Strain‐Engineered Gradient‐Modulus Platforms for Mechanically Robust and Conformable Hybrid Electronics

ABSTRACT Stretchable hybrid electronics offer a compelling pathway for integrating rigid microelectronic components within soft, deformable platforms, crucial for the development of next‐generation wearable and epidermal devices. However, the pronounced mechanical mismatch at the interface between stiff components and elastomeric substrates often leads to interfacial failure, including delamination and cracking, under dynamic strain conditions. In this study, we present a mechanically optimized and electrically resilient stretchable hybrid electronic system by co‐designing substrate mechanics and conductive architectures. A photolithographically defined gradient crosslinking technique is utilized to fabricate a modulus‐graded polydimethylsiloxane (PDMS) substrate, exhibiting a spatially tunable elastic modulus ranging from 0.12 to 1.4 MPa. This gradient‐modulus configuration enables effective redistribution of localized strain, thereby alleviating stress concentration and enhancing mechanical durability at heterogeneous interfaces. Concurrently, a silver‐PDMS composite conductor is developed, achieving high conductivity (1 Ω/sq under 50% strain), excellent stretchability, and environmental robustness. Direct‐ink‐writing using an inkjet platform facilitates precise patterning of conductive traces, allowing seamless integration of multifunctional sensor arrays capable of real‐time monitoring of wrist kinematics and complex finger movements. This work underscores the synergistic integration of gradient mechanical engineering and scalable microfabrication strategies, paving the way for robust, high‐fidelity wearable electronics and electronic skin systems.