Interfacial structure of ferromagnetic Fe-Pt thin films grown on a Si substrate

Abstract

In order to understand the Fe-Pt phase transformation, Fe-Pt films were sputtered on HF-treated, untreated Si substrates, and SiO 2 substrates and the magnetic and structural properties were analyzed by XRD, VSM, and XPS. The formation of Pt 2Si on the interface between Fe-Pt films and a Si substrate could be clearly observed with a shift of Pt4f 7/2 binding energy. Native oxide on the surface of Si substrate slowed the transformation of the disordered Fe-Pt phase to the ordered phase. The Pt 2Si phase was easily formed during sputtering on an HF treated Si substrate; moreover, a formation of a very small amount of Pt 2Si phase could be observed on the interface of Fe-Pt films and a SiO 2 substrate. Thus, the formation of Pt silicide assumes an important role in the transformation of Fe-Pt films grown on Si substrates.