Preparation and dosimetric properties of a highly sensitive LiF thermoluminescent dosimeter

Highly sensitive phosphors for the measurement of low radiation doses are needed for environmental thermoluminescent dosimetry. Improvement of the sensitivity of LiF by doping with additional impurities was studied and the preparation of LiF(Mg, Cu, P), LiF(Mg,Cu,B) and LiF(Mg, Cu, Si) is described. The sensitivity of some phosphors relative to that of Harshaw TLD-100 LiF was measured. The newly produced phosphors were all more sensitive than TLD-100; in particular the sensitivity of LiF(Mg,Cu,P) was found to be 23-25 times greater than that of TLD 100, and comparable to that of CaSO4(Tm) and Mg2Si04(Tb) which can measure about 100 μrad. Investigations of the effects of thermal treatment and of mechanical stress showed that if treated under suitable thermal conditions LiF(Mg, Cu, P) can be re-used and that dose estimation will scarcely by affected by triboluminescence.(author)