Forged flip chip lids are identified as having a rectangular profile where the top of the package extends to the full package body dimensions. From a thermal perspective, forged lids are generally superior to stamped lids, particularly in reduced conduction situations due to the fact the lid has more surface area for a heatsink to touch for a given package size. The lid itself is generally thicker leading to more heat spreading within the lid prior to heat sink extraction. The following figure shows the cross section and top view of a forged lid, also known as a type I lid.
