Laser processing of polymer nanocomposite thin films

Abstract

Current biotechnology and sensor research has enhanced the drive to establish viable methods for depositing high-quality polymer thin films. In this research, thin films of poly(methyl methacrylate) (PMMA) were prepared by matrix-assisted pulsed-laser evaporation (MAPLE). Up to 2wt% of carbon nanotubes were subsequently added to MAPLE target systems for deposition of polymer nanocomposite films. Targets were ablated using a 248nm (KrF) laser at fluences ranging from 0.045to0.75J∕cm2. In addition, polymer concentration in MAPLE targets was varied between 1 and 5wt% relative to the matrix solvent, in this case toluene. Films were deposited on Si substrates at room temperature in an Ar atmosphere. Molecular-dynamics simulations of MAPLE were utilized for interpretation of experimental observations. Particularly, the ejection of large clusters consisting of both PMMA and toluene molecules was studied and related to the observed morphology of the deposited films.