Post-bond Scan-Based Testing of Interposer Interconnects

Abstract

Interposer testing must be done at the pre-bond stage and at the post-bond stage. While pre-bond testing is obviously important and is receiving attention [1], including in Chap. 2 of this book, the focus of this chapter is on post-bond testing, which allows us to target defects in the interposer interconnects and the micro-bumps in an integrated manner. Post-bond testing allows us to detect defects in the interposer (e.g., shorts and opens), as well as faults due to missing or deformed micro-bumps faults that cause misalignment between dies, micro-bumps, and the interposer. However, post-bond testing is difficult due to limited access to the TSVs and the RDL inside the interposer.