Neural recording with low-invasive Si microprobe array

Reported here is Si microprobe electrode array, developed for using in the recording of neurons in the tissue. The probe array can be fabricated on IC chip, using standard IC process followed by a selective Si probe growth. In this work, the Si probes with 2-4 μm in diameter were fabricated. The probe array could provide low-invasiveness and low damage to neurons in the neural electrode penetration. The resistance of the probe was 1 kΩ, and the impedance, measured in saline, was less than 500 kΩ, at 1 kHz. Neural recording was carried out using the retina of a carp (Cyrpinus carpio), and light-evoked neural responses of the retina were recorded with the Si microprobe electrodes.