Intel Corporation
Method to achieve variable dielectric thickness in packages for better electrical performance

Abstract:

Embodiments include packages substrates and a method of forming the package substrate. A package substrate includes a first dielectric comprising a first conductive layer, and a second dielectric comprising a second conductive layer and a third conductive layer. The second and third conductive layers are embedded in the second dielectric, where a top surface of the third conductive layer is above a top surface of the second conductive layer. The package substrate has a fourth conductive layer on the second dielectric. The first dielectric has a first dielectric thickness between the first and third conductive layers. The first dielectric also has a second dielectric thickness between the first and second conductive layers. The package substrate includes the second dielectric thickness that is greater than the first dielectric thickness. The second dielectric may have a z-height of a first bottom surface greater than a z-height of a second bottom surface.