Lithographically defined vertical interconnect access (via) in dielectric pockets in a package substrate

Abstract

Techniques for fabricating a package substrate comprising a via, a conductive line, and a pad are described. The package substrate can be included in a semiconductor package. For one technique, a package substrate includes: a pad in a dielectric layer; a via; and a conductive line. The via and the conductive line can be part of a structure. Alternatively, the conductive line can be adjacent to the via. The dielectric layer can include a pocket above the pad. One or more portions of the via may be formed in the pocket above the pad. Zero or more portions of the via can be formed on the dielectric layer outside the pocket. In some scenarios, no pad is above the via. The package substrate provides several advantages. One exemplary advantage is that the package substrate can assist with increasing an input/output density per millimeter per layer (IO/mm/layer) of the package substrate.