Vovk Y. Processes of the charge carriers transport and capture in the heterosystems amorphous film - crystalline silicon

In the dissertation work are investigated the mechanisms of transport and capture of charge carriers in heterosystems a-Si:H(Er)/c-Si, SiO2(Ge)/c-Si and a-SiC/c-Si, mechanism of electroluminescence (EL)in heterostructure a-Si:H(Er)/c-Si, and also the influence of low-temperature HF plasma treatment on electrophysical and optical properties heterosystems SiO2(Ge)/c- Si and a-SiC/c-Si. As a result of the conducted investigations were established the mechanisms of the transport of charge carriers in heterosystems a-Si:H(Er)/c-Si, SiO2(Ge)/c-Si and a-SiC/c-Si, it is shown that in the case of heterostructures a-Si:H(Er)/c-Si and a-SiC/c-Si the current is defined by both the electrons and by holes. Based on a study of the processes of current flow and deep levels, which appear in the forbidden band of film a-Si:H with the introduction of Er atoms, is built the model of EL excitation in heterostructure a-Si:H(Er)/c- Si, which consists in capture and recombination of charge carriers on the electron-hole states, with energies Ec-0.55 eV and Ev+0.40-0.44 eV, located near erbium-oxygen complex, with the subsequent resonance energy transfer to the electron, which is located on the inner shell of the erbium ion. Is for the first time demonstrated the possibility of an essential improvement in the operational stability of the EL devices on basis of SiO2 layer, which contain Ge nanoclusters with the aid of the low-temperature HF plasma treatment. Furthermore, it is shown that the low-temperature HF plasma treatment leads to an essential improvement in the ohmic resistance of contact Al/a-SiC