Surface chemical modification of InN for sensor applications

The effect of chemical exposures on the InN surface is reported. InN surface shows a fast capture, slow release, responsivity, and selectivity to certain solvent exposures, such as methanol and water. Enhancement in sheet carrier density as large as 7×1012cm−2 with a simultaneous increase in Hall mobility of thin InN films was determined by Hall measurements. A corresponding reduction in sheet resistance of more than 30% was measured on a 20nm InN film. The added electrons are likely to be surface carriers whose density decays after the solvent fully evaporates. This study shows the promise of using the sensitive InN surface for sensor applications.