Multiscale Finite Element Analysis of Warping Suppression in Microelectronics with Graded SiC/Al Composites.

High-power microelectronic packaging faces critical thermomechanical failures under rapid thermal cycling, primarily due to interfacial stress concentration and warping in conventional homogeneous heat sinks. To address this challenge, this study proposes a novel functionally graded SiC/Al composite with a tailored thermal expansion coefficient (CTE) gradient, designed to achieve adaptive thermal expansion matching between the chip and heat sink. Through multiscale finite element analysis, the stress-strain behavior and warping characteristics of homogeneous (Cu and Al) and gradient materials were systematically investigated. The results show that the gradient SiC/Al design significantly reduces the peak thermal stress and maximum warping deformation. The progressive CTE transition effectively mitigates abrupt interfacial strain jumps and extends device lifespan under extreme thermal loads. This advancement positions gradient SiC/Al composites as a key enabler for next-generation high-density packaging and power electronics requiring cyclic thermal stability. The study provides both theoretical insights into thermomechanical coupling and practical guidelines for designing robust electronic packaging solutions.