以伽瑪光照射及質子交換濕式蝕刻法研製脊形鈮酸鋰光波導

Fabrication of Gamma-Ray Irradiated Lithium Niobate Ridge Optical Waveguides Using Proton-Exchange Wet-Etching

張家豪(Chia-Hao Chang)

指導教授 ： 王維新

國立臺灣大學/電機資訊學院/電子工程學研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.10732

摘要

本論文以伽瑪射線照射鈮酸鋰基板，再利用質子交換溼式蝕刻法製作脊形光波導。並針對其蝕刻深度、質子交換的氫離子濃度、脊形結構之外觀比等進行研究與討論
在製程方面，嘗試不同的質子交換酸源和時間，並用氫氟酸與硝酸的混合液進行濕式蝕刻，以製作出脊形結構。在量測方面則利用掃描式電子顯微鏡與原子力顯微鏡分別量測脊形的外觀比與表面粗糙度；之後再以二次離子質譜儀量測氫離子的濃度分佈。實驗數據顯示本研究方法可得到較佳的脊形結構，且適用於製作脊形光波導。
最後，再以本研究方法製作脊形結構之Ｓ形彎曲波導，並量測其傳輸率。量測結果顯示傳輸率上升，此對積體光波導侷限性的改善極有助益。

關鍵字

伽瑪射線 ； 質子交換 ； 溼式蝕刻法 ； 脊形結構 ； 傳輸率

並列摘要

In this thesis, ridge waveguides are successfully fabricated by using proton exchange wet etching in gamma ray irradiated lithium niobate (LiNbO3). In particular, the etched depths, hydrogen ion concentrations, and the aspect ratios of ridge structures are emphasized.
For testing, the proton exchanged areas are obtained by using various acid sources for different times, and then the exchanged areas are wet etched with a mixture of hydrofluoric acid and nitric acid to reveal ridge structures for optical waveguides. The aspect ratio and the surface roughness are measured by using scanning electron microscopy and atomic force microscopy, respectively. Secondary ion mass spectrometer is then used to explore the hydrogen ion concentration. Experimental results show the proposed method can be successfully used to fabricate better ridge structures for optical waveguides.
Moreover, the proposed method is used to fabricate an S-bend ridge waveguide structure. The measured transmission efficiencies show optical waves can be more confined, which is advantageous for the improvement of integrated optical waveguides.

並列關鍵字

gamma ray ； proton exchange ； wet etching ； ridge structure ； transmission

參考文獻

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