Synthesis of aluminum nitride thin films and their potential applications in solid state thermoluminescence dosimeters

Abstract

In this work, aluminum nitride thin films were deposited on Si (111) substrate by magnetron sputtering. The obtained film was studied for thermoluminescence after irradiating it to various doses of γ-rays. Thermoluminescence measurement showed photon emission at an irradiation dose of 100Gy or higher. Deconvolution of the experimental glow curve indicated that recombination centers in AlN were present below 2eV trap depth. Irradiated AlN films showed less than 2% fading of TL signals on storage for 1 month in dark conditions and for the same period, light induced fading was also less than 4%. A linear variation of integrated thermoluminescence counts with absorbed dose has been observed up to an irradiation dose of 10kGy. The deposited film was also characterized by grazing incidence X-ray diffraction, atomic force microscopy and secondary ion mass spectroscopy. Grazing incidence X-ray diffraction measurement of the obtained film has shown formation of polycrystalline wurtzite AlN having preferred orientation along (100) plane. Secondary ion mass spectroscopy analysis revealed the presence of oxygen in the film.