以矽基板製作矽微碟共振腔及與氮化矽波導垂直耦合之研究

Fabrication of Silicon Microdisk Resonators Vertically Coupled with Silicon Nitride Waveguides

徐開邦(Kai-Bang Hsu)

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(2018年)

https://doi.org/10.6342/NTU201803110

摘要

我們以(100)矽基板製作矽微碟共振腔，利用平坦化製程與氮化矽波導整合。以中心波長1330nm之寬頻光源SLD (Super Luminescent Diode)經由單模的透鏡光纖打入波導，並由另外一端收光做傳輸頻譜(transmission)的分析，驗證微碟共振腔與上方波導的共振特性及確定迴音廊模態位置。
由光罩的設計我們可以製作出不同水平距離的微碟共振腔及波導之元件，經由量測傳輸頻譜來分析耦合程度的差異。另外我們也利用COMSOL模擬軟體來分析、辨認頻譜上的迴音廊模態。由於微碟及波導的相對尺寸關係，我們的波導相當於是寬波導，並且垂直式耦合容易產生高階模態，因此在模擬時除了TE一階模態也考慮二階及三階模態的情況。
我們也會就目前製程遇到的問題，如微碟尺寸太小，因此做進一步的量測會有困難，以及垂直耦合的間距無法直接觀察，未來應重新設計光罩，做尺寸較大的微碟以探討更細微的問題。

關鍵字

微碟共振腔 ； 濕式氧化 ； 光學量測

並列摘要

We fabricated silicon microdisk resonators on a (100) silicon substrate and integrated them with silicon nitride waveguides using a planarization process. We used the single-mode lens fiber coupling method for the transmission measurement with a super luminescent diode as the light source whose center wavelength is 1330nm. We can verified the resonance properties of the fabricated microdisks and the upper waveguides to determine the characteristic modal structure of whispering gallery modes.
By the design of the photo mask, we can make microdisk resonators and waveguides devices with different horizontal distances. In addition, We also use the COMSOL simulation software to analyze and identify the whispering gallery modes on the spectra. Due to the resolution limit of photolithography, our waveguides are relatively wide waveguides. Furthermore, the vertical coupling is easier to produce high-order modes, so in the simulation, besides the TE fundamental mode, the second-order and third-order modes are also considered.
We will also discuss difficulties in the current process we have encountered, such as the microdisk size is too small, it will be difficult to make further measurements, and the vertical coupling spacing cannot be directly observed. In the future, the photo mask should be redesigned to make larger microdisks to explore more advanced problems.

並列關鍵字

Microdisk resonators ； Wet oxidation ； Optical measurement

參考文獻

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