Observation of liquid neck formation with scanning force microscopy techniques

In the present work, we describe a technique to measure the tip-sample interaction in a scanning force microscope setup with high precision. Essentially, the force exerted on the cantilever is acquired simultaneously with a spectrum of the cantilever. This technique is applied to study the behavior of the microscope setup as the tip approaches a sample surface in ambient conditions. The measured interaction can only be understood assuming the formation of a liquid neck and the presence of a thin liquid film on the tip as well as on the sample.