In situ visualization of LbL-assembled film nanoscale morphology using scanning ion conductance microscopy

Abstract

The layer-by-layer (LbL) technique is a simple method employed to fabricate multi-layered thin films by alternately adsorbing anionic and cationic polyelectrolytes through the electrostatic interactions. In order to fabricate thin films with desirable structures and properties, it is crucial to understand how different fabricate conditions direct the thin film formation. In this study, we performed the In situ characterization of thin firm using scanning ion conductance microscopy (SICM), where the thickness as well as the surface roughness are evaluated for films with different layer numbers. Moreover, the effects of the pH and ionic strength on the fabrication of the thin films were investigated. SICM enabled the determination of the film thickness with a single layer level and the comprehension of the relationship between the surface morphology and fabrication conditions.