Package demonstration of an interposer with integrated TSVs and flexible compliant interconnects

We report on the development of a test package that utilizes a passive silicon interposer with high density and high aspect ratio TSV's, each integrated with compliant flexible interconnect on one side of the interposer. As opposed to conventional approaches, where TSV interposers are populated with C4 and/or fine pitch micro bumps with multiple interfaces to reflow and permanently attach, our TSV interposers are integrated with micro-spring interconnects on a single side or, potentially, on both sides to provide a truly reworkable or reusable (“rematable”) MCM platform. This makes it possible to test die in package while retaining the ability to replace any that are found flawed. This is a key requirement for increasing assembly yield of advanced MCM packages.