Thin poly(styrene-block-p-methylstyrene) diblock copolymer films on top of
silicon substrates were examined right after preparation and during the ear
ly stages of annealing. Using specular and off-specular X-ray scattering as
well as scanning force microscopy, the film morphology is determined. With
the spin-coating technique films are prepared which exhibit a roughness co
rrelation between the substrate and the copolymer surface within a limited
film thickness and molecular weight range right after preparation. The tran
sferred part of the roughness spectrum of the substrate is probed and expla
ined as a morphology of a frozen liquid with a surface bending rigidity. Du
ring annealing the energetically unfavorable roughness replication decays,
and an internal ordering is formed. The decay of long-range correlation is
explained by a surface diffusion where diffusion is slowed down as compared
to bulk behavior.