3D-interconnect approach for high end electronics

This paper presents 3D-interconnect technology to produce a variety of structures and packages suitable for high end electronics. 3D-interconnect can join different size multiple rigid structures for rigid-rigid constructions. For example, a high density circuit card and a low end printed wiring board were attached using 3D-interconnect to achieve functionality similar to a complex board. Various sub-composites, signal-power cores, were laminated with paste filed joining cores (0S/1P) or joining layers (0S/0P) to improve wiring density of a package. A 3D “Package-Interposer-Package” (PIP) integration method was used to attach multiple assembled substrates. An example of a structure consisting of seven stacked substrates attached using PIP approach is given. The PIP approach can provide for replacement, repair, or upgrade of individual substrates in the stack, beneficial for processing of complex, expensive product. In addition 3D-micro bump technology was developed as am alternative to solder based, pasteless 3D interconnects. A variety of materials and processes, including paste, Cu micro pillars, and solder-based micro-bumps were developed for 3D-interconnects. Overall, the present work describes an integrated approach to develop 3D interconnect constructions on various complex package, stacked package, or stacked die packaged configurations.