以量測反射係術探測光學薄膜之特性

Optical thin film characterization via the measurement of reflection coefficient

余季欣(Ji-shin Yu)

指導教授 ： 李正中

國立中央大學/理學院/光電科學與工程學系/碩士(2014年)

摘要

本文分為兩部分，在模擬部分我們模擬了高低折射率材料的反射光譜及反射相位，比較了使用反射光譜和反射係數去擬合光學常數的準確性，成功的證明藉由量測反射係數可提高基因演算法在計算上的準確性。在實驗部分我們藉由掃描式白光干涉儀量測光學膜的干涉條紋，再經由傅利葉轉換求得反射振幅及反射相位，在量測上我們比較量測樣品四個不同區域的結果，確定實驗上的穩定性，接著利用兩者資訊搭配基因演算法擬合出折射率和厚度，實驗的結果和橢偏儀做比較，其計算結果和橢偏儀相近，証明了此實驗方法的可行性。

關鍵字

反射係數 ； 光學薄膜

並列摘要

The thesis consists two parts. In first part, the reflection amplitude and reflection phase of high and low refractive index material are simulated. The accuracy of using reflectance and reflection coefficient to calculate optical constant are compared. It proves that using reflection coefficient can improve the accuracy. In the second part, we measure the interferogram of thin film by using white light scanning interferometer. The reflection amplitude and phase are calculated by transforming the interference information. In order to confirm the stability of our method, we measure four different parts of the sample. And then, we use reflection coefficient and genetic algorithms to fit the optical thickness and refractive index. The measure results are close to that measured by ellipsometry. It indicates our method is feasible.

並列關鍵字

reflection coefficient ； optical thin film

參考文獻

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