Numerical simulation of current density induced magnetic failure for giant magnetoresistance spin valve read sensors

Abstract

It was numerically demonstrated that current-in-plane (CIP) and current-perpendicular-to-plane (CPP) Ir20Mn80 based giant magnetoresistance spin valve read sensors operating at an extremely high current density (J≥1×108 A/cm2) show completely different electrical and magnetic failure mechanisms: (1) CIP read sensors, electromigration-induced Cu spacer diffusion and correspondingly degraded interlayer coupling were primarily responsible for the failures; while, (2) CPP read sensors, the deterioration of exchange bias due to thermomigration-induced Mn interdiffusion at the Co80Fe20 /Ir20Mn 80 interface was found to be dominant. The different temperature and current distribution resulting in different mass-transport mechanisms are the main physical reasons for the failure. © 2010 American Institute of Physics.