Using a CMOS ASIC technology for the development of an integrated ISFET sensor

To take advantage of microelectronics, attempts have been made to integrate sensors in silicon and furthermore to accommodate the whole system formed of the sensor and its signal processing circuit. The major problem is the compatibility between both processes: elaboration of the sensor and integration of the measurement circuit. In this paper the authors present a method allowing industrial production of integrated ISFET sensor. An ASIC CMOS line is used to integrate the signal processing circuit; then the sensor is fabricated by a specific process that does not alter the function of the circuit.<>