Field effect SnO2 nano-thin film layer CMOS-compatible
The integration of metal oxide gas sensing layers into CMOS electronic still is a challenge especially due to the high operating temperatures that do not comply with silicon transistor limits and, even more critical, metal oxide annealing temperatures. External electric fields will allow control over the energy levels of the sensing layer and thus over adsorption sensitivity, consequently the interaction between gas and sensitive layer is modulated. As the absorbed gas on the surface produces an band bending, it changes conduction paths allowing gas detection through resistance measurements. With this configuration, field switch offers fast desorption and thus handling of low temperature response times. Also electric fields may be useful to reduce annealing temperatures. In this paper some aspects as design, measurements and models are studied.