The switch happens mid-scan On a battery electrode, the scan changes from contact ResiScope to Soft Interaction Control halfway through — Soft IC improves the measurement without scratching the surface. - No shear on the particle, no scratching - Structure inside the particle becomes readable - Resistance — 314 kΩ to 902 GΩ Soft IC mode Contact-mode control, resonant-mode gentleness In Soft Interaction Control the tip touches the surface once per point with a force set directly through the cantilever deflection, then lifts away before moving on. The force is known and identical at every point, and no lateral force is applied to the sample. - Direct force control: one parameter, the deflection; the force follows from Hooke’s law - No friction or shear: the tip is never dragged across the surface - Less damage, longer tip life: soft, sticky and loosely bound samples stay intact - Quantitative channels: topography, stiffness, adhesion and electrical signals from the same touch Soft ResiScope™ on VO₂ — topography and resistance, 10 µm Compared with contact mode - No lateral forces - Less sample damage - Longer tip lifetime Compared with resonant (tapping) mode - Force controlled directly, with a single parameter - Force calculated directly, not inferred from an amplitude - More straightforward operation PDMS, 90 µm, Soft IC — topography, adhesion and Young’s modulus (1.2 to 10 MPa); the same mode carries Soft ResiScope™, Soft SThM and Soft PFM. How it works Four steps at every point 1. Topography and stiffness — the tip approaches and touches the surface; height and contact stiffness are recorded. 2. Constant force — the same maximum force at every point makes the measurements quantitative. 3. Adhesion — on retraction, the pull-off force is measured. 4. Next point — the tip lifts clear of the surface and moves on without any lateral force. Electrical, piezoelectric and thermal measurements are made during the contact: Soft ResiScope™, C-AFM, PFM and SThM all run in Soft IC, and Soft MEKA turns the force curves into stiffness, adhesion and Young’s modulus maps. Soft IC in liquid Approach, scan, retract, next point. No lateral friction. What is Soft Interaction Control (Soft IC) in AFM? Soft Interaction Control is the intermittent-contact mode of the Nano-Observer AFMs. At every point the tip touches the surface with a force set directly through the cantilever deflection, then lifts away before moving to the next point. It combines the direct force control of contact mode with the absence of friction of resonant (tapping) mode. How is Soft IC different from tapping mode? In resonant (tapping) mode the force is controlled indirectly, through the oscillation amplitude. Soft IC controls it directly with one parameter, the deflection, so the force is known and the same at every point. That makes mechanical and electrical measurements quantitative while still avoiding lateral forces. Which measurements can be made in Soft IC? Topography, stiffness, adhesion and Young’s modulus (Soft MEKA), resistance and current (Soft ResiScope), conductive AFM, piezoresponse (Soft PFM) and thermal properties (Soft SThM). Which samples benefit from Soft IC? Soft, sticky, fragile or loosely attached samples that contact mode would damage or drag: polymers, organic electronics, battery electrodes, nanotubes and particles, and biological samples.
