隨著資料中心對高速、低功耗光互連需求日益提升，矽光子環形調製器（Microring Modulator, MRM）以其體積小、低功耗與 CMOS 相容性，成為未來光電整合的重要元件。然而元件尺寸縮小易導致彎曲損耗與模態不匹配等問題。本研究旨在設計一款極小尺寸且高效能的環形調製器，以突破元件微縮過程中的瓶頸。
本論文提出以三次 Bézier 曲線優化環形波導內圈，外圈則維持圓形以支持回音壁模態，有效降低彎曲損耗並提升模態穩定性。此外，在調製區採用優化 L 型 PN接面設計，增加光場與空乏區交疊，提高調製效率。研究透過 Lumerical FDTD 與DEVICE 軟體進行光電模擬，並利用粒子群演算法（PSO）最佳化結構參數，同時使用 ADS 軟體分析元件 RC 頻寬，最終於 INTERCONNECT 驗證訊號完整度。
結果顯示，所設計之環形調製器在半徑僅 2.5 μm 下，具有 44.87 nm 的自由光譜範圍（FSR），在 0至–4 V 偏壓下可達 12 dB 以上的動態消光比、共振波長偏移 145.2 pm/V，RC 頻寬與光子壽命頻寬分別達 31.7 GHz 與 67.03 GHz，總調製頻寬達 28.63 GHz；於傳輸速率 10 至 50 Gbps 下之眼圖交叉比約 56%，展現優高速調製潛力。
本研究提出之微環調製器設計與驗證流程，展示矽光子元件於極小尺寸下的高效能與低功耗高速傳輸潛力，未來可望應用於高密度波分多工（WDM）系統與高速光收發器，推動光電共封裝及光互連技術發展。

As data centers increasingly require high-speed, low-power optical interconnects, silicon photonic microring modulators (MRMs) have emerged as critical components due to their compact size, low power consumption, and compatibility with CMOS technology. However, reducing device dimensions often introduces challenges such as increased bending losses and mode mismatch. To address these issues, this research develops an ultra-compact, high-performance silicon photonic MRM.
The proposed device employs a cubic Bézier curve to optimize the inner waveguide geometry while maintaining a circular outer boundary to support whispering gallery modes, significantly reducing bending loss and improving mode stability. Additionally, an optimized L-shaped PN junction structure enhances the overlap between the optical mode and depletion region, increasing modulation efficiency. Optical and electrical simulations were performed using Lumerical FDTD, DEVICE, ADS software, and particle swarm optimization (PSO) for structural refinement, with final system-level validation conducted via INTERCONNECT.
Simulation results demonstrate that the designed MRM, with a radius of just 2.5 μm, achieves a free spectral range (FSR) of 44.87 nm, a dynamic extinction ratio greater than 12 dB, and a resonance wavelength shift of 145.2 pm/V under biases from 0 to–4 V. The device exhibits RC and photon lifetime bandwidths of 31.7 GHz and 67.03 GHz, respectively, with a total modulation bandwidth of 28.63 GHz. Eye-diagram analyses at data rates of 10 to 50 Gbps confirm excellent signal integrity, maintaining a stable eye-crossing ratio of approximately 56%. These results highlight the potential of the proposed MRM for future high-density wavelength-division multiplexing (WDM) and high-speed optical interconnect applications.

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