摘要 隨著半導體工業的發展，使用大尺寸晶圓已經是現今的趨勢，如何能夠了解並運用不穩定手指狀流的產生，並順利將光阻液塗滿晶圓且塗佈均勻，是旋轉塗佈過程中的重點。 本實驗利用實驗結果與數值模擬分析，探討科氏力應用於大尺寸晶圓的塗佈上，對於不穩定手指狀流所產生的影響，發現科氏力雖然對於薄膜的厚度分布並無太大的影響；但是由於製程中科氏力的介入，使得不穩定手指狀流偏向產生匯流的狀況，使得流體的塗佈面積增大，反而利於旋轉塗佈製程。並且探討預塗薄膜應用於旋轉塗佈的影響，發現預塗薄膜對相對黏滯係數較高的流體影響較大，由於表面張力減小的關係，使得相對黏滯係數較高的流體之臨界半徑較晚產生，而且注液時薄膜波前行進速度較未預塗時加快許多，並且沒有停滯的現象，因此晶圓可以很容易的就被塗佈。 Spin coating is utilized widely in the microelectronics industry to form thin uniform films of photoresist, spin-on-glass, polyimide, and low dielectric constant materials on silicon wafers. This coating technique is quick and efficient. But, liquids such as photoresist are very expensive. During coating process, the maximum radius that can be coated is limited by a contact line instability, leading to the formation of rivulets or “fingers” at the leading edge. The onset of fingering instability makes the coating process inefficient and significantly affects whether a wafer can be fully coated. One of the most critical roles for spin coating systems is to properly cast a thin film of photoresist on the surface of a silicon wafer. In this project, a new spin coating process is proposed to overcome the problem of partially coated especially for large size wafer such as the wafer with diameter 300 mm or even 450 mm. The perwetting spin coating decreases the rotational speed of the wafer, thus preventing the wind shear effect. And experimental results show that coriolis force broadens the width of fingers. We can utilize the results to find a new spin coating technique so that a uniform film can be obtained.
