隨著科技技術發展，人類對於通訊技術與計算頻寬的逐漸變高，急切需要一個低能耗、高帶寬的技術來取代銅導線在傳輸之間的損耗。矽光子技術得益於與CMOS製程技術的高度結合，與其高帶寬、低損耗的優勢。在未來與AI應用還有晶片內連接技術上是強力之競爭者。因此本論文研究為矽光子元件之一的微環形共振腔之衍生結構，為微環形共振腔干涉儀。且此論文側重點在於結構造成之消光比提升。 雖然微環形共振腔在模擬上也可以達到非常深之消光比，但是受限於其元件之耦合強度，在實際製程上並無法見證其高消光比之傳遞頻譜，這也是本論文選用此結構之原因。
首先在模擬上會先使用時預有限差分法(FDTD)對微小尺度之結構進行模擬，確認傳遞特徵後使用數值模擬的方式進行後續大尺度之結構模擬。本論文透過兩種模擬工具模擬出大尺度結構之傳遞場型，探討不同結構長度、耦合因數，對於消光比之影響。並模擬出在不同等效折射率下最終傳遞場型的消光比變化。且可以使用調製器對於特定波長之共振峰進行開關與消光比之調製。此結構與其調變器之使用能進一步提升在同一試片上之光學通訊上之遠距離訊號之傳遞品質，與光學偵測器、傳感器上的探測精度。
元件製程的部分，本論文選擇氮化矽作為波導材料，使用i-line Stepper步進式曝光機進行光學微影製程。 在優化製程後實現高品質因子之試片，且也透過全片製程驗證了大量生產之可能性。 量測部分本論文使用1550 nm之光通訊波段進行傳遞頻譜之分析，驗證了本論文在模擬部分之消光特性。最後本論文也研究如何提升環腔品質，驗證了一些細小微結構對於品質因子之提升，可以達到50%。 透過調製器之作用讓本論文得到相比於無調製器結果，有調製器的結構讓本論文的消光比提升了16 dB。總體達到35 dB之消光值，且本論文也在模擬上見證了4串聯結構之80 dB消光元件。利用此元件特性可以讓本論文在通訊與感測領域有更多應用。
使用i-line Stepper步進式曝光機進行微影製程能讓本論文達到大量生產且耗費成本相較於現行之DUV 、EUV深紫外光掃描式曝光機低。且能生產出不錯之高品質因子試片。此給予本論文一種除了成本低廉之接觸式曝光機，與時間花費成本高之掃描式電子直寫系統設備之外的一個選擇性。

This thesis focuses on a derivative structure of silicon photonic devices, specifically the microring resonator interferometer, which is a strong contender for future applications in AI and on-chip interconnect technologies due to its high bandwidth and low loss advantages, as well as its high integration with CMOS process technology. The emphasis of this paper is on the enhancement of the extinction ratio( ER) caused by the structure. Although microring resonators can achieve a very deep extinction ratio in simulations, the high extinction ratio of the transmission spectrum cannot be witnessed in actual processes due to the limited coupling strength of the components, which is why we chose this structure.

Initially, the Finite-Difference Time-Domain (FDTD) method is used for simulating small-scale structures to confirm their transmission characteristics, followed by numerical simulations for larger-scale structures. We use two simulation tools to model the transmission field patterns of large-scale structures, exploring the impact of different structure lengths and coupling factors on the extinction ratio. We also simulate the changes in the extinction ratio of the final transmission field pattern under different refractive indices. Modulators can be used to switch and modulate the extinction ratio of specific resonant peaks. This structure and its modulators can further enhance the quality of long-distance signal transmission in optical communications on the same wafer, as well as the detection precision of optical detectors and sensors.

For the component process, this paper chooses silicon nitride as the waveguide material and uses an i-line Stepper photolithography machine for the optical lithography process. After process optimization, high-quality factor samples are realized, and the feasibility of mass production is verified through full-wafer processing. For the measurement part, we use the 1550 nm optical communication band to analyze the transmission spectrum, verifying the extinction characteristics predicted in our simulations. Finally, we study how to improve the quality of the ring cavity, verifying that some fine microstructures can increase the quality factor by up to 50%. Through the action of the modulator, we achieved an extinction ratio improvement of 16 dB compared to the unmodulated structure, reaching a total of 35 dB. We also witnessed in simulations an 80 dB extinction component of 4 cascaded structures. The characteristics of this component can enable more applications in the fields of communication and sensing.

Using the i-line Stepper photolithography machine for the lithography process allows us to achieve mass production at a lower cost compared to current DUV and EUV deep ultraviolet scanning lithography machines. It also produces high-quality factor samples. This gives us an alternative to the low-cost contact lithography machines and the high time-cost scanning electron beam direct writing systems.

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