TABLE OF CONTENTS Zirconia has very much attracted the attention of technologists and scientists owing to its combined electrical, chemical, optical and mechanical characteristics. All these properties make this material suitable for a large variety of applications, On the other hand, a little research has been done on its luminescent properties [1,2,3,4,5,6,7,8,9,10,11,12,13,14].
In order to obtain material suitable for thermoluminescence dosimetry, Zirconium TL phosphors have been synthesized by blending zirconium oxichloride (ZrOCl:8H 2O by Merck) and ethhyl alcohol. This solution is stirred for 15 minutes, then heated at 250 C for 30 minutes until full evaporation of the solvent. The amorphous powder is then submitted to different thermal treatments in an oxiding atmosphere (air) in order to stabilize the trap structure. Then the powder is crushed and sieved to select grains having a size between 100 and 300 . Sinterd ZrO 2+PTFE pellets of 5 mm in diameter and 0.8 mm in thickeness can also obtained.
The most attractive feature of ZrO 2 phosphor is its very high intrinsic sensitivity to UV radiation. The typical glow curve of ZrO 2, after UV irradiation, exhibits one single peak at 180 C.
After beta irradiation from 90Sr/ 90Y source, the glow curve presents two resolved peaks at 200 C and 250 C respectively. The TL response is linear from 2 to 60 Gy; the reproducibility, over several repeated cycles of annealing, irradiation and readout, is better than 1.8% and fading at room temperature is 3.8% in one month.
