Fig. 1: One-step μETF of LCP MEA to create microscopic protruding and recessed 3D structures for enhanced neural interfaces.

a Benefits of localized neural interface (e.g., lower threshold and inter-channel interference) achieved by 3D structures. b Schematic illustration of μETF process to transfer 3D structures of the 3D mold onto planar LCP MEA. c Cross-sectional illustration of subsequent micro- and macrothermoforming processes for achieving both high proximity to target cells and conformability to surrounding tissues. d Schematics (top row) and photographs (bottom row) of LCP MEA (i) before μETF, after ii) protruding or iii) recessed 80-μm-height μETF, and (iv) after macro-ETF to fit eye curvature. Scale bars: 1 mm. e SEM images and f) cross-sectional images of (i) planar, (ii) 80-μm-protruding, and (iii) 80-μm-recessed electrode sites of μETF LCP MEA. Scale bars: 100 μm. g Optical profiles of protruding (top) and recessed (bottom) electrode sites.