| 摘要 |
PROBLEM TO BE SOLVED: To promote large storage capacity of a storage device while enhancing the operation stability thereof, by enhancing thermal stability of STT-MRAM storage elements furthermore, and allowing further miniaturization of the storage elements.SOLUTION: In an STT-MRAM storage element having a multi-layered ferri-pin structure where a magnetization fixed layer consists of a ferromagnetic layer and a non-ferromagnetic layer of at least two layers, the magnetic material in contact with an insulating layer in the magnetization fixed layer is composed of a CoFeB magnetic layer, the magnetic material not in contact with an insulating layer in the magnetization fixed layer is an alloy or a lamination structure using at least one kind of Pt group metal elements and ferromagnetic 3d transition metal elements out of 3d transition metal elements, respectively. Atomic concentration of the Pt group metal element is lower than that of the ferromagnetic 3d transition metal element. Consequently, multi-layered ferri-bonding strength is enhanced, and thermal stability of the storage element can be enhanced. |
