Investigation of ion beam deposited spin valve interface structure by Co-59 nuclear magnetic resonance

Co nuclear magnetic resonance was used to study the bulk and interface micr ostructure in the unpinned Co layer in a series of highly (111)-textured io n beam deposited spin valves. The intent of the study is to determine the d egree of Co interface intermixing and any possible variation of the Co laye r microstructure as a result of weakening (111) texture of the NiFe/Co/Cu/C o/NiFe/FeMn film stack. We found that the interfaces are diffused over simi lar to 2 monolayers on both sides of the Co layer, involving an equivalent of about 3 Angstrom of Co per interface and vary only slightly with deterio rating texture. The main structural change is the drop of perfect fcc stack ing in the Co layer. (C) 1999 American Institute of Physics. [S0021-8979(99 )48208-8].