Embodiments of the disclosure relate to an apparatus and method for mitigation of warping of assembly components when subject to a thermal event. An interface unit with a complementary coefficient of thermal expansion is embodied in the assembly. The interface unit is configured to be received by a connector joined to the assembly substrate. The interface unit has a coefficient of thermal expansion (CTE) that complements the CTE of the assembly components in order to maintain the connector in alignment with the substrate and enable the connector to expand or contract with the substrate when subject to the thermal event.