Nanoneedle-Electrode Array Packaged with Amplifiers for Recording Biological-Signals with A High Voltage Gain

We have proposed nanoscale-tipped microneedle-electrodes by vapor-liquid-solid growth of silicon microwire and the subsequent sharpening process. However, due to the small area of the recording site (<; 1 μm in diameter), the needle exhibits high electrical impedance characteristics, causing amplitude attenuation of recorded signals at > 100 Hz. To overcome the device issue, here we designed and fabricated a buffer amplifier using a 1×1 mm
²
silicon-block. Assembling the buffer amplifier improves the gain of the nanoneedle device, as confirmed in the test signal recording. These results suggest that the nanoneedle device with buffer amplifier enables recording of high signal amplitude of neuron and cell.