Force modulation imaging is an atomic force microscopy (AFM) technique that identifies and maps differences in surface stiffness or elasticity1. It is one of several techniques developed as extensions of AFM. These techniques probe various surface properties to differentiate between the different materials that make up heterogeneous surfaces. Force modulation imaging has many applications, including locating transitions between different components in composites, rubber, and polymer blends; imaging organic materials on hard substrates; detecting residual photoresist on integrated circuits; and identifying contaminants on various surfaces.