title: Mapping the elastic properties of granular Au films by contact resonance atomic force microscopy.
abstract: Endowed with nanoscale spatial resolution, contact resonance atomic force microscopy (CR-AFM) provides extremely localized elastic property measurements. We advance here the applicability of CR-AFM on surfaces with nanosize features by considering the topography contribution to the CR-AFM signal. On nanosize granular Au films, the elastic modulus at the grain scale has been mapped out by considering a self-consistent deconvolution of the contact geometry effect in the CR-AFM image. Significant variation in the contact area over granular topography arises as the probe is either in single- or multiple-asperity contact with the surface. Consequently, in extracting the elastic modulus from CR-AFM measurements on granular surfaces we considered both the normal and lateral couplings established through multiple-asperity contacts between the tip and the surface. Thus, by appropriately considering the change in the contact mechanics during CR-AFM imaging, variations in the elastic modulus have been revealed in the intergrain regions as well as across individual grains.
authors.affiliation: Ceramics Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
authors.forename: G
authors.initials: G
authors.lastname: Stan
authors.forename: R F
authors.initials: RF
authors.lastname: Cook