Complementary Metal-Oxide-Semiconductor Ion-Sensitive Field-Effect Transistor Sensor Array with Silicon Nitride Film Formed by Catalytic Chemical Vapor Deposition as an Ion-Sensitive Membrane

摘要

Integration of 16×16 and 32 × 32 extended-gate ion-sensitive field-effect transistor (ISFET) arrays with a low-power consumption read-out circuitry has been reported. Si_3N_4 film used as a pH sensitive layer is deposited on the 4 × 4μm~2 extended-gate electrodes of ISFETs in the integrated circuit by catalytic chemical vapor deposition (Cat-CVD). The average pH sensitivity is 41 mV/pH, and the distribution obeys a Gaussian distribution with a standard deviation of 1.5-3.4 mV. The result is compared with that of pH sensitivity measurement using an Al_2O_3 layer formed by O_2 plasma.