A solution growth system has been built based on temperature reduction method [1]. A few KDP crystals were grown by the system up to 160×40×38 mm dimensions. Spectrophotometer transmission spectra from (100) planes of the grown crystals show about 86 % transmission in the visible region. XRD analysis, laser damage threshold, and microhardness of the crystals were determined. The etching behavior of surface features of grown KDP single crystals was studied in different etchants.

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Improvement of crystal performance is important for the nuclear instrumentation, medical imag ing and radiation measurement as industrial application. For achieving this aim, we developed to establish crystal growth process and design and fabricate crystal growth equipment. Finally, the single crystal scintilla tor of NaI (Tl) was grown successfully by the conventional Czochraski method and Thallium quantity was measured through grown crystal. The results showed Thallium losses by evaporation during crystal growth. Thus, the first part of grown NaI(Tl) (2.5 cm) has high light yield and is suitable for counter. The character istics of the grown NaI(Tl) were evaluated on the excitation, emission responses. Finally, grown crystal was used as scintillators in nuclear radiation detection, industrial applications and etc.

A single crystal and 5 polycrystalline samples of LiF:Mg, Ti and their pellets were prepared and investigated so as to apply thermoluminescence high gamma dose dosimetry. Three zones of single crystal with dopant concentrations of 200 ppm of Mg and 20 ppm of Ti were also used to prepare the single crystal samples. For polycrystalline samples, dopant concentrations of 0.062 mol% Mg and Ti concentrations in the range of 0.016 and 0.046 mol% were used. All the samples were exposed to gamma doses of 1 kGy to 700 kGy and their response changes were determined by a gamma dose test of about 60 mGy. According to the results obtained, the use of response reduction by curve-fitting up to about 300 kGy can be performed reliably for high dose gamma dosimetry.