絕緣層上矽微環共振腔與波導耦合之製作與分析

Fabrication and Analysis of Microrings and Waveguide Coupling on Silicon-on-Insulator Substrate

蔡明倫(Ming-Lung Tsai)

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(2014年)

https://doi.org/10.6342/NTU.2014.02148

摘要

基於本實驗室過去在製作微碟共振腔的經驗，本論文嘗試製作微環共振腔與波導耦合之結構，並使用絕緣層上矽基板。最終我們成功製作了微環共振腔與波導耦合之結構，並形成迴音廊模態且品值因子值達到9600。
在元件製程上遇到兩個問題，其一為在文獻多使用感應耦合電漿活性離子蝕刻機製作絕緣層上矽元件，而本所此機台並無配置可蝕刻矽材料的氣體；其二為電子束顯影曝光不足造成的缺口問題，最終我們都藉著參考文獻與進行測試成功的解決。
在波導與微環共振腔耦合的實驗量測，藉著自由頻譜範圍與微環直徑成反比的驗證，得到我們製造的結構成功耦合形成迴音廊模態，且品質因子值與直徑的關係也符合我們的預期。最後在元件應用的部分，以變溫和照光兩種方法進行測試。變溫實驗成功獲得波長的紅移，矽的熱光矽數也與文獻上的數值一致。照射綠光雷射實驗的結果雖然與預期不符，但以載子與熱對等效折射率的關係去推導，我們也找到了造成此現象的原因，證明了以綠光雷射照射的方式只能產生紅移的現象。

關鍵字

絕緣層上矽 ； 微環

並列摘要

Based on our laboratory’s successful fabrication of microdisk resornators, we try to fabricate microring resornators and waveguide coupling structure on silicon-on-insulator substrate in this thesis. At the end, we have successfully fabricated such resornators and coupling structure with max quality factor 9600 from whispering gallery modes (WGM) in microring resornators.
There are two problems encountered in our device fabrication .First, ICPRIE is usually used to fabricate SOI device during etching, while there is no Fluorine in our facility. Second, there are unwanted holes appearing due to under-exposure in the e-beam lithography. These two problems had been solved by referring to the literature and carrying out systematic tests.
In coupling experiments, we got the FSR of a 10um microring is twice that of a 20um microring, so we can conclude that the coupling with waveguide and microring was successful and there are WGMs in microring resonators. The relation between quality factor and the microring diameter is also consistent to our expectations. Finally, for the application of our devices, we test temperature variation and optical excitation. We observed the redshift phenomenon by increasing the temperature and got the thermo-optic coefficient almost the same as those in the literature. In optical excitation by a green laser, we observed an unexpected phenomenon. Referring to the temperature-induced refractive index change and the carrier-induced refractive index change, we prove that only red shift will be observed under such optical excitation condition.

並列關鍵字

SOI ； MICRORING

參考文獻

[1] Wu, Qi, Jeremiah P. Turpin, and Douglas H. Werner. "Integrated photonic systems based on transformation optics enabled gradient index devices." Light: Science & Applications 1.11,2012

[2] Bruel, M. "Silicon on insulator material technology." Electronics letters 31.14,1995

[3] Colinge, Jean-Pierre, and J. Colinge. Silicon-on-insulator technology: materials to VLSI. Vol. 3. Dordrecht, the Netherlands: Kluwer Academic Publishers, 2004.

[5] Okamoto, Katsunari. Fundamentals of optical waveguides. Academic press, 2010.

[6] J. Heebner, R. Grover, T. Ibrahim, Optical Microresonators: Theory, Fabrication and Applications, Springer (2008)