奈米級干涉式材料表面形貌及薄膜量測系統

Nanoscale Interferometric Measurement System for Material-Surface Profiles and Thin Films

賴政忠(Cheng-Chung Lai)

指導教授 ： 許怡仁

中原大學/理學院/應用物理研究所/碩士(2006年)

https://doi.org/10.6840/CYCU.2006.00445

摘要

在本研究中，我們提出並建立一套可達奈米解析度的表面形貌及薄膜量測系統。系統主體為基於雙干涉儀的概念所架構而成，其中用作相位補償的子系統之作用為在系統當中作光延遲的參考端，由於壓電換能器在連續振盪間起始點的偏差，使得在樣品的量測過程當中，需有一相位補償的機制。在表面形貌量測的應用裡，材料表面形貌的資訊來自解析干涉訊號的相移，經由前述的相位補償機制，系統的軸向解析度可達1.09 nm。在薄膜量測的應用上，光束以45°的偏振態斜向入射於樣品表面，在此設計之下，系統可同時作薄膜折射率及厚度的量測。在分別測得TE與TM兩種模態的干涉訊號之後，經由兩組干涉訊號的相移和強度比即可計算出薄膜的折射率與厚度。

關鍵字

薄膜 ； 厚度 ； 折射率 ； 相移 ； 表面形貌 ； 干涉儀

並列摘要

We proposed and developed a low-cost system for profilometry and thin film measurement at nanometer resolution. The system is based on the concept of a dual interferometer. The sample was measured while a simultaneous compensation of the phase deviation due to the instability of piezoelectric transducer served as an optical delay component was performed. In the application of profilometry, the information of the surface profile of a material was obtained from the phase shift of the interference signal. By using the proposed compensation mechanism, an axial resolution of 1.09 nm was achieved. For the measurement of a thin film or membrane, the probe beam was prepared to polarize at 45° and was oblique incident on the sample. The system can perform a simultaneous measurement of the refractive index and the geometrical thickness as well as the position when the thin film is suspended. In order to calculate the refractive index and thickness of the thin film, the phase shifts and intensities of the interferograms of TE and TM waves were measured independently. By comparing the ratio of intensities and the phase shifts of the interferograms, the refractive index and the thickness of the thin film can then be obtained simultaneously.

並列關鍵字

phase shift ； profilometry ； thin film ； interferometer ； thickness ； refractive index

參考文獻

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