A novel implantable multichannel silicon-based microelectrode

摘要

Silicon-based microelectrodes have been confirmed to be helpful in neural prostheses. The fabricated 7-channel silicon-based microelectrode was feasible to be implanted into the brain cortex. The manufacturing process by microelectromechanical system (MEMS) technology was detailed with four photolithographic masks. The microscopic photographs and SEM images indicated that the probe shank was 3 mm long, 100μm wide and 20μm thick with the recording sites spaced 120μm apart for good signal isolation. To facilitate the insertion and minimize the trauma,the microelectrode is narrowed down gradually near the tip with the tip taper angle of 6 degrees. Curve of the single recording site impedance versus frequency was shown by test in vitro and the impedance declined from 150.5 kΩ to 6.0 kΩwith frequency changing from 10 k to 10 MHz.