Effects of B and C doping on tunneling magnetoresistance in CoFe/MgO magnetic tunnel junctions

Article

关键词: THIN-FILM;    COFEB;    1ST-PRINCIPLES;    CONDUCTANCE;   

DOI  :  10.1103/PhysRevB.98.045129

来源: SCIE

【 摘 要 】

Using density-functional theory calculations, we investigate the dominant defects formed by boron (B) and carbon (C) impurities in a CoFe/MgO/CoFe magnetic tunnel junction (MTJ) and their influence on conductivity and tunneling magnetoresistance (TMR). We find that, in the O-poor conditions relevant to experiment, B forms the substitutional defect B-Co and C forms the interstitial site C-i at the CoFe/MgO interface. The C-doped MTJ is predicted to have a significantly higher TMR than the B-doped MTJ. This is due to interface state densities associated with the majority spin Delta(1)-symmetry bands being more heavily suppressed by the B-Co defects than by the Ci defects. Our results indicate that carbon can serve as a viable alternative to boron as a dopant for MTJ fabrication.

【 授权许可】

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