Published online by Cambridge University Press: 01 February 2011
Ordering of Co nanoparticles (∼11 nm in diameter) into 2-D and 3-D arrays on Si/Si3N4 substrates in external magnetic field and without field is reported. Arrays of particles were studied by TEM, SEM and GISAXS. The GISAXS measurements were performed at the wavelengths 0.155 nm and 0.336 nm and the spectra were simulated using distorted wave Born approximation approach. From results it follows that 2-D ordered monolayers of particles are composed of hexagonal close-packed mosaic blocks. 3-D arrays – rods are formed along magnetic field direction, being parallel or perpendicular to the substrate surface, when the colloid was more concentrated. Distribution of particles in rods was analyzed only by GISAXS and it was described by close packing of hard spheres. Their effective diameter was 14.7 nm.