Electromigration of magnetic thin films for predicting electrical-failured lifetime of GMR read heads

摘要

The electrical short after electrical open is thought to be due to the Cu atoms inter-diffusion to the top and bottom NiFe layers caused by the high temperature (or electrical burning) at high current density ambient in Cu interlayer. Typical electromigration failures such as voids (cracks) and hillocks were clearly observed at the center and cathode region of electromigration test stripes. The increase of resistance due to void formation and increase of shunting current or inter-diffusion paths due to hillock formation are considered to be serious potential problems in the degradation of the electrical reliability of GMR spin valve heads.