RESEARCH ARTICLE Effect of annealing temperature and dopant concentration on the thermoluminescence sensitivity in LiF:Mg,Cu,Ag material Akram Yahyaabadi 1 | Falamarz Torkzadeh 2 | Dariush Rezaei Ochbelagh 3,4 | Seyed Mahdi Hosseini Pooya 2 1 Department of Physics, University of Mohaghegh Ardabili, Ardabil, Iran 2 Atomic Energy Organization, Institute of Nuclear Science and Technology, Radiation Applications Research School, Tehran, Iran 3 Nuclear Engineering & Physics Department, Amirkabir University of Technology, Tehran, Iran 4 Maad Institute of Higher Education, Shiraz, Iran Correspondence Falamarz Torkzadeh, Institute of Nuclear Science and Technology, Radiation Applications Research School, Atomic Energy Organization, Tehran, Iran. Email: ftorkzadeh@aeoi.org.ir Abstract LiF:Mg,Cu,Ag is a new dosimetry material that is similar to LiF:Mg,Cu,P in terms of dosimetric properties. The effect of the annealing temperature in the range of 200 to 350°C on the thermoluminescence (TL) sensitivity and the glow curve structure of this material at different concentrations of silver (Ag) was investigated. It has been demonstrated that the optimum values of the annealing temperature and the Ag concentration are 240°C and 0.1 mol% for better sensitivity, respectively. The TL intensity decreases at annealing temperatures lower than 240°C or higher than 240°C, reaching a minimum at 300°C and then again increases for various Ag concentrations. It was observed that the glow curve structure altered and the area under the low temperature peak as well as the area under the main dosimetric peak decreased with increasing annealing temperature. The position of the main dosimetric peak moved in the direction of higher temperatures, but at 320 and 350°C annealing temperatures, it shifted to lower temperatures. It was also observed that the TL sensitivity could partially be recovered by a combined annealing procedure. KEYWORDS annealing, Cu,Ag, LiF:Mg, sensitivity, thermoluminescence 1 | INTRODUCTION LiF:Mg,Cu,P is one of the most popular thermoluminescence (TL) material owing to its high sensitivity and tissue equivalence. [1–3] Consequently, intensive studies on the effect of thermal treatments on the TL properties of this dosimeter have been carried out in recent years. Yang et al., [4,5] Tang et al., [6–8] Meijvogel and Bos, [9] Oster et al., [10] Chandra et al., [11] Bilski et al. [12] and Cai et al. [13,14] suggested that annealing of LiF:Mg,Cu,P at temperatures above 240°C leads to the loss of sensitivity, a shift of the main peak towards higher temperature and changes in the glow curve. Mckeever [15] stated that the causes of the changes after thermal treatments are unclear. He noted that, it is unknown whether these changes are associated with changes in the trap structure or related to changes in the emission characteristics. Cai et al. [13] suggested that the decrease in TL intensity of the LiF:Mg,Cu,P material is induced by the thermal damage to traps. Chen and Stoebe [16] reported that in the annealing temperatures greater than 240°C, the copper (Cu) valency in the LiF:Mg,Cu,P sample changed from Cu + to Cu 2+ . However, many researchers have offered special techniques to reverse the TL sensitivity. Meijvogel and Bos [9] reported that the degradation of TL intensity from the annealed sample at temperatures above 240°C could not be fully restored by repetitive standard annealing procedure. Yang et al. [4,5] suggested that a partial recovery of the sensitivity and restoration of the dosimetric peak position could be observed at an annealing temperature of 330 to 700°C. However, Tang et al. [6–8] suggested that the thermal loss of the TL intensity and the variation in the glow curve structure could be fully restored by annealing at very high temperature in a nitrogen gas atmosphere followed by a combined annealing procedure. Therefore, there may well be a need to develop new material that has the valuable properties of LiF:Mg,Cu,P and eliminates its Abbreviations used: Ag, silver; FT‐IR, Fourier transform infrared; TL, thermoluminescence; XRD, X‐ray diffraction. Received: 8 December 2016 Revised: 23 September 2017 Accepted: 22 February 2018 DOI: 10.1002/bio.3487 Luminescence. 2018;1–6. Copyright © 2018 John Wiley & Sons, Ltd. wileyonlinelibrary.com/journal/bio 1