Parylene HT Electrets Charge Stability Analysis at High Temperatures

Embedded charges in electrets independently generate electric fields, offering a potential solution for mitigating partial discharge and space charge injection and accumulation in insulating systems. In our previous study, we demonstrated that electrets prevent partial discharge and space charge injection and accumulation under applied square voltage pulses, as well as in high-temperature and low-pressure environments. However, the charge retention behavior of electrets in these conditions remains unexplored. In this study, we investigate the impact of temperature, thickness, and charging duration on the charge stability of Parylene HT electrets. Parylene HT electrets were fabricated using the triode corona charging method, and the embedded charges were measured using an electrostatic voltmeter. The charge decay in electrets was continuously monitored for up to 30 hours.