Design and Fabrication of Spin Torque Transfer Devices with Magnetic Nano-Current-Confined Structures for Lower Switching Current Density

This paper investigates the design of a hybrid (composite) free layer in order to implement a new spin switching configuration to reduce the switching current. The hybrid free layer consists of one and two free layer and couples to a magnetic granular structured nano-current-confined (NCC) layer. The magnetic tunnel junction (MTJ) devices were patterned into 180 nmtimes250 nm ellipse shape by using phase-shift lithography. The current-induced magnetization switching of the MTJs with and without NCC structure was measured by four-point probe method. Results show that for MTJ with NCC structure, the critical switching current decreased dramatically .