Electrical study of NiFe/Al2O3/Si tunnel diodes for magnetic memories

This work is focused on the electrical characterization of NiFe/Al
₂
O
₃
/Si tunnel diodes that can be used for spin injection into silicon. The effect of annealing on the electrical properties of the diodes has been studied by the analysis of the capacitance-voltage characteristics. This analysis shows that the Al
₂
O
₃
densification annealing can largely decrease the Al
₂
O
₃
/Si interface state density bringing it to the state of the art values. Current-Voltage analysis shows a direct tunneling mechanism of transport through 2 nm alumina barrier. This result shows that Al
₂
O
₃
has all the prerequisites to be used as a tunnel barrier for coherent spin injection into silicon.