The copper stud bumping shaping simulation based on thermal-solid couple analysis

With electronic production tending to be large scale integration, digital, lightweight, small-lot and diversification, the traditional bumping fabrication technologies aren´t compatible with the electronic production such as the personalized, medical implants, military and new product development and so on for cost problem. And then the single chip bumping technology is introduced, among which the stud bumping technology becomes one of the most important technologies due to compatible with wire bonding machine, no UBM, flexible and fine pitch fabrication advantages. However because of the narrow process window of copper stud bumping, easily Si crater and Al sputtering in bonding process, so reasonable setting process parameters is critical. By using of the explicit finite element method which is more suitable for contact and collision simulation, the three dimensional copper stud bumping model is developed, and then the relevant thermal material properties are added into the K file to realize the thermal-solid analysis and validation of the model is verified.