Technique employing gold nanospheres to study defect evolution in thin films

A technique is described in which commercially available colloidal gold solution is used to deposit monodisperse gold nanospheres with diameters ranging from 20 to 60 nm directly onto silicon wafers. The technique for depositing the gold nanospheres is straightforward and requires Little in terms of infastructure or resources, The wafers containing gold nanospheres are first characterized by techniques such as atomic force,microscopy and transmission electron microscopy, after which they are coated with a thin film and recharacterized. This enables one to quantitatively study the evolution of thin-film defects nucleated by small substrate particles. An example is provided where the technique is used to study the,evolution of defects in Mo/Si multilayer films, which is of significant importance in the development of reticles for extreme ultraviolet lithography. (C) 2001 American Vacuum Society.