The radiation technique of selective changing of atomic composition of thin films under ion beam irradiation was designed in NRC Kurchavov Institute and was used for different nano technology applications (patterned magnetic media, metal or insulator nanowires production, etc.). The selective displacement of atoms (SDA) technique was used to displace some of nitrogen atoms in NbN (cubic, a=0.4394 nm) to oxygen atoms under composite ion beam irradiation. As a result NbNO monoclinic phase (P21/c(14), a=0.4977 nm, b=0.50217 nm, c=0.52053 nm, α=γ=90Ð¾, β=100Ð¾) was formed at 12 dpa dose range. This phase characterized with metal-type electrical conductivity at 4.2 K temperature and was used to produce integrated cryo-resistive elements. Metal phase formation was proved by electrical measurements and HRTEM structure analysis. Further increasing of the ion irradiation dose was lead to full displacement of nitrogen atoms to oxygen atoms and initial superconductive film was transformed to insulator amorphous film of Nb2O5.