Production and development of implant dosimeters in radiotherapy

Scintillator materials take an effective role in medical imaging and high energy physics fields owing to their capacity of detecting high energy radiation. This kind of materials is commonly used as a dosimeter material for measurement of dose in both radiotherapy and industrial processes. In the present work, the single crystal silicon substrates were produced as an ingot by Czochralski method and prepared as wafers. Afterwards, monoclinic yttrium tantalate, yttrium tantalate niobate and rare earth doped (Dy3+, Eu3+, Tb3+, Ce3+ and Sm3+) yttrium tantalate niobate phosphor films, which are a scintillator material and used in dosimetry applications, were growth on single crystal silicon substrates by sol-gel spin coating technique. In this manner, the solutions were assessed by considering pH, turbidity, rheological and wettability properties which have an effect on these thin films. DTA-TG and FT-IR analyzes were carried out to determine the heat treatment regimens and the organic bond structures of the phosphors, respectively. The phase and elemental structure of successfully grown the films were analyzed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) devices. The morphological characteristics were determined by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The mechanical properties of these phosphors were found by nanoindentation and adhesion strength testing machines. The optical properties of the obtained phosphors were examined by time resolved photoluminescence, radioluminescence and thermoluminescence analyses. When the analyses were evaluated, the films were successfully obtained as smooth coatings at the desired phase structure. Once the luminescence properties of these phosphors are analyzed, they were found that can be used both as scintillator material and as a thermally stimulated dosimeter having long decay times.