Figure 1

Device structure and TMR and TMC under no bias voltage. (a) Schematic of an MgO-based MTJ, with the structure: SiO₂/Ta(5 nm)/Co₅₀Fe₅₀(2 nm)/IrMn(15 nm)/Co₅₀Fe₅₀(2 nm)/Ru(0.8 nm)/Co₄₀Fe₄₀B₂₀(3 nm)/MgO(2 nm)/Co₄₀Fe₄₀B₂₀(3 nm)/contact layer. The measurement set-up for TMC and TMR is also shown. The magnetic field is applied along the magnetic easy-axis direction of Co₄₀Fe₄₀B₂₀ layers. (b) TMR and (c) TMC curves of an MgO-based MTJ. The frequency is 60 Hz and the DC voltage is 0 V. Frequency dependence of (d) TMC and TMR and (e) the capacitance C_P(AP)in the P(AP) configuration. The solid plots represent the experimental data and the solid lines represent the calculation results obtained by Debye-Fröhlich model, described by Eq. (2).