Webinars

This webinar will explore the advanced characterization of van der Waals (vdW) heterostructures, focusing on the optical and electronic properties of trapped bubbles within these materials. We will demonstrate how the integration of Imaging Spectroscopic Ellipsometry (ISE) and Atomic Force Microscopy (AFM) can provide a deeper understanding of complex surface systems. Using a twisted bilayer graphene (TBG) on hexagonal boron nitride (hBN) sample, we will illustrate how ISE effectively measures layer thicknesses and optical properties, while AFM offers insights into surface topography and the Moiré superlattice structure.

The webinar will highlight the impact of microscopic trapped bubbles, formed during the fabrication process, on the optical properties of vdW heterostructures. These bubbles, acting as local optical cavities, alter the refractive index, extinction coefficient, and absorbance of the TBG layer, which is crucial for applications in optoelectronics and photonics. Attendees will learn how combining ISE and AFM not only enhances the accuracy of measurements but also enables a comprehensive analysis of both surface and sub-surface properties. This synergy between ISE and AFM will be presented as a powerful tool for advancing the characterization of 2D materials and exploring their potential in next-generation technologies.