Scm pit v2 tip

Before the AFM measurement, the silicon wafer was immersed in a Piranha solution (H₂SO₄: H₂O₂ = 3:1) for 10 min to remove organic contaminants, then rinsed with pure ethanol and ultrahigh purity water (resistivity greater than 18.25 MΩ cm, TOC less than 10 ppb, and bacteria less than 10 CFU/ml), and finally blew dry with high-purity nitrogen. According to the use of cleaned silicon wafers (Ra < 1 nm), the sensitivity deflection and spring constant of the tips were calibrated by the thermal tuning method, which was about 65.67 nm/V and 1.9440 N/m, respectively (Ferreira et al., 2018 (link)). YM, adhesion, surface morphology, and Ra of the DFMs, were obtained in contact mode measured on an AFM (Bruker, Multimode 8). For imaging details, the SCM-PIT-V2 tip (Bruker) with a tip radius of 25 nm was used with a scan rate of 0.8 Hz and a resolution of 512 × 512 pixels. To minimize the influence of surface curvature, a 5 µm area at the DFM fiber was selected to take the measurements, which represented at least 100 force-distance curves per fiber, and the DFM measurement at given conditions was counted in three different scan areas on a single DFM to ensure reproducibility (Norman et al., 2021 (link)). Adhesion forces and the YM values were extracted from the data using Nanoscope analysis 1.8 software.