Improving the quality factor of cantilevers in viscous fluids by the adaptation of their interface

Abstract

The adaptation of the fluid-microresonator interface enables the operation of cantilevers with high quality factor in viscous fluids. Partial wetting was proposed to implement the adapted interface by meniscus formation. An excellent quality factor of 79 was achieved in water applying the concept of partial wetting to thin film silicon nitride cantilevers. Compared to the quality factor calculated from Sader’s theory of the hydrodynamic damping of fully immersed cantilevers, this is an improvement by more than one decade. As a first application the partially wetted cantilevers were employed as mass sensors in water revealing a sensitivity of 2.77 fg/Hz.