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arXiv · 2407.07716

Influence of buffer/protective layers on the structural and magnetic properties of SmCo films on Silicon

F. Maspero·O. V. Koplak·A. Plaza·B. Heinz·F. Kohl·P. Pirro·R. Bertacco
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Abstract

Integration of Samarium Cobalt hard magnets on silicon requires buffer/protective layers that can enhance the magnetic properties of the magnet while preserving its structure and chemical composition after post-annealing treatments needed for the formation of the magnetically hard phase. In this work, a comparison of Samarium-Cobalt films for five different buffer/protective layers, namely Ti, W, TiW, Ta, Cr and two different annealing temperatures, 650{\deg}C and 750{\deg}C, is presented. Depending on materials and annealing temperatures, magnetic properties such as saturation and coercivity of the SmCo film can be finely tuned. We show that coercivity up to 3.65 T or saturation magnetization up to 0.95 T can be reached by proper choice of the relevant process parameters: deposition temperature, material for the buffer/protective layer and annealing temperature. Such value of coercivity is among the highest found in literature for thin films of SmCo.

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F. Maspero, O. V. Koplak, A. Plaza, B. Heinz, F. Kohl, P. Pirro, R. Bertacco. 2024-07-10. Influence of buffer/protective layers on the structural and magnetic properties of SmCo films on Silicon. https://arxiv.org/abs/2407.07716

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