Bilayer plasma polymer (PP) films were examined using a combination of X-ray and neutron reflectometery and X-ray photoelectron spectroscopy to gain an understanding of the interfacial structures that form between the films. Three different PP films were produced from the monomers hexamethyldisiloxane (HMDSO), di(ethylene glycol) dimethyl ether (DG), and allylamine (AA) at different load powers. These films were used as "substrates" for the subsequent deposition of a deuterated DG (dDG) PP top film. The width of the interfacial region was found to be strongly dependent on the chemical and physical properties of the substrate film. These findings have relevance to the general use and application of plasma polymer films. We examine the effect of load power and monomer chemistry on the interface that forms between a plasma polymer substrate and a deuterated plasma polymer top film.
- neutron reflectometry
- plasma polymerization