Study on Magnetic Domain Structure of Co/Pt Dots Array

Co/Pt multilayer dots arrays with 580-nm periodicity were fabricated using Laser interference lithography (LIL) and an ion-beam milling technique. We obtained uniform dots arrays with a large area by optimizing the exposure parameters and improving exposure conditions. We obtained their shapes and magnetic domain structures and investigated using an Atomic force microscope (AFM) and Magnetic force microscope (MFM). The AFM and MFM images show:1) when their size is smaller than 400nm, the dots are in single-domain state and their shape tends to be circular; and 2) when their size is greater than 400nm, the dots are in multi-domain state and they tend to form squares. The dots arrays possibly can be used in nano-scale magnetic storage.