應用實驗設計提升LED鋁線銲線製程品質-以X公司為例

Abstract

發光二極體(Light-Emitting Diode, LED) 應用面很廣，例如:指示燈、照明燈、背光源、顯示屏、警示燈等，LED未來更可能會全面取代傳統燈泡，因此LED產品的發展將會越來越蓬勃。在LED的封裝製程中又以銲線製程最為重要，若銲線製程品質不穩定將會造成LED產品嚴重失效，而LED銲線線材一般分為金線、鋁線兩類，金線成本較鋁線高，企業在成本的考量下通常會選擇鋁線銲線。因此本研究以國內某家著名的LED專業封裝廠為案例公司(以下簡稱為X公司)，應用實驗設計(Design of Experiments, DOE)中之Box-Behnken設計求出使鋁線銲線拉力值最大之機台參數最佳設定值來提升LED封裝鋁線銲線製程品質。本研究所找出之最佳配方經驗證後顯示銲線拉力製程能力指標(Process Capability Index, Cpk)可大幅提升。

Lighting-Emitting Diode (LED) can be applied in many areas, such as indicators, lightings, backlights, displays and warning lights and so on. In the future, it is expected that LED will be completely replace the traditional tungsten lamp and has a bright perspective in the market. In LED package process, wire bonding is the most important sub-process. If the quality of wire bonding is unstable, it would affect the lighting function of LED seriously. Generally, the material of wire for LED can be divided as gold wire and aluminum wire. The cost of gold wire is much higher than aluminum wire. For the consideration of cost, aluminum wire is generally selected for wire bonding process. This study utilizes a SMD LED package company (X Company) in Taiwan as a case study. In order to maximize the wire pull, Box-Behnken Design of Design of Experiments (DOE) is employed to find out the optimal parameter setting for wire bonding machine and expect to enhance aluminum wire bonding quality during LED package process. The result of this study has proved that the wire pull process capability index (Cpk) has significantly increased by using the optimal parameter setting.