與光纖高效率耦合之矽基片上抗諧振反射光波導(ARROW)結構光子晶體波導元件之設計、研製及特性量測

Abstract

本計畫之目的在基於過去十餘年之在矽基片上抗諧振反射式光波導 （antiresonant reflecting optical waveguide, ARROW）元件設計與研製之經驗與成 果，應用在光波段工作之光子晶體元件上，開發『與光纖高效率耦合之矽基片上 抗諧振反射光波導(ARROW)結構光子晶體波導三維元件』，完成元件設計、並 進行元件研製及特性量測。 二維結構的光子晶體波導橫向具有良好的光侷限性，垂直方向一般以傳統的 波導運用全反射的傳輸光訊號。由於其核心層極小，與光纖耦合尺寸不匹配，具 有高耦合損耗的嚴重問題。本計畫則在垂直方向改以新型的抗諧振反射式光波導 （ARROW）結構，藉由抗諧振反射，可於低折射率的介質中傳輸光訊號，具有 (1)與單模光纖尺寸及折射率匹配，(2)可製作於高折射率基片上，(3)擁有單模 低傳輸損耗等特性。本研究團隊過去十餘年在「矽基片上抗諧振反射式光波導 （ARROW）元件設計與研製」已有豐富之經驗與成果，在「二維光子晶體波導」 已有具體進展及重要成果，在「矽基片上抗諧振反射光波導結構（ARROW）光 子晶體波導」之研究也已有初步成果，另外在製程發展上，與國家奈米元件實驗 室共同合作，也有相當進展。本計畫之目的在基於過去十餘年之在矽基片上抗諧 振反射式光波導元件設計與研製之經驗與成果，結合光波段工作之光子晶體元件 結構，開發『與光纖高效率耦合之矽基片上抗諧振反射光波導(ARROW)設計的 ARROW結構光子晶體光波導波導三維元件』，完成元件設計、並進行元件研製 及特性量測。設計之元件，預期可具高傳輸特性並易與光纖高效率耦合，本計畫 並將完成該元件之基本製作與量測其基本特性，驗證設計之觀念與開發適合之製 程。本計畫之進行與完成，則在光波段工作之矽基片上光子晶體波導元件上之開 發，將是世界首創，也是重要的突破。

Photonic crystal is a kind of structure with periodic refractive index. Due to the photonic bandgap caused by the periodicity of refractive indices in the photonic crystal, light at certain frequencies could not propagate in periodic lattice caused by the Bragg’s diffraction. By introducing well-designed defect, light at certain wavelengths can be well controlled, and many planar photonic crystal waveguides have been developed. Planar photonic crystal (PPC) waveguides, have been demonstrated to have good confinement of light, in the lateral direction with a line defect in a photonic crystal structure and in the vertical direction with conventional waveguide structure. However, due to the size mismatch, there are severe problems of coupling between PPC waveguides and fibers. A new type of antiresonant reflecting optical waveguide (ARROW) has been proposed for wave confinement in the vertical direction, which utilizes antiresonant reflection instead of total internal reflection, provides the advantages of high coupling efficiency, flexible design and low transmission loss. This project is based on the long-term research experiences and accomplishments of design and fabrication of ARROW devices on Si substrates to design and fabricate ARROW-based photonic crystal waveguides on Si substrates for infrared and visible light operation. Up to now, these devices haven’t developed yet. The fabrication process will be developed by cooperation with National Nano Device Laboratories. The fabricated devices will be characterized and used to verify our design or adjust the design for optimization. Up to now, these devices haven’t developed yet by any other groups. The progress and accomplishments of this project will significantly contribute to the community in this field.