30th September 2021

“Tuning” Perpendicular Magnetic Anisotropy

Magnetic multilayers yielding perpendicular magnetic anisotropy (PMA) are key components for emerging spin-electronic technologies, such as magnetoresistive sensors for ultra-low biomagnetic signal detection or non-volatile magnetic memory devices for neuromorphic computing and artificial intelligence applications. You can read how scientists at Empa, University of Basel and Evatec have been able to control the  magnetic properties of [Co(0.4 nm)/Pt(0.7 nm)] multilayers by controlling the sputtering voltage during growth of cobalt layers by a facing target cathode. It is shown that increasing sputtering voltage up to 150 V leads to an improved crystalline texture and this results in larger magnetic anisotropies together with increased out-of-plane coercive fields. At a higher cathode voltage of 540 V, however, crystalline texture quality slightly worsens and this is accompanied by a decrease in the effective anisotropy. Using facing target cathode sputtering, the crystalline structure of the multilayers can be controlled without applying any heat treatment and this can be utilized to optimize the magnetic properties of Co/Pt multilayers for specific applications. 

For free access the full paper published in Science Direct click here.