Substrate cores for warpage control

Abstract

According to the various aspects, a package substrate (102, 402, 502, 902) with a heterogeneous substrate core (101, 201, 301, 401, 501, 601, 701, 801, 901) including a first core layer (101a, 201a, 301a, 401a, 601a, 701a, 801a) that is coextensive with the package substrate and extends through a first section (120, 220, 320, 420, 520, 820, 820a, 920) and a second section (122, 222, 322, 422, 522, 822, 922) of the substrate core, in which the first section is adjacent to and thicker than the second section. The first section having at least a second layer (101b, 201b, 301b, 401b, 601b, 701b, 801b) and / or a third layer (101c, 201c, 301c, 401c, 601c, 701c, 801c) to provide the difference in thickness with the second section.