Photoluminescence of Ta$_{2}$O$_{5}$ films formed by the molecular layer deposition method

Ta$_{2}$O$_{5}$ films of different thicknesses (20–100 nm) synthesized by the molecular layer deposition method on p-type silicon substrates and thermally oxidized silicon substrates have been studied by the methods of high-frequency capacitance–voltage characteristics and photoluminescence. A hole-conduction channel is found to form in the Si–Ta$_{2}$O$_{5}$–field electrode system. A model of the electronic structure of Ta$_{2}$O$_{5}$ films is proposed based on an analysis of the measured PL spectra and performed electrical investigations.