Flexible and extendible neural stimulation/recording device based on cooperative multi-chip CMOS LSI architecture

An LSI-based cooperative multi-chip neural stimulation/recording device is proposed and fabricated. The proposed multi-chip device consists of small (600 μm × 600 μm in the present design) intelligent neural stimulation/recording chips (unit chip). The unit chip has a neural stimulation/recording electrode array and individual control circuit. It can work with other unit chips cooperatively. One can configure any number of the unit chips as the multi-chip neural stimulation/recording device. Compared to conventional single-chip architecture, the proposed multi-chip architecture has advantages in thinness, mechanical strength and flexibility, and extendibility. That makes the multi-chip neural stimulation/ recording device more suitable for in vivo applications than conventional single-chip devices. Packaging technology for cooperative multi-chip device is also discussed. We developed a thin, flexible packaging technique for the multi-chip neural stimulation/recording device and LSI-compatible Pt/Au stacked biocompatible bump electrode.