Patent ID: 7052918

Claim:
A method for fabricating a multi-layer film for a thin film structure, the method comprising: forming an intermediate layer on a first layer having a first element; and forming a second layer on the intermediate layer, the second layer comprising a second element different from the first element, wherein the intermediate layer is comprised of both the first and second elements, wherein a concentration of the second element, in the intermediate layer, gradually varies from a portion of the intermediate layer contacting with the first layer to a portion of the intermediate layer contacting with the second layer so that the concentration of the second element is relatively high in the portion of the intermediate layer adjacent to the second layer, wherein the first layer includes an oxide or nitride material of the first element, and the first element is selected from the group consisting of aluminum, zirconium, cerium, titanium, yttrium, and niobium, wherein forming the intermediate layer includes a reaction cycle comprising: supplying a material source including the second element, over the first layer so that the material source is adsorbed to the first layer; performing a first purge process to discharge the remaining material source; supplying another material source including the first element over the first layer so that the other material source is adsorbed to the first layer or reacts with the adsorbed material source; performing a second purge process to discharge the remaining other material source and a reaction byproduct; supplying a reactant to the adsorbed material source or transformed material source by the reaction with the first layer and the adsorbed other material source so as to deposit a generated material constituting the intermediate layer; and performing a third purge process to discharge a reaction byproduct produced by the reaction with the reactant, and wherein the reaction cycle is repeatedly performed under different conditions sequentially changed for progressive repetitions of the reaction cycle, such that the compositions of materials generated by the reaction cycle are sequentially changed, whereby the intermediate layer has concentration gradation.