IrMn spin valves using Si layers

Abstract

Effect of Ir-Mn composition on exchange bias and thermal stability of spin valves with nano-oxide layers Enhancement of exchange bias in Mn-Ir/Co-Fe based spin valves with an ultrathin Cu underlayer and in situ Mn-Ir surface modification Thin silicon layers can be used to good effect in spin valve sensors. Si underlayers increase the ⌬R/R from 7.1% to 8.8% in top spin valves, and 6% to 7.8% for bottom spin valves. This is accompanied by a decrease in sheet resistance and the exchange anisotropy field. These results suggest that films grown on Si have larger grains than those with Ru seed layers. Si atoms are efficient as scattering sites, reducing ⌬R/R and increasing the sheet resistance when placed in active layers. This can be used to improve the properties of antiparallel-pinned spin valves.