本論文的研究主題是如何在一光阻 (Photoresist, PR) 層上以曝光與顯影的方式製作出大面積的三維微結構，方法是使用一種以數位微反射鏡裝置 (Digital Micro-mirror Device, DMD) 為基礎的無光罩式微影技術，可以精準調控投射在光阻層上的紫外光劑量。該系統搭配光點陣列的斜掃描以及紫外光源的閃爍，利用所開發之跳躍式斜掃描演算法 (Obliquely Scanning and Step Strobe-lighting , OS3L)，針對任意表面形貌之獨立三維微結構建立一套數值迭代模擬演算法，以求得正確的曝光劑量。另外，針對高填充率之週期性三維微結構，則是使用反卷積 (Deconvolution) 的數學計算求得正確的曝光劑量分佈。
在實驗方面，首先建立數種正光阻材料的曝光顯影反應曲線，以搭配數值模擬的結果，求得曝光粒子密度分佈，與最佳的實驗製程參數。同時結合低差異數列 (Low-Discrepancy Sequences) 之Halton序列分佈法，依照給定的解析度將曝光粒子密度在單位面積內均勻地實現，避免發生叢聚 (Cluster) 而導致實際曝光發生結構變形現象。有了該紫外光圖案化方法後，就能夠精準控制投射曝光劑量的空間分佈，從而在光阻顯影後獲得所需特徵尺寸的三維微結構。
針對大面積曝光所產生之拼接縫 (Stitching Error) ，本研究亦提出一種基於相鄰掃描道重疊的滲透技術。透過量化分析結果，證明該方法能夠有效抑制拼接縫產生。本研究成功在曝光面積為 200x160 mm2的正光阻上，製作出軸對稱/非軸對稱之三維微結構。並在正光阻上製作面積為35x30 mm2 和20x20 mm2的週期性三維微結構，同時結合熱回流技術 (Thermal Reflow) 大幅降低微結構陣列表面之粗糙度，能夠應用於光學元件或製造鎳模具供大規模生產背光顯示的導光板。

This study proposes a maskless lithography technology based on Digital Micromirror Device (DMD) to perform large-area and three-dimensional (3D) microstructure fabrication on a photoresist (PR) layer. This system along with an obliquely scanning and step strobe lighting (OS3L) algorithm developed earlier to precisely control the distribution of ultraviolet (UV) dose projected on the PR layer. For each individual 3D microstructure with an arbitrary surface topography, a numerical iterative simulation algorithm is developed to determine the optimal distribution of UV dose. As for periodic 3D microstructures, the UV dose distribution is determined mathematically from deconvolution calculation.
In experiments, the characteristic curves of several positive and negative types of PRs are quantitatively determined. These information are used to optimize the experiment parameters and the density distribution of UV exposing points based on numerical simulation. The Halton sequence distribution method of low-discrepancy sequences is adopted to discretize the density distribution of UV exposing points with a given resolution, so that the UV exposing points can be evenly distributed within a unit area. With the UV patterning method, the spatial distribution of the projection exposure dose can be precisely controlled, so that three-dimensional microstructures with the required characteristics and surface profiles can be obtained after the photoresist is developed.
Aiming at the stitching error caused by large-area exposure, this study also proposes a gradient dither method based on the overlapping of adjacent scanning slices. Through experimental testing, it is proved that this method can effectively suppress the stitching error. This study successfully fabricated axisymmetric/non-axisymmetric three-dimensional microstructure on a positive photoresist with an exposure area of 200x160 mm2. Additionally, we fabricated periodic three-dimensional microstructures on a positive photoresist with an area of 35x30 mm2 and 20x20 mm2, and combined thermal reflow to greatly reduce the roughness of the microstructure array surface. It can be used for optical components or to fabricate nickel molds for the mass production of light guide plates for backlight displays.

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