Post-etch template removal strategy for reduction of plasma induced damage in spin-on OSG low-k dielectrics

Abstract

In this study we demonstrate an approach for reduction of plasma induced damage in spin-on organosilica low-k dielectric films. These films are deposited from sols containing amphiphilic surfactant molecules as sacrificial phase. Both bulk material hydrophilization and surface roughening caused by etching plasma were significantly lowered. This is related to controlled partial removal of templating organic molecules at the material preparation stage. Short UV-assisted curing with broadband UV-light source (λ > 200 nm) was found to be an efficient strategy for the template residue removal applied after completing the etching process. Three steps of the proposed approach, including initial material pre-formation, etching and cleaning of pore walls from template residue, are investigated on blanket films.