絕緣層覆矽全光微環調製器之製作與量測

Fabrication and Measurement of All-Optical Micro-Ring Modulators on a Silicon-on-Insulator Substrate

王舜能(Shun-Neng Wang)

指導教授 ： 毛明華

國立臺灣大學/電機資訊學院/電子工程學研究所/碩士(2015年)

https://doi.org/10.6342/NTU.2015.01272

摘要

在本論文中，我們製作了全光微環光開關，利用理論分析與數值模擬輔助設計元件並以製程技術實現，在絕緣層覆矽的基板上完成了一個以光學調控的光開關，並與一波導耦合的結構。由於尺寸的因素對元件影響層面相當廣，為求精細，我們利用電子束微影系統以及乾式蝕刻等製程輔助製作。
　　在本實驗中，我們主要使用光纖─波導耦合作為主架構進元件的量測與特性的探討。從量測到的頻譜中，我們可以從穿透強度的變化
驗證微環共振腔與波導相互耦合的現象。因為模態有高的品質因子，故只要少量的波長平移即可大幅改變穿透量。我們利用共振腔吸收激發光的能量後產生的載子濃度變化，造成的對應的折射率變化（Carrier-induced refractive index change），來調變特定波長的穿透之特性。
　　我們驗證了矽可以作為光開關或作為一調製器，藉由激發─探測法證實了載子生命期可短至305皮秒，高品質因子也讓我們的元件只需要少量的折射率變化即可造成穿透強度的變化；因其材料與結構單純，易於與其他電路互相整合。

關鍵字

微環 ； 光學開關 ； 製程 ； SOI ； 載子生命期 ； 品質因子

並列摘要

In this thesis, we design all-optical switches based on theoretical analysis and numerical simulations, and then fabricate such devices. All structures are fabricated on a silicon-on-insulator substrate, and each of our devices is coupled to a tapered waveguide. Due to the significant influence of the structure variation, we use techniques such as e-beam lithography and reactive ion etch in order to define the structure size more precisely.

In our experiment, we mainly use waveguide-fiber coupled structures to measure and characterize our devices. We could verify the coupling phenomenon by the transmission spectrum. Due to high quality factor, we can greatly change light transmission by very little wavelength shift. This is due to the property of carrier-induced refractive index changing to modulate the transmittance of some certain wavelength.

We verify that silicon can serve as material for an optical switch or modulator by pump-probe transmission measurement. The carrier lifetime in the resonator can be as short as 305ps, and the high quality factor makes it easier to modulate the transmitted intensity by a little amount of wavelength shift. The advantages of these devicesare their relative simple structures and high compatibility for integration.

並列關鍵字

microring ； optical switches ； fabrications ； Silicon on insulator ； carrier lifetime ； quality factor

參考文獻

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