Simulation of Reactive Sputter Deposition of TiO2 Films

Abstract

The reactive sputter deposition of titanium dioxide films in Ar + O2 atmosphere is considered. The processes of
sputtering, adsorption and heterogeneous reactions are included in the model. The partial pressure of O2 molecules is
calculated as a function of the flow rate of the reactive gas, pumping speed, sputtering yields of Ti atoms and TiO2
molecules, and reaction rate constant. The dependences of concentrations of TiO2 molecules on the target and substrate
surfaces and deposition rate upon the O2 flow rate are obtained. Special attention is given to the phenomenon of
formation of a hysteresis loop. It is found that the increase of the pumping speed, chamber volume, reaction rate
constant, and sputtering yield of TiO2 molecules as well as decrease of the target surface area and sputtering yield of Ti
atoms reduce the size of the hysteresis loop.