A heterogenous integrated neural recording system with elastocapillary self-assembled Au-PDMS-PEG neural probe and customized ASIC

This study presents the design and implementation of a heterogenous integrated neural recording system consisting of a flexible Au-PDMS-PEG probe and customized complementary metal oxide semiconductor (CMOS) application-specific integrated circuit (ASIC) in a standard 0.18 μm process. The flexible Au-PDMS-PEG probe was prepared by an elastocapillary self-assembled process, achieving an electrode impedance of 250 kΩ (@1 kHz). The customized CMOS ASIC contains 36 modular digital pixels (MDP). It achieves 5.69 μV_rms input referred noise, 10.29 effective number of bits, 49.5 μW power consumption, and 0.092 mm² area for a single MDP unit. Spontaneous spikes were also recorded in the mouse cortex, with a peak-to-peak amplitude of 389.2 μV_PP and a signal-to-noise ratio of 19.36. Benchtop and in-vivo experiments were conducted to validate the functionality and performance of the proposed neural recording system.