Experimental characterization of adhesion between micro-size polymer particles and silicon substrates

Understanding the adhesion between a micro/nano-size particle and a substrate is of both scientific and technological interest. Recently we developed a rolling resistance moment based particle adhesion characterization technique. The particle-substrate adhesion was deduced from the response of the adhered particle to a lateral pushing force. With a custom-made nanomanipulator, lateral pushing tests on microsize polymer spheres were performed in the vacuum chamber of a scanning electron microscope and also in the ambient environment. An increasing lateral force was applied to the micro-particle, and the displacement of the particle in response to the lateral force was recorded. From the force-displacement relationship, the work of adhesion between the particle and the substrate was obtained. Experimental results were compared with the available data, and good agreement between the theoretical predictions and the experimental values was found.