Effect of film morphology on grain boundary segregation induced magnetic properties in heat treated CoCrPt/Cr films

Effect of Co grain morphology on Cr segregation induced magnetic properties was investigated in heat treated CoCrPt/Cr thin films. In this work, interdiffusion and Cr segregation induced Co grain isolation were studied by post-deposition annealing of the CoCrPt films deposited on a Cr underlayer at different sputtering conditions. The films with voided boundaries showed a stronger heating temperature dependence of magnetic properties than the dense films, due to the promoted Cr segregation at the boundaries. TEM observation indicated that Cr was segregated from the Cr underlayer to the void boundaries of the CoCrPt films. The grain morphology of as-deposited films played an important role in Cr segregation during heat treatment, and the intergranular exchange decoupling was enhanced by the diffusion of Cr atoms into the voids isolating the Co grains.