Radiation dosimetry in medicine using II-VI semiconductors

Abstract

For several decades, radiation detection has been implemented using mainly silicon (Si) and germanium (Ge). However, group II-VI compound semiconductors such as cadmium telluride (CdTe), cadmium sulfide (CdS), cadmium selenide (CdSe), zinc selenide (ZnSe), zinc oxide (ZnO), zinc sulfide (ZnS), and zinc telluride (ZnTe) have been recently investigated extensively as alternative radiation detectors. Different studies have explored these semiconductors for radiation detection in diagnostic radiology, radiation oncology, nuclear medicine, and non-medical fields such as astronomy. This article aims at demonstrating that II-VI semiconductors are potential and alternative medical radiation detectors, based on the current studies. II-VI semiconductor dosimetry mechanisms and compliance to desirable dosimetry characteristics (e.g., linearity of detector signals to the radiation doses, precision, radiation hardness, and sensitivity not depending on beam energy, dose, dose rate, and irradiation angle) are presented and discussed. Additionally, the performances of II-VI-based detectors applied for dosimetry in mainly diagnostic radiology, radiation oncology, and nuclear medicine are evaluated. Eventually, the dose, dose rate, and energy ranges applicable to the II-VI-based detectors herein are recapitulated. II-VI semiconductors are promising radiation detectors because they comply to the preferred dosimetric metrics as per the current literature. Nevertheless, there is still need for more research to further (a) characterize II-VI semiconductors for medical radiation dosimetry, and (b) compare II-VI semiconductor detectors to conventional detectors. Additionally, more II-VI semiconductor detectors should be commercialized to increase the availability of these detectors on the medical dosimetry market.