The stability of thin diblock copolymer films with respect to the annealing above the microphase separation temperature is investigated on long time scales and at different film thicknesses. Poly(styrene-block-p-methylstyrene) diblock copolymer films on top of silicon substrates are examined with scanning force microscopy and off-specular X-ray scattering. At film thickness below the lamellar spacing of the bulk material a dewetting is observed. The kinetics of the film destabilization are explainable within a spinodal dewetting model. The observed dewetting structures belong to a wet dewetting. In the case of film thicknesses which enable the buildup of a few lamellae no sign of instability was detected.

The lateral structures of dried thin films of the ampholytic diblock copolymer poly((methacrylic acid)-block-((dimethylamino)ethyl methacrylate)) adsorbed from dilute aqueous solution onto silicon substrates were investigated by scanning force microscopy (SFM) and diffuse X-ray scattering. The adsorbed amount of polymer, as a function of pH, reveals a maximum near the isoelectric point (IEP) of the polyampholyte. Different lateral structures are determined for samples adsorbed at pH values above the maximum of the adsorbed amount, as compared to the ones adsorbed at pH values below this maximum. At a pH around the IEP, the polyampholyte precipitates and the layers are formed by adsorption of flocks with sizes in the micrometer range. Lateral structures measured by SFM are similarly detected by diffuse X-ray scattering. The later technique delivers a statistical description of the lateral surface structures averaged over a larger area. The structures investigated are related to the polyampholyte structure in solution and can be explained by the interplay of the electrostatic interactions of the two oppositely charged blocks of the polyampholyte and the charged surface, as well as by the dependencies of charge densities on pH.

Thin poly(styrene-block-p-methylstyrene) diblock copolymer films on top of silicon substrates were examined right after preparation and during the early 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 correlation between the substrate and the copolymer surface within a limited film thickness and molecular weight range right after preparation. The transferred part of the roughness spectrum of the substrate is probed and explained as a morphology of a frozen liquid with a surface bending rigidity. During 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.