Thermal annealing of thin films

Hahm et al have analyzed different types of defects and their evolution with thermal annealing of thin films of PS-b-PMMA. One block copolymer was formed by 74wt.% of PS, so that the bulk morphology consisted of hex-agonaUy packed PMMA cylinders in a PS matrix. Films of 50 mn thickness were cast onto silicon nitride supports and annealed at different temperatures and for different times under inert atmosphere. The film morphology was formed by a PMMA layer wetting the substrate and one single layer of PMMA cylinders oriented parallel to the substrate. 

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