This disclosure provides an integrated circuit device that includes a RDL that is interlocked with a bump (or “pillar”). The interlocked interface provides the contact RDL-bump interface with increased structural stability that can better withstand the thermal stresses associated with high performance devices IC devices. The interlock structure mitigates crack/delamination that occurs at the RDL-bump interface in large IC chips that are generally subjected to higher stresses during operation.