Solder-free room-temperature multichannel integration for soft hybrid electronics

Abstract

Soft hybrid electronics that interconnect soft modules and rigid circuit components hold significant promise for applications in wearables, robotics, and biomedicine. However, existing interconnection methods face critical challenges, including thermal damage from high-temperature welding, complicated chemical processing, and inadequate mechanical bonding, which often lead to interfacial deformation and electrical failure. Here, we introduce a room-temperature direct interconnection (RTDI) technique that leverages hydrogen bonding and molecular chain entanglement to form robust, solder-free, multichannel interfaces between soft and rigid modules. The resulting interface achieves an exceptional mechanical bonding strength of 210.4 N m⁻¹ (24.7-fold higher than conventional silver paste), and an electrical stretchability of 173.6% with relatively stable resistance at 110% strain. As a proof of concept, we demonstrate the RTDI technique in two applications: multi-channel interconnections for stretchable displays and vertical chip integration for logic-controlled display systems. Owing to its simplicity and scalability, this method provides a powerful pathway for advancing multifunctional hybrid electronic integration.

Keywords

multichannel integration / room-temperature·interconnection / soft hybrid electronics / soft–rigid interface / solder-free

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