To develop a high-quality Weyl magnet Mn3Sn thin film, polycrystalline Mn-Sn was sputter deposited onto an fcc or hexagonal close-packed metallic seed layer of Pt, Cu, Ir, Ru, Cr, or Al. Among the tested seed materials, Pt and Cu enabled fabrication of highly c-plane oriented textured D019-type Mn3Sn films with a smooth surface (mean roughness below 0.3 nm) after postannealing at 350°C or below. The Mn3Sn films exhibited substantial signals of the anomalous Nernst effect (ANE), which is one characteristic of a Weyl magnet. Microstructural analysis revealed that the Cu seed layer significantly diffused into the Mn3Sn layer during postannealing, while the Pt seed layer changed little. The results suggested that a small amount of Cu mixture (up to 2.5 at. %) did not degrade the ANE signal but effectively lowered the postannealing temperature to form the D019 structure. The developed films and techniques are beneficial for antiferromagnetic spintronics in terms of the smoothness and process consistency in a standard process for magnetic random-access memory.
ASJC Scopus subject areas
- Materials Science(all)
- Physics and Astronomy (miscellaneous)