Friction reduction of suspended multilayer h-BN based on electrostrain

Abstract

Hexagonal boron nitride(h-BN) is an excellent candidate for nano/micro-electromechanical systems (N/MEMS) as lubrication due to its outstanding mechanical and insulation properties. In this work, we reported the friction reduction of suspended multilayer h-BN under the bias voltage of the substrate using atomic force microscopy (AFM). The degree of electrostrain of the h-BN corresponds to the bias applied to the substrate. The electrostatic force between the suspended h-BN and the substrate increased electrostrain and decreased adhesion stress based on the quantitative analysis of pull-off and stick–slip curves under different biases. The electrostatic force between the suspended h-BN and the substrate dominants the increased electrostrain and the decreased adhesion stress based on the quantitative analysis of pull-off and stick–slip curves under different biases. The contribution of electrostrain to friction reduction of suspended h-BN is proposed by decreasing interfacial shear strength with increasing bias based on the calculation of the friction-load dependence. This study provides a new guideline for the reduced friction loss and increased lifetime of N/MEMS devices.