Patent ID: 6475327
Filing Date: 2002-11-05
Classification: H01L

Abstract:
A method of attaching a stiff heat spreader element to a circuit substrate for making a cavity down plastic chip carrier, comprising:providing a plastic circuit substrate having a first surface and a second surface opposite said first surface, and an opening penetrating through said circuit substrate adapted to receive a chip; providing a first thermally conductive sheet which serves as a stiff heat spreader element having a first surface and a second surface opposite said first surface; providing a second thermally conductive sheet having a first surface and a second surface opposite said first surface, and having an opening penetrating through said second thermally conductive sheet for receiving said chip; providing a first bonding sheet, being at least one layer of prepreg made of fiber-reinforced resin, bonding said first surface of said first thermally conductive sheet to said second surface of said second thermally conductive sheet; providing a second bonding sheet, being made without a prepreg, bonding said first surface of said second thermally conductive sheet and said second surface of said circuit substrate.