The behavior of pinned layers using a high-field transfer curve

Abstract

In order to study the magnetic behaviors of pinned layers under different conditions, we applied compressive mechanical stress to a device and measured the transfer curve changes using a high-field (10 kOe) quasi-static tester. This permitted us to determine the behaviors of the pinned layers and the free layer. The results of the transfer curve measurements led to a classification of these curves. The governing conditions for each category were also determined. A normal transfer curve occurs when "E/sub j/>E/sub u//spl Gt/E/sub k/(AP1) and E/sub k/(AP2)," where: AP1 is the pinned layer adjacent to the antiferromagnetic (AFM) layer; AP2 is the pinned layer adjacent to the spacer; E/sub u/ is the coupling energy constant between the antiferromagnetic layer and the AP1; E/sub j/ is the anti-parallel coupling energy constant between AP1 and AP2 through the Ru; and E/sub k/(AP1) and E/sub k/(AP2) are the induced uniaxial anisotropic energy constants in AP1 and AP2 due to magnetostriction resulting from stress applied giant magnetoresistive (GMR) sensor.