Effect of different dielectric materials on enzyme field effect transistor

This paper presents the effects of different dielectrics used as gate insulating material in the enzyme field effect transistor (ENFET) device. Different insulating materials have different properties which put an impact on the device sensitivity. The acid and base equilibrium of the dielectrics bring changes to the ENFET sensitivity. The pHpzc (pH at point of zero charge) is different for different dielectric material which also results in variations in the surface potential. The device model was tested for substrate sample with pH varying from 2 to 12. The potential variation that occurs at the surface of the device due to change in gate insulator was recorded and compared. It was found that with different gate insulating materials, the sensitivity of the device also varies. Ta2O5 was recorded as the most sensitive device under certain assumptions as compared to other insulating materials like SiO2, Al2O3, ZrO2, HfO2 and TiO2. The sensitivity variation with temperature is also shown for different materials.