Webinar

Conductive atomic force microscopy (CAFM) uses conductive probes mounted upon a cantilever to measure the current between the probe and a surface with mechanical forces controlled via a feedback loop monitoring the cantilever deflection. CAFM enables both the topography, current maps and current vs voltage characteristics of samples to be measured at nanometre length scales, which yields details of the structure and functional properties of surfaces which cannot be revealed by other techniques. For example: electrical probe stations lack spatial resolution, electron microscopy techniques do not facilitate electrical characterisation and scanning tunnelling microscopy requires surfaces of uninterrupted conductivity. In this webinar, we will review the working principles of CAFM, discuss examples of state-of-the-art measurements and provide a live demonstration of a CAFM experiment.
After introducing the working principles of CAFM, we will explore its applications. We first demonstrate the use of CAFM in exploring the registry of layered materials heterostructures, specifically moiré patterns between single layer graphene and hexagonal boron nitride [1] and reconstructed domains in marginally twisted (0°) 2L-MoS2 [2,3]. After touching on the spatial resolution offered by CAFM, we then discuss its ability to measure localised current vs voltage characteristics in an automated fashion both over individual AB and BA stacked domains in marginally twisted (0°) 2L-MoS2. In the final part of the webinar, we introduce the use of high voltage CAFM to study the breakdown of dielectric layers [4,5] via a live demo and explore its use in extracting the local dielectric strength of materials and studying their breakdown mechanisms.