Correcting defects in area selective molecular layer deposition

Abstract

Area selective deposition, as used with atomic layer deposition and molecular layer deposition (MLD), is a rapidly emerging field of study due to its potential applications in micro- and nanoelectronic devices. Previous studies have shown successful area selective MLD of nanoscale organic thin films using self-assembled monolayers (SAMs) as blocking layers. In this report, the authors expand upon the use of SAMs by implementing an etching process for the removal of the SAM resist once the MLD film has been deposited. This process has the benefit of removing unwanted deposits, which improves MLD selectivity on a dielectric by 380-fold over using a SAM layer alone and enables twice the amount of polymer film to be selectively deposited compared to that in previous reports. Although the etching leaves intact the polymer film in unblocked regions, the clean removal of the polymer film is limited at pattern interfaces. This effect is attributed to intermolecular interactions, such as polymer entanglement and hydrogen bonding between the chains.