Abstract
In this paper we discuss the van der Waals forces in atomic force microscopy when operating in liquids. We show that these forces are almost cancelled out for spherical tips immersed in liquids and seem to be in agreement with recent in situ electrochemistry results. Experiments as well as an analogy with Archimedes’s principle are proposed. Furthermore, we present experiments showing such spherical tips of hundred nanometers which can be fabricated in a reproducible manner and are stable.