Ultrasensitive Poly-Si nanogap based on capacitive sensor for electrochemical detection

Nanogap has become a new emerging subject to researcher around the globe for its complementary study with biomolecule and ionic level detection. Higher sensitivity and selectivity in sensing device attained by nanogap has resolved many limitations faced by previous bulk device. For this project, we present a novelty device provide ultrasensitive label-free detection using real time measurement. The fabrication of device involves only conventional lithographic process and simple dry oxidation process. By using 42 nm nanogap devices, the sensitivity of nanogap were tested by dropping 10μL of different level pH and NaCl concentrations onto the target. Experiments were performed by sweeping frequencies from 1 Hz to 1 MHz at room temperature with 30 mV input signal(0 V, DC, Offset). The effects of excitation frequency on capacitance sampling were analyzed.