Development of Indium Arsenide Nanowire Field-Effect Transistors as Chemical Sensors
Author | : Alex Chi-Wei Tseng |
Publisher | : |
Total Pages | : 0 |
Release | : 2018 |
ISBN-10 | : OCLC:1335046358 |
ISBN-13 | : |
Rating | : 4/5 (58 Downloads) |
Book excerpt: Chemical sensors based on field-effect transistors were fabricated from hundreds of aligned indium arsenide nanowires which show promise for high performance based on their high electron mobility and charge sensitivity. Sensing responses to analytes in vapour and solution phases were collected from these multi-wire devices via real-time current measurements and parameters extracted from electrical transport characterization. In the vapour phase, a linear response to acetic acid was observed in surface charge densities determined from a model for the sub-threshold behaviour. These responses distinguished between strongly chemisorptive bonding of acetic acid versus weaker bonding of methanol and 2-butanone. In the solution phase, near-Nernstian sensitivity to sodium ions of a crown ether functionalized, fluorosilicone membrane was determined from the threshold voltage and hysteresis in transport characteristics. A Nernst-Planck-Poisson model was investigated to interpret the electro-diffusive processes but did not accurately capture the electric field dependence. Suggestions to address the shortcomings are given.