Structural characterization of periodic arrays of magnetic dots

We have investigated the structure and regularity of macroscopically large arrays of submicron magnetic Au/Co/Au dots, which were prepared by combinin g electron beam lithography, molecular beam epitaxy, and lift-off technique s. Atomic force microscopy was used to characterize the surface roughness o f the dots and to show the reproducibility of dot size and periodicity over large areas; low-angle x-ray diffuse scattering experiments were employed to construct a mapping of the reciprocal space in the vicinity of the (000) reflection of the dots. The reciprocal space mapping thus provides informa tion about the internal structure of the dots, as well as about the lateral periodicity of the dot array. This work underlines the important complemen tarity of scanning probe and x-ray diffraction techniques for the detailed characterization of patterned structures. We observed that the x-ray diffra ction patterns are extremely sensitive to the orientation of the dot lattic e with respect to the incoming x-ray beam, allowing a quantitative analysis of the lateral periodicity of the dot array and the size of the individual dots. (C) 2000 American Institute of Physics. [S0021- 8979(00)05309-3].