矽基片B型抗諧振反射光波導結構光子晶體波導之設計,研製,與特性量測

Abstract

本研究主要是探討矽基片B型抗諧振反射光波導(ARROW-B)結構結合三角晶格光子晶體以形成三維波導元件之設計、製作與特性量測。此波導元件結構在水平方向上，利用二維光子晶體能隙(photonic band gaps)導波機制；而在垂直方向上，利用抗諧振條件形成準單模光波導結構。此機制可將導光核心層作厚，以和單模光纖有效率耦合。首先利用轉移矩陣法(TMM)探討抗諧振反射光波導結構的模態特性，再利用平面波展開法(PWE) 模擬二維光子晶體的光子能帶和傳輸特性，接著結合上述方法在結構上設計直波導與雙60度彎折波導等元件。最後，使用有限差分時域法(FDTD)來模擬光子晶體波導傳輸行為，計算出傳輸波長□為1.55□□um 之ARROW-B結構之光子晶體直波導與雙60度彎折波導的傳輸效率。實驗則利用國家奈米元件實驗室的製程機台製作出ARROW-B結構之三角晶格光子晶體波導元件，最後以本系所奈米光電與生物光電實驗室架設的光學量測系統量測ARROW-B結構之光子晶體直波導與雙60度彎折波導元件傳輸效率，並且討論量測效率與設計預期差異的原因和提出製程改善方法。

In this study, the design, fabrication and characterization of ARROW-B-based photonic crystal waveguides are investigated. The structure confines light by the photonic crystal band gaps in the lateral direction and the ARROW-B structure in the vertical direction. Based on ARROW-B structure, a thick guiding core can be formed which provides efficient coupling with a single-mode fiber. We began with analyzing the modal characteristics of ARROW-B structure with the transfer matrix method (TMM). The photonic band structures and transmission behaviors of the two-dimensional photonic crystal waveguides are discussed by method plane wave expansion (PWE). The ARROW-B-based straight PC waveguide and double-60。bent waveguide were designed and the finite difference time domain method (FDTD) was utilized to simulate the transmission behaviors of the waves in both straight and double-60。 bent waveguides at the 1.55 um wavelength. We fabricated the ARROW-B-based PC waveguide with the equipments in the National Nano Device Laboratories and measured the transmission power with the optical systems in our laboratory. The propagation losses of straight waveguides and bend losses of double-60。bent waveguide were evaluated. Finally, we discussed the difference of simulations and measurement and also proposed some suggestions to improve the fabrication.