SiCxNy:Fe films as a tunable ferromagnetic material with tailored conductivity

Abstract

Amorphous ferromagnetic materials with variable composition are promising candidates for application in rapidly-growing technological fields, such as spintronics. However, the significant downside of current state-of-the-art materials is a conductivity mismatch between the injector and the semiconductor, which often is associated with the inability to control and precisely tailor the magnetic properties and conductivity. We report on the synthesis of soft-magnetic SiC_xN_y:Fe films with a saturation magnetization of 20 emu cm⁻³ and a conductivity similar to the one of Si, which is crucial for possible applications. XRD with synchrotron radiation and EXAFS revealed the complex composite structure of the films: crystals of Fe₃Si, Fe₅Si₃, SiC and graphite are embedded into the amorphous matrix of SiC_xN_y. Variation of the deposition conditions allowed us to separately control the magnetic properties through the iron concentration and the conductivity of the material through the amorphous SiC_xN_y matrix composition. The reported results revealed significant potential of SiC_xN_y:Fe films as a prospective object for analysis of spin-polarized transport in amorphous semiconductors and for application in the field of spintronics.