Modeling and experiments of N-doped vanadium oxide prepared by a reactive sputtering process

An original numerical model, based on the standard Berg model, is used to simulate the growth mechanism of N-doped VO_x deposited with changing oxygen flow in the reactive gas mixture. In order to compare with the numerical model, N-doped VO_x films are prepared by reactive magnetron sputtering from a metallic vanadium target immersed in a reactive gas mixture of Ar+O₂+N₂. Both experimental and numerical results show that the addition of N₂ to the process alleviates the hysteresis effect with respect to the oxygen supply. Film compositions obtained from the XPS analysis are compared to the numerical results and the agreement is satisfactory. The results also show that the compound of VN is only found at very low O concentration because of the replacement reaction of VN by O₂ atoms with higher oxygen flow rate.