The Electrical Characterization of Nitride/Oxide Ion Sensitive Field Effect Transistor (NO-ISFET)

This article describes the electrical characterization of the Nitride/Oxide Ion Sensitive Field Effect Transistor (NO-ISFET). The ISFET was processed with a standard 0.8 μm CMOS process. The ISFET structural in this study contains 10 nm thick oxide, capped with 30 nm thick silicon nitride acting as a sensing film. The designed dimension, channel width per channel length (W/L) is 2000μm/100μm. The I
_DS
-V
_GS
and I
_DS
-V
_DS
characteristics of the device based on this proposed structure are measured.From the experiment, our ISFET exhibited the pH sensitivity approximately 56.67 mV/pH. The measured current sensitivity is about 9 μA/pH at V
_DS
of 0.3 V and the gate voltage (V
_GS
) of 1.2 V.