Ion beam sputtering [31] and electron beam/thermal coevap-oration [32] were also utilized. In brief, the films were grown using electron beam sources to evaporate the metals (La, Sr, and Mn usually). By carefully controlling the proper atomic raion of the metal, one can make films with various compositions. In molecular beam epitaxy, O'Donnel et al. [33] used a block-by-block (BBD) technique, and the films are often oxidized with ozone. This method is remarkably suitable for depositing perovskite oxide films (complex quaternary compounds) of high quality. Briefly, a sequential deposition of separate blocks of the pure elements is used to form each layer of the growing film. In the case of La0 67Ca033MnO3, the sequence begins with Ca, followed by La, and lastly Mn this particular sequence has been selected so as to avoid the intermediate formation of others phases (calcium manganese oxides and lanthanum manganese oxides).

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