A 16-site neural recording probe array and its circuit model simulation

This paper introduces a simple MEMS (micro electromechanical system) process to fabricate a 16-site neural recording probe array and gives a detailed characterization of the neuron-electrode interface, based on the equivalent circuit approach. The impedance magnitude of the probes shows approximately a constant slope of f^-0.75 from 100Hz up to 1MHz. The action potential can be simulated by the general-purpose circuit simulation program, such as HSPICE. The responses of the microelectrodes act as a function of several parameters, such as the sealing resistance and input resistance of the preamplifier. The responses are not sensitive to the changes of the microelectrode parameters. However, appreciable influence of the parasitic capacitance was obtained when the sealing resistance was large (e.g. 100MΩ).