Magnetic combinatorial thin-film libraries

Magnetic combinatorial libraries have been fabricated to investigate complex magnetic thin-film systems and to provide test samples for the development of on-wafer metrologies. The use of combinatorial material techniques is a new and powerful method to develop and investigate magnetic thin-film systems that require ternary or quaternary alloys. Libraries were fabricated by co-depositing Ni_0.8Fe_0.2, Co, and Tb in a configuration designed to provide compositional gradients across the wafer. The initial libraries consist of 20×20 sites, each marked with an identification number. The composition varies across the wafer, with compositions of Tb_0.60(NiFe)_0.10Co_0.30, Tb_0.22(NiFe)_0.22Co_0.56, Tb_0.10 (NiFe)_0.65Co_0.25 at the Tb, Co, NiFe rich corners respectively. The purpose of this particular library was to investigate optimal magnetostrictive thin films that have large magnetostriction yet relatively small saturation fields, and to look for compositions that have large magneto-optical effects