Low temperature multimode atomic force microscopy using an active MEMS cantilever

Abstract

High resolution atomic force microscopy is routinely performed at ultra-high vacuum and at low temperatures by employing a qPlus tuning fork sensor. Due to its intrinsic self-sensing capability, very high dynamic stiffness, and large Q factor, qPlus sensors are pre-dominantly used for obtaining atomic resolution. In this work, we present a proof of concept for an active microelectromechanical system (MEMS) microcantilever with integrated piezoelectric sensing and demonstrate its capability to obtain scanning tunneling microscopy as well as high-resolution non-contact atomic force microscopy images on an atomically flat Au(111) surface. Equipped with a focused ion beam deposited tungsten tip, the active MEMS cantilever is able to obtain high contrast scanning tunneling and frequency shift images at the fundamental and at a higher eigenmode of the cantilever.