Sensitive New Method for the Determination of Adhesion Force Between a Particle and a Substrate

Abstract

We have used an AT-cut quartz resonator with metal electrodes as the substrate. The material properties of the quartz are well characterized, and the resonate frequency can be determined accurately (l part in 10⁸ or better). When a particle was placed on the electrode, the resonant frequency increased, contrary to mass loading theory. If the particleresonator system is modeled mechanically as a coupled oscillator system, indeed the resonant frequency should increase. The increase is determined by the bonding force constant between particle and substrate, which we calculate. Experimental data on the autohesion force constants of Au spheres on etched Au electrodes in air are presented. Also, a brief description of non-linear modeling of the system is given.