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Nanoporous Ultra Low-Dielectric Constant Organosilicates Templated by Triblock Copolymers



S Y. Yang, P A. Mirau, C S. Pai, O Nalamasu, E Reichmanis, J C. Pai, Yaw S. Obeng, J Seputro, Eric K. Lin, Hae-Jeong Lee, J Sun, D Gidley


Triblock polymers, poly(ethylene oxide-b-propylene oxide-b-ethylene oxide) (PEO-b-PPO-b-PEO), are used as molecular templates in poly(methyl silsesquioxane) (MSQ) matrices to fabricate nanoporous organosilicates. It is found that the fast solvent evaporation can avoid macroscopic aggregation of block copolymers in MSQ matrix. Solid-state NMR shows that in a spin-coated film the triblock copolymer microphase separates in the MSQ during a curing step and the polymer domain size is (3-15) nm, depending upon the polymer composition and loading percentage. When the films are heated to 500 oC, extremely small pores ((2-6) nm) are generated, which are studied by small angle neutron scattering (SANS) and positronium annihilation lifetime spectroscopy (PALS). These materials attain ultra low-dielectric constants (k 1.5) with strong electrical and mechanical properties.
Chemistry of Materials
14 No. 1


low-k dielectric, nanoporous thin film, organosilicate, positronium annihiliation lifetime spect, small angle neutron scattering, triblock copolymers, x-ray reflectivity


Yang, S. , Mirau, P. , Pai, C. , Nalamasu, O. , Reichmanis, E. , Pai, J. , Obeng, Y. , Seputro, J. , Lin, E. , Lee, H. , Sun, J. and Gidley, D. (2002), Nanoporous Ultra Low-Dielectric Constant Organosilicates Templated by Triblock Copolymers, Chemistry of Materials, [online], (Accessed June 22, 2024)


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Created December 31, 2001, Updated October 12, 2021