Preparation and characterization of a room temperature magnetic semiconductor CoFeTaBO

Abstract

The structural, electrical and magnetic properties of a new semiconductor material Co-Fe-Ta-B-O are investigated. The preparation of the material is a new try to make magnetic semiconductor, which introduces a semiconducting element to a ferromagnetic metal for realizing the semiconductivity and ferromagnetism. The material exhibits an amorphous structure, and combines electrical, optical and magnetic properties simultaneously. The room temperature resistivity of Co21.9Fe16.2Ta7.9B21.4O32.6 is about 15, belonging to the typical range of semiconductors. Meanwhile, it has good optical transparency in the visible and near-infrared region, giving a direct bandgap of 3.3 eV by Tauc plot method. Moreover, the material preserves the original ferromagnetism of the metal with a Curie temperature higher than 400 K, which makes sense for the application of magnetic semiconductor. This new try opens a way to design the novel magnetic semiconductor with desirable properties, and probably will extend their application to a wide variety of electronic devices.