量測非均向光學薄膜之反射偏極態與應用

The polarization states reflected from an anisotropic thin film : measurement and application

陳詠勳(Yung-Hsun Chen)

指導教授 ： 任貽均

國立臺北科技大學/電資學院/光電工程系研究所/碩士(2008年)

https://doi.org/10.6841/NTUT.2008.00011

摘要

研究非均向光學薄膜之光學特性，製程上將基板傾斜沈積，可蒸鍍出具有雙折射現象的微觀柱狀結構。量測上提供一個固定入射角的量測方法，藉由稜鏡與
基板耦合，改變入射平面與沈積平面夾角，可增強偏極轉換的反射率。旋轉偏光片(polarizer)改變入射光的線偏極態，反射端則利用旋轉析光片(analyzer)來觀察偏極態的變化，並量測出橢圓參數。因而可利用薄膜的厚度、柱狀傾角、三軸折射率對橢圓參數的靈敏度分析，來優化薄膜的光學常數。
實驗上，以氟化鎂與二氧化矽作為蒸鍍材料，將基板傾斜沈積，其中二氧化矽以電子槍的方式製程，氟化鎂則以物理氣相沉積的方式，應用上，藉由旋轉沉積平面角與改變入射線偏極態，觀察反射偏極態的變化，並討論橢圓率e與橢圓倾角θ可調制的最大範圍。氟化鎂則以熱阻舟蒸鍍方式。

關鍵字

非均向薄膜 ； 光學常數 ； 光學特性

並列摘要

The optical properties of anisotropic thin films have been investigated. The tilted-columnar birefringence thin films were prepared by oblique angle deposition method. When the incident angle of light fixes at the certain angle, the polarization
conversion reflectance(PCR) is enhanced by the prism coupling effect and rotating the deposition plane in the prism couple system. The polarization state of the reflected light can be observed for any polarization state of incident light in the rotating analyzer ellipsometry system. The optical constants of an anisotropic film such as the thickness, tilted angle and principle index are determined by fitting the curve of ellipse parameters.
In the experiment, SiO2 and MgF2 as columnar thin films are fabricated in the E-Beam and thermal evaporation system, respectively. The variety of polarization states of the reflected ray is simulated by turning the deposition plane and the transmitted direction of polarizer.

並列關鍵字

Optical thin film ； Optical characteristic ； Optical constants

參考文獻

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