CMOS Microelectrode Array for Signal Recording and Stimulating of Neurons Assemble

A microelectrode array (MEA) chip for in-vitro signal recording and stimulating of neurons assemble is presented. The chip comprises 4times4 active sensor cells and ESD protection circuits. Each sensor cell is 60 mumtimes60 mum in dimension, including a 15 mumtimes25 mum stimulating electrode, a 15 mumtimes25 mum recording electrode and two NMOS switches which can linearly transfer signals with peak-to-peak values from 50 muV to 500 mV. The final chip is realized in a standard 0.5 mum DPDM (double-poly double-metal) CMOS technology. It covers an area of 1.0 mmtimes1.0 mm. The results of on-wafer electrical test indicate the independent electrical characteristic of the stimulating electrode and the recording electrode and verify the functionality of the NMOS switches. The tests carried out in the NaCl solution for the packaged chip have verified the electrical functionality of the MEA chip.