Growth of Nitride-Based Fe_3N/AIN/Fe_4N Magnetic Tunnel Junction Structures on Si(111) Substrates

摘要

We have fabricated nitride-based Fe_3N(30 nm)/AIN(2 nm)/Fe_4N(25 nm) magnetic tunnel junctions (MTJs) structures on Si(111) substrates by molecular beam epitaxy of Fe_3N layers onto AIN/α-Fe/Si(111). The X-ray diffraction peaks of α-Fe disappeared after the growth of the Fe_3N layer, and those of Fe_4N appeared instead. Rutherford backscattering spectroscopy (RBS) measurements revealed that the α-Fe layer was nitrided to form the Fe_4N layer. In the magnetization versus magnetic field curves measured at room temperature, a two-step hysteresis loop was clearly observed, meaning that the two ferromagnetic layers were separated by the 2-nm-thick AIN barrier layer.