本研究建構一套利用紫外光點陣列掃描的曝光系統以取代以光罩(photomask)為基礎的黃光微影技術，無論是二值光罩式(binary)或是多灰階光罩式(grayscale)的微影製程都可以透過本研究的曝光系統來完成。無光罩式曝光系統的優勢在於曝光圖形的設計與製作完全數位化，少了實體光罩的製作成本與時間，讓曝光變得快速且彈性，使無光罩式曝光系統擁有極大的靈活性。
本論文之無光罩曝光系統的主要架構是由數位光調製技術裝置(Digital Light Process, DLP)、雙光學投影鏡頭、及自行研製的微透鏡與空間濾波器陣列(Micro-Lens and Spatial Filter Array, MLSFA)來完成。在本文中不僅完成紫外光點陣列斜掃描式系統的硬體建置，也包含2D與3D曝光圖形的演算法開發完成。本系統中使用波長405 nm之紫外光源，透過數位微反射鏡裝置(Digital Micromirror Device, DMD)控制每顆在試片表面上光點的開關及劑量；光束經由光學成像系統濾波並成像2D光點陣列於試片表面。陣列大小為124 92，涵蓋面積約為14 10.5 mm2，待曝光的光阻試片則由XYZ平台控制試片移動。利用演算後的圖檔輸入至控制板，DMD晶片搭配位移平台控制在不同的位置上產生預期的圖案。最後，二維圖形結果的部分以厚度2 μm的正光阻S1813來完成大面積50 100 mm2之電路圖形，最小線寬約10 μm左右，另外，厚度4的負光阻AZ P2070則用於完成對角線6.2吋大面積之20 μm直徑圓柱形(pillar)導光板結構。最後，本論文並提出以此無光罩式曝光系統製作三維結構圖形，其曝光結果部份有五種，(1). 以正光阻AZ P4562完成60 60 mm2面積之方狀楔形(ramp)導光板結構，其結構高度4 μm，特徵尺寸90 μm；(2). 250μm週期的同心圓弦波狀(sine wave)，其面積為10 mm2，結構高度6 μm；(3). 菲涅耳透鏡(Fresnel lens)狀，其直徑為2 mm，結構高度4 μm；(4). 螺旋(helicoid)狀，其直徑為1 mm，結構高度4 μm；及(5). 八卦圖(Bagua)狀，其直徑為2 mm，結構高度4 μm等。由上述的任意結構之曝光結果驗證本研究的無光罩曝光系統於2D及3D等曝光之能力。

This dissertation constructs an unconventional exposure system for two- or three-dimension photolithography so that a binary or grayscale photomask is no longer needed. This maskless lithography system is base on a projected UV light spot array with the oblique scanning method. It demonstrates the advantages that exempt the producing time and cost of the physical photomask because of the digitization of mask pattern. A faster and flexible of produced abilities in the maskless lithography system is robust.
The constructed system consists of a UV light source, a digital micromirror device (DMD) clever opted in digital light process (DLP) technique, a microlens/pinhole array, two optical projection lenses, and a three-axis (XYZ) servo-controlled stage. The optical system can form a rectangular array of UV spots with a diameter of a few m directly on the surface of a sample sitting on the stage. A photoresist (PR) layer is coated on the sample surface. This UV exposure system can expose the whole area of the PR layer in a maskless manner by using an oblique scanning approach. Since the corresponding group of micromirrors can independently modulate the energy intensity of each UV spot in the DMD, a three-dimensional (3D) UV dosage distribution can be achieved through computer programming on the DMD and the XYZ stage. After PR developing processes, 3D PR microstructures with arbitrary patterns and/or surface profiles can be readily formed by this maskless lithography system. Afterward, the AZ4562 photoresist layer on the glass plate presents the five exposure results as (1). a lot of ramp structures are made for front light guide application, and each ramp dimension is around 90 μm2, depth is around 4 μm; (2). a 250 μm period of sine wave concentric circle structure, the pattern size is around 10 mm2 and the depth is around 6 μm; (3). a Fresnel lens-like of structure, each pattern diameter is around 2 mm and the depth is around 4 μm; (4). a helicoid structure, each pattern diameter is around 1 mm and the depth is around 4 μm; as well as (5). The Bagua map structure, each pattern diameter is around 2 mm and the depth is around 4 μm. Those experimental results as 2D and 3D microfabrication that show the maskless system in this dissertation address the arbitrary patterns successfully.

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