Method to improve internal package delamination and wire bond reliability using non-homogeneous molding compound pellets

摘要

Method for implementing a multi-phase plastic package for electronic components, and packaged electronic components produced according to the method. The present invention contemplates the use of molding compounds having two or more discrete phases in a transfer molding process wherein a temperature differential is induced between the electronic component to be packaged and the mold of the molding apparatus prior to molding. Each of the molding compound phases, when used in a current transfer molding apparatus, generates a separate layer in the resultant package, and each of the resultant layers possesses certain unique properties. In its simplest implementation, the present invention provides a two-phase molding compound pellet which provides an outer layer containing mold release compounds to facilitate release of the completed packaged device from the mold, and an inner layer without mold release agents. Other implementations include multiple layers. One such implementation provides for an inner layer without flame retardants and a layer exterior to the inner layer containing flame retardants. In this manner, chemical interaction between the flame retardants and the encapsulated device is precluded. Other adjuncts may, with equal facility, be implemented in such additional layers as a given application may require.