[5p-C18-1~7] 10.1 新物質・新機能創成（作製・評価技術）

▲ [5p-C18-7] Perpendicular magnetic anisotropy of polycrystalline Fe/MgO interfaces induced by W buffer and Tb capping layers.

〇(M2)Yuki Iida^1,2、Jun Okabayashi³、Seiji Mitani^1,2 (1.Univ. of Tsukuba、2.NIMS、3.The Univ. of Tokyo)

キーワード：spintronics, PMA, Fe/MgO

Polycrystalline Fe/MgO layered structures were prepared with amorphous W buffer and Tb capping layers. Perpendicular magnetic anisotropy of 0.25MJ/m³ was obtained by post-annealing for the present boron-free stacks of W/Fe/MgO/Tb with the Fe layer thickness of 1.0 nm, while boron atoms play a key role to PMA for conventional CoFeB/MgO layers. The amorphous W buffer can cause non-crystalline growth of Fe layer, and x-ray absorption spectra suggest that the Tb capping absorbs excess oxygen at the Fe/MgO interface. Orbital moment anisotropy, which was controlled by the presence of Tb layer, was also observed for the Fe layers. The present layered structure can be a useful alternative to study interface PMA.