Degradation of magnetic tunneling junctions caused by pinhole formation and growth

A theory is developed to describe the pinhole formation and growth in magnetic tunneling junctions (MTJs) using the Kolmogorov–Avrami (KA) model. The theory relates the pinhole dynamics and the gradual degradation of the imperfect barrier layers and then the magnetic junctions under external stress. Form this study, analytical expressions of junction resistance and magnetoresistive (MR) ratio as functions of time are provided to characterize the junction degradation.