近年來，由於微機電技術的成熟，許多光電元件皆朝向微小化的方向製作，此亦有利於積體光學的發展，也就是能夠將許多光學元件整合於一半導體晶片上。可調變光衰減器即為光電元件之ㄧ。在光通訊中，它扮演了重要角色。其主要功能是用來控制或降低光訊號的強度。
本論文主要提出一可調變光衰減器之新構想：結合波導以及光纖，利用線偏振光在TM 模態下之特性，藉由入射光入射到接收端角度的不同來調控光強度。而所設計之可調變光衰減器包含:光纖槽之設計、接收端波導設計、鏡面致動的設計以及利用單模光纖與漸變折射係數光纖來設計光路。在鏡面致動部份，為了使鏡面能夠有大角度的轉動(9度)，我們設計V型熱致動器來推動鏡子。在可調變光衰減器設計完成後，接著進行光罩佈局及製程規劃。元件製程是利用微機電(MEMS)技術，並以SOI (silicon -on-insulator)晶片來實作出可調變光衰減器，最後進行元件量測。

In optical transmission systems, variable optical attenuators (VOAs) are fundamental components. They play important roles in equalizing channel intensity levels in Dense Wavelength Division Multiplexing (DWDM) systems and flattening the gain spectrum of optical amplifiers.
Variable optical attenuators based on planar lightwave circuits (PLCs) are attractive in the ability to integrate with other optical devices. A novel structure of a variable optical attenuator is proposed in this thesis. The configuration of the VOA includes a fiber groove that the single mode fiber and Grin fiber will be placed, an output waveguide, and a driven mirror with a flexible spring to fix it. The V-shape thermal actuator is designed to drive the mirror. We utilize the incident angle changes between two medium under the TM polarization to manipulate the optical power. Mask layouts and fabrications follow the device design. We use SOI (silicon -on-insulator) wafers to manufacture the VOAs by Micro-Electro-Mechanical Systems (MEMS) technology and then measure them finally.

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