Figure 1

Mechanical Young’s modulus map of PDMS (polydimethylsiloxane) calibration standards from Bruker; Young’s modulus values are 3.5 and 2.5 MPa, respectively (a, b). Quantitative analysis of Young’s modulus using Gaussian fit on log-normally distributed histograms (c). Examples of force vs indentation curves for the samples showing the raw data and fitting by the Sneddon model (d).