近年來有鑑於高科技產業脈動之急遽變化，加速驅動量測技術與訊號傳輸及處理技術快速發展，且伴隨著台灣半導體產業之蓬勃發展，高品質、多功能的精密、線上量測技術也相對的顯得相當重要。既有的多功能精密量測系統，在系統設計與訊號分析方法上相當複雜，也犧牲了與產線之整合性；本文以此為研究動機，針對可應用於光學材料量測之橢圓偏光儀，以及可應用在精密線性平台之光學尺，分別各發展出一套光訊號調變與細分割分析方法，以期未來可應用高科技之光電製程產線之線上精密量測。
本研究發展出僅透過雙相位訊號即可分析薄膜材料之橢偏參數(Δ, Ψ)與厚度之調變式橢圓偏光量測系統，並結合共路徑外差偏光量測技術，於實驗結果中，所分析之Ψ的平均標準差為 0.13度，Δ的平均標準差為0.94度，由Ψ和Δ計算出材料厚度的平均標準差為0.55 (nm)，且可具有改變入射角度、即時測量、快速數據分析等優點。此外，亦提出可用於線性平台之多自由度精密量測系統，其中應用3D弦波線型光柵發展出訊號細分割分析方法，達到可量測精密線性平台之線性位移、垂直直線度與旋轉角度，於實驗中透過比對驗證後得知，量測得到最大誤差之線性位移、垂直直線度與旋轉角度，分別是0.239 μm、0.188 μm與 0.058度，且重複性誤差分別為±0.0215μm、±0.0295μm與±0.264度。未來希望透過本研究所發展出的方法與系統，未來期望與產業鏈結加速光電科技之發展。

In recent years, modern scientific techniques such as optical measurement, control, and automation have prospered. Furthermore, with the booming development of the semiconductor industry in Taiwan, high quality, and multi-functional precision control as well as on-line measurement techniques, have become relatively important. To get more high quality and multi-functional measurement, the system and signal analysis method are complicated. Thus, this study aims to develop novel signal modulation and subdivision technique analysis methods for modulated ellipsometer and multi-degree-of-freedom measurement. In the future, we expect the system proposed in this study to the application of on-line measures for the analysis of automatic processes as well as real-time monitoring.
At present, single-point measurement, multi-wavelength scanning, and rotating optical components are expected to acquire sample characteristic curves, which are then fitted to theoretical curves. However, the measurement steps take longer, either by spectral scanning or by continuously rotating optical components with a motor. In order to overcome these issues mentioned above, we proposed a heterodyne signals analysis method to obtain the full range of ellipsometric parameters and thickness of the single-layer isotropic thin film by use of two-phase detection precisely and straightforwardly. Also, by combining the common-path interference polarization techniques with this signal analysis method, the system can measure the ellipsometric parameters of amplitude ratio (Ψ) and phase difference (Δ) by phase detection. The experimental results show that the average standard variation of measured ellipsometric parameters (Ψ and Δ) and the thickness measurement of silica thin film deposited on silicon substrate are 0.13°, 0.94°, and 0.55 nm, respectively.
On the other hand, although measuring and specifying static/quasi-static straightness is a well-established process in existing performance standards, a standard test for characterizing dynamic straightness of single-axis linear positioning systems has not yet been developed. In order to solve this issue, we here present a novel triangular wave-based sequence signal analysis method with the advantages of simultaneously measuring linear displacements and vertical straightness errors of a linear moving air-bearing stage. An active level-triggered method was adopted for analyzing sequential triangular-wave signals to obtain a steady subdivision signal. The proposed system is similar to a linear encoder and can make online measurements of stage errors to analyze automatic processes and also be used for real-time monitoring. The performance of the proposed method and its reliability has been verified by experiments. The experiments show that the maximum error of measured rotation angle, linear displacement, and vertical straightness error is less than 0.058(degree), 0.239 μm, and 0.188 μm, respectively. The maximum repeatability error on the measurement of the rotation angle, linear displacement, and vertical straightness error is less than ±0.264(degree), ±0.0215μm, and ±0.0295 μm, respectively.

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