Koval V. The nanocrystalline silicon thin films, doped with europium and yttrium, for optoelectronics

Work is devoted to development of technology of nanocrystalline silicon thin films, doped with europium and yttrium, and also heterojunction on their base for optoelectronics. The design of influence of nanocrystallites and rare-earth dopants on band structure and material's electroconductivity was carried out, also it was shown their influence on photosensitive characteristics of photoreceivers that provided the theoretical base in search of suitable technological conditions. By means of structural and chemical methods of material's study it was found relation of film's nanostructure and chemical composition with technological parameters. In the work it was found that electroconductivity and photosensitivity of nanocrystalline silicon thin films increases with growth crystalline fraction in material, while increase in UV-sensitivity is observed with decreasing of nanocrystallite size. It was shown the increasing of electroconductivity, photo- and UV-sensitivity in silicon thin film under condition of rare-earth metals incorporation. Also the influence of rare-earth dopants on photo-EMF of heterojunctions on the base of nanocrystalline silicon thin films was studied in this work. It was proposed the technology, in which photosensitivity and UV-sensitivity of photoresistors and photodiodes as well as effectiveness and stability of photovoltaic converters reaches the maximum values.