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Design of Nanoporous Ultra Low-Dielectric Constant Organosilicates by Self-Assembly



S Y. Yang, T L. Dull, J Sun, Albert F. Yee, P Mirau, C S. Pai, O Nalamasu, E Reichmanis, Eric K. Lin, V. J. Lee, D Gidley, W E. Frieze


Here we report a new class of materials that can reach ultra low- dielectric constants while maintaining good mechanical properties. In this approach, amphiphilic triblock copolymers, poly(ethylene oxide-b-propylene oxide-b-ethylene oxide) (PEO-b-PPO-b-PEO) are used as sacrificial templates in poly(methyl silsesquioxane) (MSQ), to generate nanopores. The structure and dynamics of triblock copolymers were studied by solid-state proton NMR. The domain size of polymer in MSQ is 2.2 nm with PPO at the interface between the MSQ matrices. When the composite was heated to above 400 degrees C, the MSQ matrix is cured, followed by the calcination of block polymers to generate pores. The porous materials have dielectric constants equal to or less than 2 and exhibit low I-V leakage, less than 10^lu-8^ A/cm2 at 0.5 MV/cm. Small angle neutron scattering (SANS) and positronium annihilation lifetime spectroscopy (PALS) revealed that these materials had extremely small pores, of the order of 2 nm to 3 nm.
Journal of the American Chemical Society


low-k dielectric, porous thin film, positronium annihilation lifetime spectr, self-assembly, small angle neutron scattering, x-ray reflectivity


Yang, S. , Dull, T. , Sun, J. , Yee, A. , Mirau, P. , Pai, C. , Nalamasu, O. , Reichmanis, E. , Lin, E. , Lee, V. , Gidley, D. and Frieze, W. (2001), Design of Nanoporous Ultra Low-Dielectric Constant Organosilicates by Self-Assembly, Journal of the American Chemical Society, [online], (Accessed May 29, 2024)


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Created March 31, 2001, Updated October 12, 2021