Magnetic Tunnel Junctions with W Layers.

Magnetic Tunnel Junctions with Perpendicular Magnetic Anisotropy are promising candidates for next generation of magnetic random access memories. Room-temperature tunneling magnetoresistance behavior has been analyzed in CoFeB/MgO/CoFeB perpendicular magnetic tunnel junctions with different buffer layers for annealing at 340\textdegree C and 380\textdegree C. Transport properties have been studied in these junctions. The TMR rapidly increased to a maximum within the first few minutes, up to 135{\%}, followed by a steady decline afterwards. These results highlight the importance of proper buffer/capping layer in perpendicular tunneling junction.