Floating Gate Dosimeter Characterization for Space Applications

The radiation environment in space can pose a serious risk to both humans and space systems. Widespread and continuous monitoring of this environment is essential to mitigate risks associated with radiation exposure. Miniaturization and use of commercial-off-the-shelf components have enabled significant advances in space technology. These trends can be leveraged to develop innovative radiation sensing and monitoring technologies. However, dosimeters that can effectively measure radiation levels while minimizing their impact on size, power, mass, and cost are required. Floating gate dosimeters (FGDOSs) possess these characteristics, but rigorous testing is needed to ensure their accuracy in spacecraft applications. In this study, we conducted an extensive characterization campaign for an FGDOS chip using a proton beam, increasing the available information on the sensor. The behavior of the dosimeter with respect to resolution, dose rate, beam energy, total ionizing dose (TID), power consumption, annealing, temperature, and single-event effects (SEEs) was experimentally studied. Notably, we observed a previously unseen phenomenon, which we termed 'frequency surge' (FS). This phenomenon is likely to have implications for the dosimeter's performance under real spacecraft conditions. Our findings show that the dosimeter is able to combine small power consumption with high dose resolution but also highlight the need for testing against other radiation source types and intensities.