Impedance characterization of nanogap interdigitated electrode arrays fabricated by tilted angle evaporation for electrochemical biosensor applications

Abstract

Nanogap interdigitated electrode (IDE) arrays were fabricated by tilted angle evaporation on dry etch SiO2 substrates, suggesting a simple, inexpensive, and controllable fabrication technique. The impedance characteristics in a KCl solution clearly showed the differences between nanogap and microscaled IDEs in terms of the peak positions of the phase shift and the ratio of the resistance amplitudes. Moreover, the effect of imperfections on the edge of electrodes was quantitatively discussed through the analysis of electric-field based on finite element method. Our results provide a better understanding of impedance behavior of nanogap IDE arrays for high-performance biochemical applications. (C) 2014 American Vacuum Society.