Analysis of heat generation of epoxy compounds for encapsulation of semiconductor devices. Part I: formulation of a mathematical model

摘要

A mathematical model for predicting heat generation caused by the chemical reaction of epoxy compounds used for encapsulation of semiconductor devices has been developed. First, a model to describe isothermal heat flow changes was derived as a function of time and temperature. On the basis of this model, procedures to describe heat generation under actual non - isothermal conditions were developed. Two kinds of commercial molding compounds were used in this study. Parameters in the model were determined by isothermal DSC (Differential Scanning Calorimetry) runs. The calculated heat flow profiles fit well with experimental data for both isothermal conditions and for a heating rate of 5 K/min. For a heating rate of 20 K/min, the peaks of the calculated values of both materials were higher than those for the experimental data. The discrepancy was caused by the model neglecting the phenomenon of total heat saturation at a defined temperature T{sub}L corresponding to the glass-transition temperature T{sub}g. After accounting for the T{sub}L calculated profiles fit well with the experimental data under all conditions.