Mechanical analysis and reliability enhancement of a Proximity Communication flip chip package

Proximity Communication is a technology that enables high-bandwidth chip-to-chip signaling using dense arrays of metal pads that are capacitively coupled to the corresponding pads on the neighboring chip. To successfully deploy Proximity Communication requires limiting chip x-y misalignment and separation to be less than 8 µm and maintaining these tolerances over many temperature cycles. This paper examines these requirements in light of test results and detailed mechanical modeling to both understand the performance of existing package designs and to identify design modifications that lead to improved performance.