A Study on Wire Sweep in Encapsulation of Semiconductor Chips Using Simulated Experiments

Abstract

An effort has been made in this study to develop a model which can predict wire sweep during semiconductor chip encapsulation with transfer molding. The calculation of wire sweep during encapsulation depends on many factors. In this study, a step-by-step approach has been used considering one factor at a time. As the first step, the wire deformation has been measured and calculated under a known dead-weight loading. The next step has been to measure and calculate the deformation of a single straight wire attached to the mid-plane of a rectangular cavity due to the flow of a clear and homogeneous fluid. Finally, the wire deformation due to the flow has been measured and calculated when a wire of general shape is attached to a leadframe. The effect of bubble on the wire-sweep has been analyzed qualitatively. Through this series of experiments, a first step in the development of model for the prediction of wire sweep during chip encapsulation has been made.