本論文針對一個由紫外光光源、數位微反射鏡裝置 (Digital Micromirror Device, DMD)、與投影成像鏡組組成之數位光學成像系統，提出利用CMOS影像感測器、通焦掃描量測 (Through-focus Scanning)、與影像拼接技術，將距離成像面不同高度下之各個平面上截取到所投射之DMD光點陣列的形貌與能量密度分佈，利用高斯光束 (Gaussian Beam) 的假設進行擬合。量測結果可以得知成像鏡頭的重要光學特徵，包括：場曲特徵、景深、以及光點的畸變現象。
利用量測所得出之取樣光點畸變資訊，透過單體法 (Simplex Algorithm) 的最佳化計算，推導出能夠敘述整個DMD光點分佈的畸變模型 (Distortion Model)。利用所得到的畸變模型再搭配本論文所開發的斜掃描式拆圖演算法，可以進行無光罩式的光阻曝光與曝光圖形的補正，得到更為精準且不受到畸變現象影響的曝光結果。藉由本論文所開發的光點陣列校正補償進行目標點拆圖演算法，成功在負光阻上製作出複雜的微結構圖形，包括3 μm/3 μm之線寬/間距的光柵圖型，80 μm的太陽圖，10 μm周期的同心圓。 此外還進行了8英寸和270×270 mm^2區域的大面積曝光。在大面積曝光範圍內，包括了線寬為 10 μm，圖形週期為 15 μm的正方圖形陣列；直徑為 7.5 μm，圖形週期為 12.5 μm的圓形陣列；線寬/線距為 100 μm/100 μm 的微流道；線寬/線距為 10 μm/10 μm的對位靶標結構。

This dissertation proposes a method to accurately determine the coordinates of arrayed ultraviolet (UV) spots which are projected from a digital micromirror device (DMD) through an image projection lens. Each projected UV spot can be modeled mathematically as a Gaussian beam and its optical intensity distribution is measured using a through-focus scanning (TFS) and image stitching (IS) method. The measured Gaussian beam characteristics of the projected array of UV spots provides important information on the DMD-based optical system such as optical distortion, field curvature, and depth of focus. These measured optical characteristics are critical and essential for constructing a DMD-based maskless lithography system.
Based on the measured distortion information, a distortion model is derived based on the Simplex optimization algorithm. This derived distortion model is then combined with UV patterning algorithms to generate DMD binary images for maskless UV exposure on a photoresist (PR) layer deposited in a substrate. Through exposure experiments, arbitrary patterns were successfully fabricated, including linear gratings with linewidth/spacing of 3μm/3μm, an 80μm sunburst pattern, and concentric circles with a period of 10 μm. Large-area exposures of an 8-inch substrate covering a 270×270 mm² area was also performed. These exposures included square arrays with a linewidth of 10 μm and a period of 15 μm, circular arrays with a diameter of 7.5 μm and a period of 12.5 μm, microchannels with a linewidth-spacing of 100 μm/100 μm, and alignment target structures with a linewidth-spacing of 10 μm/10 μm.

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