AFM cantilever structure revisited – improving AFM imaging speed through unconventional cantilever design

G.E. Fantner, N. Hosseini, M. Neuenschwander, P. Swain, M. Penedo
EPFL,
Switzerland

Keywords: AFM cantilevers, self sensing, HS-AFM

Summary:

Cantilevers are at the heart of the measurement in atomic force microscopy, yet their basic shape and material have barely changed since the inception of AFM. In this presentation I will discuss avenues through which AFM cantilevers can be adapted to better meet the requirements for next generation AFM applications. This includes high-speed AFM in liquids, high-speed AFM in air, self-sensing and self-actuating AFM as well as correlated AFM/SEM/FIB imaging. Traditionally, AFM cantilevers are made of typical microfabrication materials such as silicon or silicon nitride. While these materials are very well suited for microfabrication, they have similar mechanical properties and therefore restrict the available design space. Microfabrication compatible polymers, however, have storage- and loss-moduli orders of magnitude different than silicon and silicon nitride. Incorporating such polymers into the fabrication process of AFM cantilevers allows us to tune the static and dynamic properties of the cantilevers and optimize them for the respective applications. I will present our recently developed tri-layer microfabrication technology which incorporates semiconductor materials, ceramics, and polymers into one microfabrication process. The resulting cantilevers are faster, have integrated sensing and actuation electronics, are inherently fluid compatible, and can be coated with additional layers for AFM modes such as KPFM and MFM.