A CMOS-Compatible and Actuatable 3D-Microcage Array with Shape-Memory for On-Chip Dynamic Cell Interfacing

Advancing our understanding of cellular behaviors necessitates effective interfacing within three-dimensional (3D) microenvironments. Most complementary metal oxide-semiconductor (CMOS)-based microelectrode arrays (MEAs) rely on planar electrode cell-interface, limiting them to 2D cell monitoring. While recent developments have introduced 3D electrodes for improved spatial resolution and cell interfacing, these configurations remain static and lack dynamic manipulation capabilities. This work introduces a novel surface electrochemical actuator (SEA)-based microcage array featuring shape-memory curvature and individually addressable arms for advanced cellular interfacing. Fabricated through standard silicon processing techniques, the SEA-based microcage array demonstrates CMOS post-processing compatibility, facilitating seamless integration with CMOS electronics for precise microscale control and minimized signal interference. Mechanical durability and thermal stability assessments confirm the device robustness. Cell culturing and electrochemical experiments confirms device biocompatibility and cell interfacing capability as sensing electrode.