Electret Production and Applications with Special Regard to Health Physics Dosimetry: A Review

An electret detector is a piece of dielectric material film charged or polarized by a specific charging method to induce a quasi-permanent electric field. Electret films perform unique characteristics for production and applications in many areas of science and technology, especially in health physics dosimetry. A charged electret detector, when placed in an ionized environment, collects negative or positive ions depending on its original charging state, which reduces its original charge. The number of charges reduced in the ionized field is usually proportional to the absorbed radiation dose. In this paper, the state-of-the-art information on the type of electrets, production methods, some applications in particular in health physics dosimetry, and relevant concepts are reviewed.