Gas Detection with Vertical InAs Nanowire Arrays

Nanowire-based devices show great promise for next generation (bio)chemical sensors as evidenced by the large volume of high-quality publications Here, a nanoscale gas sensing device is presented, based on gold-free grown vertical InAs nanowire arrays The nanowires are contacted Ohmically in their as-grown locations using an air bridge construction, leaving the nanowire surface free for gas adsorption Noise measurements were performed to determine the measurement resolution for gas detection These devices are sensitive to NO2 concentrations well below 100 ppb at room temperature NO2 exposure leads to both a reduction in carrier density and electron mobility