Separate structure extended gate H +-ion sensitive field effect transistor on a glass substrate

Abstract

In our research, glass was used as a substrate for an H + ion sensitive field effect transistor (ISFET). The sensitive characteristics of five structures for separate extended gate ion sensitive field effect transistors (EGFET) were studied. The components included tin oxide (SnO 2)/aluminum/micro slide glass, tin oxide/aluminum/corning glass, indium tin oxide (ITO) glass, tin oxide/indium tin oxide glass and tin oxide/micro slide glass. Indium tin oxide (ITO) thin film was first time used as an H + ion sensitive film, which has a linear pH Nerstern response sensitivity, about 58 mV/pH, between pH 2 and 12. In addition, the sensing area effect of the tin oxide/glass, tin oxide/ITO glass and ITO glass structure is discussed. The results show that the tin oxide/ITO glass structure EGFET has the best drift, hysteresis and sensing area characteristics.