Figure 2
Overview of the indentation curve processing and area function calibration procedure. Inset: scheme of tip-surface interaction during indentation at maximum load. (a) Typical indentation measurement with loading (blue) and unloading curves (red). The hatched areas A0, A1 and A2, are used for characterization of adhesion and viscoplasticity respectively. (b) Contact area function for both DT and PPP probes as a function of indentation depth hc using AFC method (data points-black symbols- and fits-black lines) and adjusted spherical-conical models (blue lines, Supplementary Section S1). Insets: Electronic microscopy of DT (scale bar = 400 nm) and PPP tips (scale bar = 100 nm).
