Poly(dimethylsiloxane-b-methyl methacrylate): A Promising Candidate for Sub-10 nm Patterning

Luo, Y., Montarnal, D., Kim, S., Shi, W., Barteau, K. P., Pester, C. W., Hustad, P. D., Christianson, M. D., Fredrickson, G. H., Kramer, E. J., Hawker, C. J.
48 (11), pp 3422–3430

We report herein the modular synthesis and nanolithographic potential of poly(dimethylsiloxane-block-methyl methacrylate) (PDMS-b-PMMA) with self-assembled domains approaching sub-10 nm periods. A straightforward and modular coupling strategy, optimized for low molecular weight diblocks and using copper-catalyzed azide–alkyne “click” cycloaddition, was employed to obtain a library of PDMS-b-PMMA and poly(dimethylsiloxane-block-styrene) (PDMS-b-PS) diblock copolymers. Flory–Huggins interaction parameters, determined from small-angle X-ray scattering experiments, were high for PDMS-b-PMMA (χ ∼ 0.2 at 150 °C), suggesting this diblock copolymer system has promise for sub-10 nm lithographic applications when compared to the corresponding PDMS-b-PS diblock copolymers (χ ∼ 0.1 at 150 °C). Performance evaluation in thin film self-assembly experiments allowed domain periods as small as 12.1 nm to be obtained, which is among the smallest highly ordered nanoscale patterns reported hitherto for thermally annealed materials.