Self-healing on OPA self-assembled monolayers

Controlled scratches on octadecylphosphonic acid self-assembled monolayers were made using atomic force microscopy tips as indenters. Scratch morpholo gical evolution was followed as a function of time, at room temperature, fo r samples prepared by drip coating and crystal melting methods. Self-healin g, ranging from partial to complete, was observed on drip coated samples. H owever, no substantial healing was observed on crystal melted samples. Such different behaviour is discussed in terms of the scratching mechanism on b oth sample types.