Nano-mechanical mapping by atomic force microscopy has been developed as an useful application to measure mechanical properties of soft materials at nanometer scale. To date

the Hertzian theory was used for analyzing force-distance curves as the simplest model among several contact mechanics between elastic bodies. However

the preexisting methods based on this theory do not consider the adhesive interaction in principle

which cannot be neglected in the ambient condition. A new analytical method was introduced to estimate the elasticity and the adhesive energy simultaneously by means of the JKR theory

describing adhesive contact between elastic materials. Poly(dimethylsiloxane) (PDMS) and isobutylene-co-isoprene rubber (IIR) were analyzed to verify the applicable limit of the JKR analysis. For elastic samples such as PDMS

the force-deformation plots obtained experimentally were consistent with JKR theoretical curves. Meanwhile

for viscoelastic samples

especially for IIR

the experimental plots revealed large deviations from JKR curves depending on scanning velocity and maximum loading force. Some nano-rheological arguments were employed based on the difference between these specimens.