Fabrication and magnetic properties of electron beam lithography patternedarrays of single crystalline Fe(001) squares

The fabrication method of arrays of iron squares separated by submicrometri c distances is presented, The magnetic elements are defined on a single cry stal Fe(001) film by electron beam lithography followed by a ion beam etchi ng process. The obtained Fe squares present smooth surfaces and homogeneous sizes over areas as large as 500 mum x 500 mum as analyzed by scanning ele ctron and atomic force microscopies, The lateral size of the squares have b een varied in the range 1-10 mum in order to analyze the size dependence, T he magnetic properties of the single crystalline squares have been studied by magnetooptical Kerr effect. The results reveal an important change in th e hysteresis loops as the square dimensions are reduced below a threshold o f 3 mum.