Ion plasma deposition of oxide films with graded-stoichiometry composition: Experiment and simulation

Abstract

A method of ion plasma deposition is proposed for obtaining thin multicomponent films with continuously graded composition in depth of the film. The desired composition–depth profile is obtained by varying the working gas pressure during deposition in the presence of an additional adsorbing screen in the drift space between a sputtered target and substrate. Efficiency of the proposed method is confirmed by Monte Carlo simulation of the deposition of thin films of Ba_xSr_1–xTiO₃ (BSTO) solid solution. It is demonstrated that, during sputtering of a Ba_0.3Sr_0.7TiO₃ target, the parameter of composition stoichiometry in the growing BSTO film varies in the interval of x = 0.3–0.65 when the gas pressure is changed within 2–60 Pa.