Thermally induced self-assembly of cylindrical nanodomains in low molecular weight PS-b-PMMA thin films

The phase behaviour in thin films of an asymmetric polystyrene-b-polymethylmethacrylate (PS-b-PMMA) block copolymer with a molecular weight of 39 kg mol 1 was assessed at a wide range of temperatures and times. Cylindrical PMMA structures featuring a diameter close to 10 nm and perpendicularly oriented with respect to the substrate were obtained at 180 degrees C in relatively short annealing times (t <= 30 min) by means of a simple thermal treatment performed in a standard rapid thermal processing machine.