Characterization of fading of a MOS-based sensor for occupational radiation dosimetry

Herein, we study the stability over time after irradiation ('fading') of our recently-presented sensor for occupational radiation dosimetry. This accumulating radiation sensor, suitable for the measurement of low-dose, long-term exposure, is a custom MOS capacitor that traps holes generated by ionizing radiation. The resulting shifts in the capacitance-voltage curves are recorded and used for the dose level determination. The dose level accuracy is paramount to the sensor's reliability, and thus the fading characteristics need to be characterized. A variety of environmental and bias conditions were applied and fading was studied for over 2200 hours after irradiation.