本研究開發了以紫外光點陣列為基礎之無光罩微影技術，系統架構使用波長405 nm的紫外光，透過數位微鏡面裝置 (Digital Micromirror Device, DMD) 控制光點開關，光線通過第一鏡組成像於微透鏡陣列，並重新聚光之後通過空間濾波器，去除雜散光，接著再由第二成像鏡組將光點陣列傳遞至試片表面進行曝光。本文使用了128×96個光點陣列，實際大小為14.08×10.56 mm2，並由XYZ平台控制試片的移動；本文使用斜掃描法提高光點陣列掃描精度，利用輸入圖檔至控制板控制DMD的圖形更新，發展軟體以檢查圖形的正確性與曝光之模擬。實驗方面，選用S1813光阻，厚度為1 um，光點大小10 um，並測試簡易電路板圖形及最小圖形解析度，最終於6吋玻璃基板上曝光大面積100×50 mm2的電路圖形。實驗結果顯示所建置之無光罩曝光系統可達到最小線寬7 um，線增量2.28 um的任意不規則圖形。此外，本文也嘗試利用此一光點陣列的無光罩式曝光機進行灰階曝光與大面積3D微結構之製作。

This study develops a UV spot array oblique scanning system to perform maskless lithography patterning. A UV light source of 405 nm I wavelength is used along with a digital micromirror device (DMD) to modulate the UV light and to form array of UV spots. The UV light reflected by the DMD is projected by a projection lens into a microlens array and then focused into an array of pin-holes to filter out stray light. Finally, the spots are transmitted onto the substrate through another projection lens to expose a photoresist layer coated on a substrate. The sample is carried by an XYZ stages to perform oblique scanning lithography. The spot array size is 128x96 with an actual size of 14.08x10.056 mm2. An algorithm is developed to generate a series of images to control DMD and the exposure pattern on the substrate. A positive-tone photoresist (S1813) with a thickness of 1 um is used. The spot size of UV light is around 10 um. Finally, a PCB pattern with size of 100 by 50 mm2 is exposed and etched on a 6-inch glass substrate. The minimum linewidth is 7 um with a minimum increment of linewidth of 2.28 um. Also, this study develops an algorithm to simulate the exposure dosage by convolute the spot model with the scanning line with some modulation on the weightings of DMD. It demonstrates the possibility of using this maskless lithography system for grey-scaled UV patterning and 3D micro-fabrication.

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