Stress reduction for flip chip package

摘要

The bond between a flip chip integrated circuit and a substrate is subject to mechanical stress from thermal cycles. The invention involves creating an anchoring point. The anchoring point can be in either the IC or the substrate and can be a through-hole or a surface indentation such as a groove or a cutout. The anchoring point is filled with the underfill material during the underfill process. The anchoring point thus provides additional mechanical strength to the bond between the IC and the substrate.