Development of LiF:Mg,Cu,Si TL material (new KLT-300) with a low-residual signal and high-thermal stability

Abstract

LiF-based thermoluminescence (TL) materials have been widely used for radiation dosimetry due to their attractive features. LiF:Mg,Cu,P is one of the most sensitive tissue-equivalent TL materials, approximately 40 times more sensitive than LiF:Mg,Ti (TLD-100), but it has two main drawbacks: a thermal loss of the TL sensitivity when annealed at temperatures>240 degrees C, and a relatively high-residual signal. Recently, LiF:Mg,Cu,Na,Si TL material was developed to overcome these drawbacks at the Korea Atomic Energy Research Institute, but it provided only marginal improvements in reducing the residual signal. The newly developed LiF:Mg,Cu,Si TL material has a significantly lower residual signal and a better stability to thermal treatments. In this article, the preparation method and some dosimetric properties (sensitivity and residual signal) of the new LiF:Mg,Cu,Si TL material are presented. At the end of the preparation procedures, a dual-step annealing method is introduced and this has proved as a very efficient method to reduce the high-temperature peak and is the cause of residual signal. Therefore, the high-temperature peak in the glow curve was significantly reduced. The sensitivity is approximately 20 times higher than that of TLD-100 and the residual signal was estimated to be approximately 0.04%.

Thermoluminescent Phosphors for Radiation Dosimetry

“…Subsequently, Lee et al [77][78][79] reported dosimetric characteristics of a new LiF:Mg,Cu,Si thermoluminescent (TL) material developed at KAERI, Korea and compared with those of commercially available LiF:Mg,Cu,P (GR-200A)(China). It is reported that LiF:Mg,Cu,Si thermoluminescence dosimeter (TLD) can be heated up to 573 K without any loss of TL sensitivity or any change in the glow curve structure.…”

“…et al[60,61], Wu et al[62], DeWerd et al[95], Bhatt et al[27,96], Wang et al[63,64], Driscoll et al[ 52], Prokic and Botter-Jensen[23], Zha et al[24], Pradhan and Bhatt[97], Mahajna et al[85], Bilski et al[87,89], etc.. LiF:Mg,Cu,Na,Si and LiF:Mg,Cu,Si TL phosphors have been characterised by Nam et al[72], Jung et al[73], Lee et al[74], Tang et al[75,76], Lee et al[78,79], Kim et al[25], Rahman et al[80] and Tang et al[82,83].…”

Dosimetric Properties of the Newly Developed LiF:Mg,Cu,Si TL Material

“…Annealing temperature and time are used to produce the lowest intrinsic background and to obtain the highest efficiency [7]. The details of the preparation procedure can be found elsewhere [8].…”