Titanium oxide thin films stoichiometric composition dependence on the oxygen flow at magnetron sputtering

Abstract The aim of this work is to study the effect of the partial pressure of oxygen in the magnetron sputtering chamber on the stoichiometric composition of titanium oxide films synthesized by this method. Titanium oxide films were synthesized at a partial oxygen pressure from 44 to 68 mPa. An increase in the partial pressure of oxygen in the chamber led to a decrease in the titanium / oxygen ratio from 0.91 to 0.51 and an increase in the resistivity from 4 to 70,000 Ω cm. The authors developed a thermodynamic model that allows us to predict the stoichiometric composition of films depending on the conditions of their deposition. This theoretical model describes the experimental results well. It allows one to estimate the stoichiometric composition of the film when the discharge parameters (high-frequency power) and the partial pressure of oxygen in the reactor are known, which can be set by the gas flow. The change in the resistivity of thin films is associated with the probability of the occurrence of hopping conduction over the electronic states of an oxygen vacancy.