| 摘要: | RDL(Re-distribution layer)製程應用在高頻元件可包含銅線路及凸塊，此時應用甲基磺酸電鍍(methanesulfonic acid ,MSA)，由於銅離子濃度可以提高，電流密度也高，此方法與傳統的硫酸銅電鍍線路比較可節省生產成本，但此應用於重佈線層光阻在密集線路區域，經銅電鍍製程後，易發生光阻破裂的問題。
此光阻破裂問題必需要完全避免，因此，為了避免線路短路及降低二次電鍍的風險，以增加製程穩定性，本研究利用實驗的方式，改變不同的製程條件，逐步釐清造成光阻破裂的非影響因素，如軟烤溫度、軟烤時間、曝光量、曝光間距、光源種類、線路圖形、電鍍添加劑、電鍍沉積速度等，以及影響因素，包含光阻厚度、電鍍銅厚度、光阻尺寸等，如此，找到可影響此缺陷數量的關鍵因素，根據實驗的結果，發現可依此訂定製程設計規則表，例如銅厚度在12μm時，光阻寬度大於等於10μm以上，即線距大於等於10μm以上，則不會發生此光阻破裂的問題，使重佈線層的光阻保持完整，進而降低銅滲鍍及短路的風險。結果顯示，此光阻裂紋缺陷會藉由製程條件的搭配，此缺陷明顯獲得改善。
;The re-distribution layer (RDL) application in high frequency component can include copper lines and bumps, the application of methanesulfonic acid (MSA) plating at this time, due to the copper solution’s ion concentration can be increased and high current density. This method compared with the traditional copper sulfate plating could save more costs, but the dense line of photo-resist under this application is easily crack after plating procedure. Therefore, in order to avoid short circuit and reduce the risk of secondary plating, and then increase the stability of the process, this study used experimental methods to test the different process conditions, and gradually to clarify the cause of the non-influencing factors of photoresist crack such as soft roasting temperature, soft roasting time, exposure, exposure spacing, light source type, circuit pattern, plating additive, plating deposition rate, etc., and influencing factors including photoresist thickness, copper plating thickness, photoresist size .After those study, we could got the key factors that can affect the number of defects. According to the experimental results, the design guidelines is summarized. Such as copper thickness 12μm, the photoresist width greater than or equal to 10 or more. That spacing is greater than and Equal to 10 or more. The cracking of the photo-resist does not occur after plating. The photoresist of the re-distribution layer keeps complete to next stage, and the risk of copper plating and short were reduced. The results show that this photoresist crack defects will be matched by the process conditions, this defect has been significantly improved. |
