Optimization of magnetic properties of electrodeposited CoP multilayers for sensor applications

摘要

In this study, we report a method to optimize the coercivity keeping the magnetostriction value constant in electrodeposited CoP multilayers for their applications in magnetoelastic magnetic sensors. We have deposited multilayers of two different compositions of CoP (Co_(0.74)P_(0.26) and Co_(0.83)P_(.17)) and studied the influence of the thickness of the different layers, keeping the total thickness constant. The results show a saturation magnetostriction in between the values of the magnetostriction of the two materials and independent of the thickness of the layers. However, the reduction of the thickness of the layers is accompanied with a clear reduction of the coercive field to values as low as 0.5 Oe and with a large increase of the permeability. This result shows, in the same material, an appreciable value of magnetostriction combined with low coercivity. Additionally we have found a controllable influence of the hydrogen flow on the direction of anisotropy which, in combination with other results, allows us to customize the material for its application in magnetic sensors.