Chemisorption-induced microcantilever deflection: a theoretical model

Abstract

Microcantilever-based techniques are often used to measure the changes of surface stress and infinitesimal mass induced by adsorbed atoms/molecules on the cantilever surface. In this paper, an energy method using a valence force model is presented to study the cantilever bending behaviour induced by chemisorption. The surface stress change induced by chemisorption is estimated. The chemisorption of oxygen on Si(100) surface is taken as a representative example. The results are consistent with relevant experimental observations. It is shown that chemisorption-induced deformation behaviour of cantilevers shows a distinct dependence on the bond configurations formed by adsorbed atoms and substrate atoms, as illustrated by the Si(100)-O cluster in this paper. The study is helpful for the optimal design of microcantileverbased measurement techniques.