Design Analysis in a Cavity with Leadframe during Semiconductor Chip Encapsulation

반도체 칩 캡슐화(encapsulation)를 위한 트랜스퍼 금형 캐비티(cavity)에서의 설계 해석 및 실험에 관한 연구

An effort has been made to more accurately analyze the flow in the chip cavity, particularly to model the flow through the openings in the leadframe and correctly treat the thermal boundary condition at the leadframe. The theoretical analysis of the flow has been done by using the Hele- Shaw approximation in each cavity separated by a leadframe. The cross-flow through the openings in the leadframe has been incorporated into the Hele-Shaw formulation as a mass source term. The temperature of the leadframe has been calculated based on energy balance in the leadframe. The flow behavior in the leadframe has been verified experimentally. In the experiment, a transparent mold and clear fluid have been used for flow visualization. Comparisons were made between the calculation and experimental results which showed a good agreement.