Visualizing and measuring thin-film thickness at the nanoscale during dynamic evolution has been an open challenge for the long term. Here, a joint-imaging method and the thereof innovative procedure are presented for merging digital holography (DH) and white light colorimetric interferometry (WLCI) measurement data in a single intelligent tool.
The approach allows a complete quantitative study of the dynamic evolution of freestanding thin films under high spatial resolution and full-field modality over a large area. By merging interferometric and holographic fringes, it is possible to overcome the lack of digital holography in thickness measurements of ultrathin layers, providing a reliable reference for full-field quantitative mapping of the whole film with interferometric accuracy.
The digital holography and white light colorimetric interferometry tool opens a route for comprehending deeply the physics behind the behavior of freestanding thin liquid films as it provides an in situ, continuous monitoring of film formation and dynamic evolution without limits of thickness range and in full-field mode. This can be of fundamental importance to many fields of applications, such as fluids, polymers, biotechnology, bottom-up fabrication, etc.