黃光製程係使用滾輪或狹縫式噴嘴，將感光劑塗佈在基板上，再使用曝光機將光罩上的圖形印到感光劑，當感光劑與UV光反應後，再經由顯影製程，使用顯影液將未反應的區域去除，留下所需要的圖形，最終用烘烤機將感光劑定型，就是一道黃光製程的流程，也是一道製程的結構。
黃光製程需考慮製程的均勻性，均勻性是看材料在基板上的最大/最小厚度或寬度分佈情形，當分佈不均時，會影響後製程的堆疊，造成組裝精度變差的問題，所以對於製程均勻性的要求，會選擇相對應的機台生產。而使用滾輪塗佈的方式，會因為滾輪或基板表面不平整，感光劑沾上後，塗佈在基板上就會均勻性不佳；狹縫式塗佈機，靠泵浦加壓到噴嘴，再擠到基板上，只要噴嘴的吐出壓力穩定時，就會有良好的均勻性。
本次研究塗佈噴嘴的潔淨度，潔淨度除了會影響均勻性外，還會影響到產品品質。噴嘴在塗佈時，感光劑會在噴嘴產生毛細現象，當塗佈後表面、側面有殘餘感光劑，會造成表面感光劑固化、硬化，造成噴嘴內部堵塞或掉落在基板，形成不良缺陷，最終增加公司的營運成本，所以每次塗佈後，會清潔噴嘴表面，維持表面的潔淨度，降低下次生產時的缺陷掉落及不良品產生。
噴嘴的清潔方式，通常有負壓抽氣與物理清潔法。抽氣是塗佈後的噴嘴，在負壓下，將表面感光劑快速抽掉；而物理清潔是使用刮刀，在塗佈後將噴嘴表面的感光劑刮除。此次研究噴嘴在清潔的過程，什麼動作會影響表面的潔淨度，並利用Ansys繪製模型及模擬刮刀清潔時的動作，模擬中找出材料的使用條件，並利用產品做實驗，將條件代入田口實驗設計，並收集測試後的結果，分析結果的S/N比，然後代入Mini-tab分析資料分佈與最有顯著關係的因子，並討論影響潔淨度機制。
本次研究因子造成的影響原因，當刮刀壓入量在降伏應力區間時S/N比最高，Ansys的模擬可看出刮刀最貼合Nozzle、應力-應變較穩定，為最佳的清潔Nozzle條件；當刮刀在彈性區間，會因為刮刀與噴嘴的貼合性不好，造成噴嘴表面會清潔不淨；當接近極限應力，會因為刮刀變形過大及材料已進入頸縮階段，會產生刮不乾淨或材料提前劣化的狀況。而刮刀移動速度越慢，會降低刮刀與噴嘴移動時的摩擦力，所以才能提升Nozzle表面潔淨度，但刮刀移動速度的數據，非常態性分配，會影響數據分析，所以此次僅參考改善數據。

The Photo process involves the precise application of photoresist to a substrate using roller-type or slit-type nozzles, followed by exposure to a photomask and subsequent development. The resulting pattern is crucial for the manufacturing process. However, achieving uniformity in the process is imperative to prevent adverse effects on downstream processes, such as decreased assembly precision. This research focuses on the Photo process, specifically examining the impact of coating nozzle cleanliness on uniformity and product quality.
The coating method, whether using a roller-type or a slit-type nozzle, plays a vital role in determining uniformity. Uneven surfaces, typical in roller or substrate topography, can lead to poor coating uniformity. In contrast, the slit-coating use the pump to pressurize the photoresist and ensure stable compression pressure to have better uniformity.
This study delves into the cleanliness of coating nozzles, recognizing its critical influence on both process uniformity and final product quality. Capillary action during coating may result in residual photoresist on the nozzle's surface, leading to defects and increased operational costs. Pre-coating cleaning procedures are essential to maintaining cleanliness and reducing the defects in subsequent production runs.
Two primary cleaning methods, Exhausting pressure, or physical cleaning. Exhausting pressure involves rapidly removing surface photoresist under high pressure, while physical cleaning employs a pad to remove residual photoresist. The study explores the impact of these cleaning methods on nozzle cleanliness.
Ansys is utilized to model and simulate the scraping action, determining optimal material usage conditions. Experimental trials are conducted, and the Taguchi experimental design is employed to collect and analyze data, with a focus on the signal-to-noise ratio (S/N). The influential factors are identified using Mini-tab, providing insights into the mechanisms affecting cleanliness.
This study investigates the factors influencing the performance of a pad in the cleaning process. The Signal-to-Noise (S/N) ratio is highest when the pad penetration is within the yield stress area. Ansys simulations reveal that optimal cleaning conditions for the nozzle are achieved when the pad closely fits the nozzle, resulting in stable stress-strain behavior. However, in the elastic deformation area, poor fit between the pad and nozzle leads to ineffective cleaning of the nozzle surface. Approaching the limit stress causes excessive deformation of the pad and material entering the necking condition, leading to incomplete cleaning or premature material degradation. Slower pad moving speed reduces friction during pad-nozzle interaction, enhancing nozzle surface cleanliness. Nevertheless, the non-normal distribution of pad moving speed data may affect data analysis, necessitating caution in interpreting the improvement of data in this study.

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