Measurement system for adhesion force on single particles with microelectromechanical-based actuated tweezers

Abstract

A system for measuring the adhesion force of a single particle using microelectromechanical-system-based actuated tweezers (nanotweezers) and an atomic force microscope (AFM) cantilever was developed. In the proposed technique, a particle picked up with nanotweezers is brought into contact with and separated from the cantilever. The adhesion force is determined by measuring the deflection of the cantilever at the instant of separation from the particle. The throughput of measurement is much improved compared with that of a colloid probe AFM because the particle is picked up and held only by gripping with the nanotweezers, rather than sample preparation by manual cantilever mounting. A measurement apparatus was designed to realize the proposed system, and a force-displacement curve was successfully obtained. In addition, decreases in the adhesion force due to external coating added to particles were measured using the prototype apparatus.