Quantitative mechanical characterization of materials at the nanoscale through direct measurement of time-resolved tip–sample interaction forces

Abstract

We introduce a new method for material characterization at the nanoscale using a recently developed atomic force microscope (AFM) probe. The FIRAT (force sensing integrated readout and active tip) probe is integrated into a commercial AFM system to obtain time-resolved interaction forces (TRIFs) between the probe tip and sample at speeds suitable for nondestructive and fast imaging of material properties. We present a basic interaction model to extract the material elasticity and surface energy. Numerical simulations are performed and compared to the experimental results for three different polymers and a silicon sample. We find that our interaction model does not completely explain the observed long-range surface forces, but it agrees fairly well with the measurements during the tip-sample contact.