Cobalt (co) and platinum (pt)-based multilayer thin film having inverted structure and method for manufacturing same

Abstract

The present invention relates to a cobalt (Co) and platinum (Pt)-based multilayer thin film having a novel structure and perpendicular magnetic anisotropy, and to a fabrication method thereof. More specifically, the invention relates to a cobalt and platinum-based multilayer thin film having perpendicular magnetic anisotropy (PMA), which includes thin cobalt layers and thin platinum layers alternately deposited over a substrate, and has an inverted structure in which a thickness of the thin cobalt layers is greater than that of the thin platinum layers, and to a fabrication method thereof. The cobalt and platinum-based multilayer thin film has a new structure in which the thickness of a magnetic thin layer is greater than that of a non-magnetic thin layer. The multilayer thin film may be easily applied as a free layer and a pinned layer in a magnetic tunnel junction by controlling the perpendicular magnetic anisotropy energy depending on the thickness ratio of the layers. Also, the multilayer thin film has excellent thermal stability, and thus maintains its PMA energy density even after being subjected to a heat treatment process. In addition, it enables a fine amount of in-plane magnetic anisotropy to be formed by heat treatment so as to reduce the critical current density required for magnetization switching. Therefore, it may be advantageously used for high-performance and high-density MRAM.