Simulation of a Floating Gate device fabricated in standard CMOS technology for dosimetry applications

The use of floating gate devices for storing digital information is well known. More recently, these devices have been proposed for analogue applications and for use in radiation detection. In this case, the charge generated in the SiO2 due to the ionizing radiation is collected by the floating gate by virtue of the electric field generated by the charge stored in it. This in turn changes some electrical characteristics of the device that can be measured and referred to the absorbed dose of ionizing radiation. A comprehensive device simulation that includes the process of charging the floating gate via tunnelling and the mechanism of charge collection from the SiO2 has been carried out using the process parameters of a standard CMOS 0.18μm technology. The results suggest that this device could be used as a sensitive integrated dosimeter that allows the fabrication of the readout electronics on the same silicon chip.