隨著近年來數據傳輸需求的大幅增加，需要具更大頻寬的發射器來達到100-Gb/s以上位元率的高速數據傳輸。光通訊傳輸系統相比於傳統的電通訊傳輸系統，具有兩個主要優勢：首先，它能夠實現更低的能量損耗；第二，它具有更快的傳輸速率，可以實現更高效率的數據傳輸。
本論文研究目標為探討及設計模擬單通道傳輸速率100-Gb/s PAM-4訊號的矽光子環形調變器，首先按照環形調變器元件設計參數及元件特性關係建立設計流程，接著按照設計流程進行環形調變器的矽波導尺寸、佈植濃度和方式、耦合間距等模擬和分析，最後設計出三種類型的環形調變器，分別為平行雙環形調變器、可調式耦合器加平行雙環形調變器以及兩段式Z形佈植單環形調變器，其優點為可以直接對環形調變器給予兩路NRZ訊號並在光學調變的情況下產生PAM-4訊號，降低驅動電路端的訊號處理需求。
利用這三種環形調變器來達到單通道傳輸速率100-Gb/s PAM-4訊號發射器，所設計之發射器種類總共有三種，每種發射器都有各自的優缺點，並分析當輸入訊號不同的上升/下降時間對眼圖的參數的影響。所設計的矽光子環形調變器已下線至比利時歐洲跨校際微電子中心(IMEC)製作，未來經過量測，可驗證其作為單通道傳輸速率100-Gb/s PAM-4訊號發射器之可行性。

With the significant increase in data transmission demands in recent years, there are urgent needs for transmitters with larger bandwidth to support high-speed data transmission of 100-Gb/s and above data rates. Optical communication systems have become a more attractive choice, compared to traditional electrical communication systems because they have two main advantages: lower energy consumption and faster transmission rates.
The objective of this study is to investigate and design a silicon photonics ring modulator for achieving single-channel 100-Gb/s PAM-4 signal transmission. The design process is established based on the relationship between the design parameters and the characteristics of the ring modulator components fabricated with IMEC . The silicon waveguide dimension, implantation concentration and profile, and the coupling spacing of the ring modulator are simulated and analyzed. Three types of ring modulators, including parallel dual ring modulator, tunable directional coupler with parallel dual ring modulator and two segment single ring modulator, are designed and compared.
Using these three types of ring modulators, the single-channel 100-Gb/s PAM-4 signal transmitter can be realized. The advantages and disadvantages of the three types of transmitters are compared. The impact of different rise/fall time of the input signal on the eye diagram is analyzed. The designed 100-Gb/s ring modulators have been tape-out to IMEC (Interuniversity Microelectronics Centre) in Belgium for fabrication with silicon photonics platform. The feasibility for 100-Gb/s data transmission with these silicon photonics ring modulators will be verified after the fabrication is finished.

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