HIGH-CURRENT DENSITY-MEASUREMENTS OF GIANT MAGNETORESISTIVE SPIN-VALVES FOR MAGNETIC RECORDING AND SENSOR APPLICATIONS

High current density measurements on giant magnetoresistive NiFe-Cu-Ni Fe-FeMn spin-valve devices are presented. The spin-valve magnetoresist ive response, Delta R/R, is highly temperature dependent; at temperatu res near the blocking temperature there is a considerable reduction of pinning field and decrease in device response. It is desirable to mea sure certain high current density effects such as electromigration and self-field effects separately from the effects of ohmic heating. For this purpose, we introduce pulsed current techniques necessary to redu ce ohmic heating in wafer-level device measurements and we deduce a re quired pulse width of 15 ns to minimize device heating.