The preparation and characteristics of LiF:Mg,Cu,P TL material are described and recent improvements are also dealt with. The reproducibility, glow curve structure and other properties of LiF:Mg,Cu,P are dependent not only on the dopant concentration and crystallisation procedure but also on the thermal treatment programme, i.e. the temperature and the time of annealing. Usually the sensitivity (light integration) of LiF:Mg,Cu,P is influenced by the high temperature peak (250 oC). The combined annealing method (270 oC/240 oC double temperatures) can significantly reduce the higher temperature peak and therefore the TL repeatability is improved. Once the optimised preparation procedure and thermal treatment are chosen, the TL sensitivity is stable with re-use. The experimental results show that LiF:Mg,Cu,P has a promising potential in routine applications, (e.g. personal and environmental monitoring for gamma radiation) especially for ultra-low dose monitoring.

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Thermal treatment of LiF:Mg, Cu, P in the range 80 - performed after typical annealing at for 10 min causes important modifications to the glow-curve structure and to the behaviour of the individual glow-peaks. The maximum glow-peak temperatures and the activation energies obtained by a glow-curve de-convolution procedure are varied as a function of pre-irradiation annealing at temperatures below . Initial rise measurements support the results obtained by the glow-curve de-convolution concerning the high values of the activation energy of glow-peak 4, as well as its variation as a function of the pre-irradiation annealing. The `prompt' isothermal decay of glow-peak 4 at temperatures just below the maximum peak temperature consists of three components instead of one, which would be expected from the kinetic models. The second component corresponds to glow-peak 4 and also presents very high E and s values. The third one corresponds to a glow-peak at the high-temperature tail of peak 4. The first component was attributed to a mechanism competitive to the mechanism responsible for the main peak 4.

LiF:Mg,Cu,P is a relatively new and very promising thermoluminescent dosemeter for low dose measurements. The dose response in linear up to 10 Gy and then it becomes strongly sublinear. The glow curve remains unaltered up to 2500 Gy, while at even higher doses the high-temperature glow peak (270 degrees C) becomes prominent. The thermoluminescence response of coarse grains (80-140 mu m) does not depend on irradiation temperature (from 77-373 K) for doses 1-25 Gy. Similarly, the thermoluminescence response of the fine grains (1-8 mu m) is independent of irradiation temperature (293-373 K) for both beta and alpha irradiation.