本論文分為三部分研究，都是基於數位微反射鏡裝置 (Digital Micro mirror Device, DMD) 的無光罩式微影技術，精確控制紫外 (UV) 光源投射在光阻表面的劑量分布，以製作不同款式的二維及三維結構，並精確控制其形貌的精度與準確性。
第一部分利用無光罩式微影技術結合金屬蒸鍍與舉離 (Lift-off) 製程，成功於4”壓電基板上製作出中心頻率為100 MHz的剪切表面聲波 (Shear Horizontal SAW, SH-SAW) 的指叉式電極感測器 (Inter-Digital Transducer, IDT)，應用於生醫的免疫感測器快速診斷晶片與系統。此一研究挑戰的最小線寬/線距為4.185 / 4.185 μm，同時為了順利完成金屬電極的舉離製程，特別使用具反轉特性的光阻材料為光阻公司KemLab 型號KL-IR-L0 15光阻(KemLab Inc., MA, USA)。
第二部分研究針對正型光阻曝光顯影後，光阻邊緣處常出現的斜坡問題，導致後續蒸鍍金屬後舉離製程上的困難。為了改善正光阻曝光顯影後的斜坡問題，本研究將無光罩曝光機的掃描速度降低，以便於調整DMD曝光時的曝光點密度分布，得到最小的光阻斜坡寬度。模擬與實驗結果顯示，在將掃描速度降低為1/4的條件下，在最佳的優化結果可將厚0.86μm之正光阻的斜坡寬度之最大幅度可由原本的3.0 μm降低至 1.4 μm。
第三部分專注於製作高深比與圓錐狀的陣列式三維微結構，成功製作面積35×35 mm² 、週期性排列、噴嘴 (Nuzzle) 狀曲面錐形結構陣列，可應用於高效能的超音波噴孔片。此一研究首先建立數種正光阻材料的曝光顯影反應曲線，並配合數值模擬結果，精確控制投射曝光劑量的空間分佈，以獲得光阻顯影後所需特徵尺寸的三維微結構，所得到之噴嘴狀曲面圓錐結構的底部直徑104.50 μm、頂部直徑3.94 μm、高度27.45 μm。

This thesis consists of three research parts, all based on a maskless lithography system utilizing a Digital Micromirror Device (DMD), which precisely controls the ultraviolet (UV) light dose distribution projected onto the photoresist surface to fabricate various two-dimensional (2D) and three-dimensional (3D) microstructures with high shape accuracy and resolution.
In the first part, a DMD-based maskless lithography technique combined with metal evaporation and a lift-off process was used to fabricate shear-horizontal surface acoustic wave (SH-SAW), inter-digital transducer (IDT) sensors with a center frequency of 100 MHz on a 6-inch piezoelectric substrate. This device is intended for use in biomedical immunosensor rapid diagnostic systems. The design achieved a minimum linewidth/spacing of 4.185/4.185 μm. To ensure the success of the lift-off process, a reversal-type photoresist (KL-IR-L0 15, KemLab Inc., MA, USA) was used to create the necessary undercut sidewall profile.
The second part focuses on improving the sidewall slope issue that commonly occurs at the edge of positive photoresist patterns after exposure and development, which often leads to difficulties during metal lift-off. To address this, the scanning speed of the DMD-based exposure system was reduced, thereby enabling control over the exposure dot density distribution and minimizing the slope width. Simulation and experimental results showed that, under a reduced scanning speed (1/4 of the original), the slope width of a 0.86 μm-thick positive photoresist was effectively reduced from 3.0 μm to 1.4 μm.
The third part aims to fabricate high-aspect-ratio conical array microstructures. A periodic nozzle-shaped conical structure array with an area of 35 × 35 mm² was successfully fabricated, which can be applied in high-efficiency ultrasonic atomizing nozzles. Exposure-development response curves of several positive resists were established, and together with numerical simulation, the spatial distribution of UV dose was optimized to achieve the desired 3D resist profile. The resulting conical structures exhibited a base diameter of 104.50 μm, a top diameter of 3.94 μm, and a height of 27.45 μm.

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