Bacteria Sensors Based on Interdigitated Silicon Nanowires Electrodes

Abstract

The detection of pathogenic bacteria in food, water and air is an important issue because of its critical impact on public health, especially with the emergence of multi-resistant bacteria. Standard microbiological methods of bacterial culture impose deadlines that can slow down the establishment of means of protocols against contaminations. In this context, a strategy is to develop ultrasensitive sensors based on silicon nanowires networks for rapid detection of bacteria. Indeed, the nanowires have a large contact surface allowing preferential interactions with the bacteria. Resistors based on silicon nanowires used as bacteria sensors are fabricated using conventional silicon technologies. The nanowires are obtained by the VLS (Liquid Solid Vapor) method using gold as catalyst and the interdigited comb electrodes are made of high doped polycrystalline silicon. The bacteria are preferentially attached to the nanowire network (fig. 1a and b). The electrical characterization of the the devices shows that the current through the resistors increases significantly due to the presence of bacteria (fig. 1c). The results show the potential use of the resistors, with the nanowires as sensitive units, for the detection of bacteria. Figure 1