Advances in transition metals and rare earth elements doped ZnO as thermoluminescence dosimetry material

The numerous benefits like smaller size, easy handling, quicker readouts and cost effectiveness render TLDs as prominent radiation dose measuring instruments. Zinc Oxide (ZnO) is well recognized among these TLD materials due to its remarkable post exposure glow properties. Moreover, along with reasonable TL properties it inherently shows good mechanical and chemical stability, non-toxic and non-hygroscopic nature. However, in comparison to its contemporaries it lacks in sensitivity when exposed to low radiation doses and exhibits moderate fading effects. These draw backs stem from ZnO electronic nature i.e. availability of low number of radiation responding electrons along with trapping centers which can retain these electrons and are responsible for thermal assisted glow curve. One of the solutions is doping it with high atomic number metallic ions. Transition metals (TM) and rare earth (RE) elements doped ZnO materials show promising results i.e. doped ZnO shows improved TL response i.e. more linearity, better stability and less fading. As TM and RE doped ZnO appears to be promising TLD materials, this review provides an overview of research on TL characteristics of TM and RE doped ZnO materials.