矽光子製程，在絕緣層覆矽基板上製作光被動元件。首先設計方向耦合器使能於1300 nm~1320 nm波長範圍有穩定的耦合效率，並用以連接兩組馬赫-曾德爾干涉儀實現光交織器。然而，實際量測的耦合效率與設計值相異，從模擬的方式探討後發現，由於設計時使用的2.5D FDTD會將垂直軸(垂直於晶圓表面)方向忽略，因此未計算到此方向的耦合而造成誤差，論文中也驗證了3D FDTD結果與量測結果較為相符。
因為耦合效率的差異下，使光交織器的通帶及阻帶產生分波的現象，原先預計耦合效率為0.5而實際為0.82，故當其耦合效率非0.5時，使得兩輸出端光明滅比互相抑制。此外亦透過溫度控制器使光交織器波長位移，經過線性推估為0.061 nm/℃。

The inter-connection with conventional copper wires has rather limited bandwidth to fulfill the increasing demands of nowadays communication needs. Optical interconnect and transmission systems start to take over the copper wires as the high-capacity transmission media. Silicon photonic circuits have the advantages of high transmission speed, low cost, and energy saving. Besides the applications to high-performance computing and cloud services, silicon photonics has been also applied to realize the functionality for bio-medical and military fields. As a result, silicon photonics is becoming the hot research field recently.
This thesis investigates the realization of optical passive elements with the silicon-on-insulator (SOI) platform provided by IMEC. We first design the directional coupler with stable coupling coefficient over a wavelength range of 1300 nm to 1320 nm. The Mach-Zehnder interferometers formed of the directional couplers and waveguides are cascaded to realize optical interleavers. The measured device characteristics of the fabricated couplers and optical interleavers are found to be different from the designed values. After detailed investigations, the 2.5D-FDTD simulation that was adopted for device analysis was found to cause the difference between experiments and simulations. This is due to the fact that the 2.5D-FDTD method use effective index to approximate the vertical direction of the waveguide and thus ignore the coupling along this direction. The simulation using 3D-FDTD results in better matching to the measured ones.
The difference in the coupling coefficient of directional coupler leads to the imperfect characteristics of the optical interleaver where the passband and stopband are not flat. The expected coupling coefficient of the coupler is 0.5 but the real value is 0.82 with the 3D-FDTD simulation. This results in the reduced extinction ratio of the optical interleaver. For practical applications, a temperature controller is used to tune the optical interleaver and obtain a wavelength tuning of 0.061 nm/℃.

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