有別於傳統的減法製造，積層製造技術 (Additive manufacturing, AM) 是將材料以逐一堆疊的方式形成三維物件的加法製程，也被稱為3D列印技術。隨著3D列印技術在近年來的蓬勃發展，憑藉對複雜結構可以快速製造之優勢，逐漸取代成本高昂且時間長的減法製造。而3D列技術當中光固化成型技術 (Vat Photopolymerization, VP) 具有最佳的列印解析度，目前已普遍商業化的列印技術有立體光刻成型 (Stereo Lithography Appearance, SLA)及數位光固化處理 (Digital Light Processing , DLP)，一般商用列印機的解析度在20至100 μm，要達到奈米尺度的列印解析度需要使用雙光子聚合技術 (Two-photon polymerization, TPP)，但其價格昂貴因此無法被廣泛運用，因此本研究著重於將提升成本較低的SLA或DLP之解析度，以應用於微製造製程。
本研究以DLP技術做為基礎，與合作廠商協議打造出可調焦距式的光固化3D列印機，而般市售DLP列印機的投影機焦距多為固定，DLP的列印解析度是由光源的投影設備之最小像素點所決定，透過調整投影焦距可以將列印解析度從100 μm提升5 μm。並利用高解析度的優勢將DLP光固化技術應用於原子力顯微鏡 (Atomic Force Microscope, AFM) 的探針製程開發。透過設計不同懸臂樑長度、位置及列印層厚比較應用於AFM所得到的共振頻率、品質因子及反射訊號，並設計四種切層影像列印出針頭以利後續掃描表面形貌。製程方面，透過調整成型平台的抬升速度，改善探針表面在列印過程中產生的氣泡，避免氣泡存在影響探針整體機械強度。另一方面，吾人發現在列印厚度為5 μm之懸臂樑使用任何曝光秒數皆無法成功印製，透過增加曝光面積及密度能夠改善，後續要將懸臂樑厚度縮減可以透過在周圍增設支撐結構來增加曝光面積。最後，再列印過程中發現環境濕度對列印品質會造成影響，於高濕度環境下會使光敏樹脂吸收水氣膨脹，導致列印出懸臂樑變厚而無法進行共振。
將以Pt做為反射層之光固化探針實際於AFM進行測試，根據反射訊號強度的測試結果，光固化探針能夠達到一般商用探針的0.1-0.2倍，而約有五成的探針能夠共成功獲得共振頻率及品質因子，並比較列印出的懸臂樑厚度與兩者的關係，結果顯示並無明顯趨勢，日後續要進行更嚴謹的參數設計進行進一步的確認。最後以光固化製作之樣品進行表面形貌掃描，確認光固化探針的實用性，並成功掃描出陣列結構明顯的影像。

Additive manufacturing (AM) is also called 3D printing, which builds three-dimensional objects by depositing layer-upon-layer materials. And vat photopolymerization (VP) is one classification of 3D printing, which has the highest resolution and excellent surface quality. Stereo lithography appearance (SLA) and digital light processing (DLP) are the most common techniques of VP in the market and their resolution can achieve 20 to 100 μm. However, the resolution is still not enough to manufacture the micro or nanostructures. Only the two-photon polymerization (TPP) technique is effective for the fabrication of 3-D structures having a resolution of 100 nm or better. But TPP is not widely applied in MEMs because of its high cost. Here we introduce the low-cost DLP 3D printer with a higher resolution to 5 μm to develop the fabrication of AFM probe. The traditional AFM probe used MEMs fabrication is time-consuming and relatively high-cost. This study will use the customized DLP printer to manufacture the AFM probe and applied in AFM topography scanning. After adjusting the resolution, printing direction, peel-off speed, and curing time, we successfully manufacture the DLP-printed probe. The reflection signal of the DLP-printed probe is 0.1 to 0.2 V, which is around 0.1 times of the commercial probe. The DLP-printed probe can be vibrated with a yield of about 50 % and the resonant frequency and quality factor are in the range of 25 to 75 kHz and 15 to 100, respectively. The result of scanning the structure of the square array shows that the DLP-printed probe can be properly used in AFM topography scanning.

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