Fomovskyi F. Technologies for improvement of degradation stability of GaAs, Si crystals, structure and devices and their base

In the work the technologies for improvement of degradation stability of semi-insulating gallium arsenide crystals, silicon nanostructures, and solar modules based on silicon solar cells were developed. For the first time, the method for improvement of degradation stability of semi-insulating gallium arsenide crystals against action of RF and thermal treatments was proposed. The method is based on application of preliminary plasma treatments those form partially relaxed surface layer. The layer can getter defects from the crystal volume during the further treatments. It was also shown that the plasma treatment of semi-insulating gallium arsenide crystals compensated with tellurium allows us to improve their degradation stability against action of RF and microwave treatments. However, untreated samples of such type degrade substantially lower compared to the untreated samples compensated with chromium and degradation stability of the treated crystals depend on duration of the plasma treatment. Optical properties of silicon nano-clusters in dielectric matrix were studied and it was shown that due to deposition of diamond-like carbon films the nanostructures degradation stability may be improved. Correlation between structural perfection of thin subsurface layer in "solar" silicon, value of internal mechanical stresses in its and recombination properties of the materials was found. Correlation between structural perfection of thin subsurface layer in "solar" silicon, value of internal mechanical stresses in its and recombination properties of the materials was found. The technology of solar module encapsulation with using of two-component organo-silicon sealants was modernized. It was also shown that application of the sealants together with panted polymer composites allows us to improve the photo-energetic characteristics of solar cells, modules, and batteries owing to more effective utilization of short wavelength part of the solar spectrum.