Current-driven magnetization switching in CoFeB/MgO/CoFeB magnetic tunnel junctions

The current-driven magnetization switching in CoFeB/MgO/CoFeB magnetic tunnel junctions (MTJs) with various free layer materials including synthetic structure was studied in this paper. The MTJ films were deposited on SiO
₂
/Si substrates using RF magnetron sputtering. The tunnel magnetoresistance (TMR) ratios and current-voltage (I-V) characteristics of the the MTJs were measured at room temperature using a dc four-probe method and with a magnetic field of up to 1 kOe. The TMR ratio and the current-driven magnetization switching at critical current densities were shown as a function of annealing temperature for two types of MTJs with different free layer.