Growth and Optical Characterisation of Lithium Fluoride Films for Proton Beam Detectors
Maria Aurora Vincenti, Mauro Leoncini, Stefano Libera, Enrico Nichelatti, Massimo Piccinini, Alessandro Ampollini, Luigi Picardi, Concetta Ronsivalle, Alessandro Rufoloni, Rosa Maria Montereali
Abstract. Polycrystalline LiF thin films were grown by thermal evaporation on glass, fused silica (Suprasil) and Si(100) substrates in controlled conditions. Starting from the measured specular reflectance and direct transmittance spectra, some physical parameters of the LiF films grown on fused silica substrate were determined by using a best-fit procedure. The LiF films grown on glass and Si(100) substrates were irradiated by proton beams of 27 MeV nominal energy produced by a pre-clinical linear accelerator at several doses in the range between 4.2103 and 1.7105 Gy. Substrate-enhanced photoluminescence intensity was observed in coloured LiF films grown on Si substrates with respect to LiF films deposited on glass in the same deposition run. This behaviour is mainly ascribed to the reflective properties of the Si substrate in the visible spectral range, where the absorption and emission bands of F2 and F3+ CCs are located, although other complex effects due to the polycrystalline nature of the films cannot be excluded. Further systematic studies are under way.
Keywords
Lithium Fluoride, Thin Films, Colour Centres, Photoluminescence, Radiation Detectors
Published online 2/25/2020, 9 pages
Citation: Maria Aurora Vincenti, Mauro Leoncini, Stefano Libera, Enrico Nichelatti, Massimo Piccinini, Alessandro Ampollini, Luigi Picardi, Concetta Ronsivalle, Alessandro Rufoloni, Rosa Maria Montereali, Growth and Optical Characterisation of Lithium Fluoride Films for Proton Beam Detectors, Materials Research Proceedings, Vol. 16, pp 56-64, 2020
DOI: https://doi.org/10.21741/9781644900710-7
Part of the book on Photonics and Photoactive Materials
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