Thermal evaporation based V2O5 thin film for extended gate field effect transistor pH sensor

Abstract

In this work, vanadium pentoxide (V2O5) thin film was synthesized on the corning glass substrate by using thermal evaporation method. For this purpose, 99.9% pure V2O5 powder was used that was evaporated from a tungsten boat. Subsequently, the prepared film was used as pH sensor in the extended gate field-effect transistor (EGFET) system. Structural properties, morphological features, sensing performance and linearity measurements of synthesized film were studied. The structural properties indicated that the V2O5 thin film has the preferred orientation along (001) plane. The pH-EGFET sensor based on V2O5 thin film was fabricated. The sensitivity and linearity of the device were determined in the pH range of 2-12 of the buffer solution. The sensitivity and linearity values were found to be 41.7 mV pH-1 and 83% respectively in the linear region. The results of present study show that the V2O5 can act as promising material for the EGFET PH sensor.