摘要
　　本文研究雷射光分佈變化對於高分子材料(Polymethy-methacrylate, PMMA, Polyimide, PI)細微加工的影響，在此考慮三種影響光分佈的情形：(一) 工件與雷射光束傾斜，(二) 光路增加透鏡，(三) 將工件置於聚焦面外。
在此利用不同角度楔型塊，將工件(PMMA)放置其上，使工件與入射光傾斜，實驗結果顯示：燒蝕率在各種能量密度下，隨著雷射光入射角度增加而減少，此外燒蝕的孔深將會隨著工件隨聚焦面的距離增加而減少。
　　由實驗結果可得：在光路上增加透鏡則將改變雷射光投射面積，且雷射能量密度變化、對工件(PI)的燒蝕深度亦有所不同。此外本文利用傅立葉光學求出光在空間中的分佈，計算局部燒蝕率，進而轉換成預測的燒蝕截面。
　　最後，成像面與聚焦面之間的距離亦會改變光分佈，由模擬結果而知當成像面離聚焦面越遠，燒蝕截面將逐漸成為U形，而壁面與底部將出現規律的凹凸，其原因應是能量密度已不再均勻。

Abstract
　　The purpose of this research is to examine the influence of excimer laser illumination on micromachining. Here are three different kinds of condition that influence light distribution. First, the incline of work piece and the laser beam indicates that the ablation rate decreases with the increase of incident angle for various influences. Beside, the depth of a hole in the samples oblique to the laser beam at a distance from the focal plane decreases with the increase of the distance from the focal plane. Second, to increase the lens on the path of rays will change the light projection area. According to the situation, the change of energy density causes the change of ablation rate. In this case, it will present the experimental and simulation results. The theory of the model can divide into two steps. In the beginning, the local distribution of the light over the developing structure is evaluated for each pulse by using Fourier optics. Then, the local distribution is used to calculate the local etch rate, and hence the change to structure. Finally, the defocus of the laser beam changes the local light distribution. When the degree of the defocus increases, the beam’s intensity becomes not uniform. The result of simulation shows that the defocus increases, then the structure becomes U-grooves.

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