A Novel pH Sensor Using Extended-Gate Field-Effect Transistors with Ga2O3 Nanowires Fabricated on SiO2/Si Template

摘要

We report the growth of beta-Ga2O3 nanowire with a length of the order of micrometers using a vapor phase transport method. We used an extended-gate field-effect transistor (EGFET) to demonstrate, for the first time, the response of the synthesized beta-Ga2O3 nanowires as a function of pH. The samples were analyzed by FESEM, XRD, HRTEM and measured by a semiconductor parameter analyzer. The sensitivity of the sensors, which were quantified from the slopes of the I-Ds-pH and V-REF-pH relations, were found to be 15.8 mu A/pH and 24.8 mV/pH, respectively. These results suggest possibilities for the design of high-performance pH sensors based on beta-Ga2O3 nanowires with large surface area with more binding sites and larger effective sensing capabilities.