二維影像掃描式橢圓儀

Abstract

本文將介紹一二維影像掃描式橢圓儀，用以量測樣品的橢圓偏極參數 ( , )並推算其厚度的二維分佈。由於所使用的偵測儀為電子耦合偵測器，故能將薄膜的厚度以二維的方式呈現。 首先我們須要以入射面為參考零點校正各光學元件的偏光角。由於三個亮度橢圓偏光儀不僅可以推算橢圓偏光參數，並可反算偏光片穿透軸與入射平面偏差的方位角偏差。為了瞭解三個亮度橢圓偏光儀在二維的可行性，我們除了量測一標準薄膜橢圓偏極參數並推算薄膜之二維厚度及各點的方位角偏差。本文將提出一解決由於旋轉偏光片所造成入射角的偏差方法。 以三個亮度所量得的 (SiO2/Si) 薄膜的厚度與精密儀器中心所測之結果相近。

An Image Scanning Ellipsometer (ISE) is constructed by using the charged-coupled device as the detector. The ellipsometric parameters of a sample are measured and its two-dimension thickness is deduced. The incident plane is considered as the reference point for calibrating the azimuth angles of optical components. The three-intensity-measurement technique is used to determine the ellipsometric parameters in a polarizer-sample-analyzer photometric ellipsometer. This technique can be employed to correct the azimuthal misalignment of the polarizer or analyzer with respect to the plane of the incidence. For testing the feasibility of this three-intensity technique in two dimensions, we measure the ellipsometric parameters of a standard sample; calculate its two dimensional thickness. We also re-calculate the azimuthal deviations of each point on the sample, its result are closely related to that of our original aligned result. The measured thickness of a SiO2/Si film is compared with that of Precision Instrument Development Center (PDIC) measurement.