Self-assembled block polymer templates as high resolution lithographic masks

Diblock copolymer thin films have recently received more attention due to their ability to organize into nanometric structures under thermal annealing. This phenomenon was studied for an asymmetric poly(styrene-block-methyl methacrylate) (PS-b-PMMA) diblock copolymer with PMMA weight fraction of 0.3 and MW = 67,100 g mol−1. First, the surface chemistry of the substrate was modified to favor the formation of vertical PMMA cylinders surrounded by a PS matrix. We have also found that the mean pore area of cylinders increases with their coordination number. Finally, these films were used as a deposition or etching mask to produce well-organized arrays of holes, dots and nanopillars.