Homopolymer Penetration on Crosslinked Copolymer Mat

Ultra-thin films of benzocyclobutene (BCB)-functionalized random copolymers of styrene and methyl methacrylate were thermally-crosslinked on a substrate, but applicable to other systems, with a controlled thickness. Contact angles measured in nano scale describe that over the critical minimum thickness (~ 5.5nm) interfacial interaction of crosslinked random copolymer is well balanced. Neutron Reflectivity has been used to investigate in terms of the penetration of the polymer into crosslinked random copolymer P(S-r-BCB-r-MMA). Thus, to evaluate the critical minimum thickness which is at least required to control over the microdomain orientation of the PS- PMMA block copolymer systematically, deuterated PMMA was spin coated on crosslinked random copolymer controlled with various thickness from 1 to 10 nm. The neutron scattering length densities (SLD) of crosslinked random copolymer are increased with decreasing thickness, which means that the SLD contribution of d-PMMA to BCB layer is getting bigger because thin BCB layer is not enough to cover the SiOx.