Characterization of Nanoporous Ultra Low-k Thin Films Templated by Copolymers with Different Architectures

Triblock, diblock and random copolymers of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) are used as molecular templates in poly(methyl silsesquioxane) (MSQ) matrices to fabricate ultra low-k dielectric materials (k less than 2.0). Solid-state NMR shows that polymer architecture plays an important role in the polymer domain size and the polymer-matrix interface in the nanocomposites. 

Positronium annihilation lifetime spectroscopy (PALS) reveals that porous MSQ film templated by triblock copolymers ( in the range of ~ 5000 to 12000 g/mol) have smallest pores and highest percolation threshold compared to those templated by diblock and random copolymers.