Xikun Hu, Wenlin Liu, et al.
IEEE J-STARS
We present a supercritical CO2 (SCCO2) process for the preparation of nanoporous organosilicate thin films for ultralow dielectric constant materials. The porous structure was generated by SCCO2 extraction of a sacrificial poly(propylene glycol) (PPG from a nanohybrid film, where the nanoscopic domains of PPG porogen are entrapped within the crosslinked poly(methylsilsesquioxane) (PMSSQ) matrix. As a comparison, porous structures generated by both the usual thermal decomposition (at approximately 450 °C) and by a SCCO 2 process for 25 and 55 wt% porogen loadings were evaluated. It is found that the SCCO2 process is effective in removing the porogen phase at relatively low temperatures (<200 ° C) through diffusion of the supercritical fluid into the phase-separated nanohybrids and selective extraction of the porogen phase. Pore morphologies generated from the two methods are compared from representative three-dimensional (3D) images built from small-angle x-ray scattering (SAXS) data. © 2004 Materials Research Society.
Xikun Hu, Wenlin Liu, et al.
IEEE J-STARS
S.F. Fan, W.B. Yun, et al.
Proceedings of SPIE 1989
Kenneth R. Carter, Robert D. Miller, et al.
Macromolecules
I. Morgenstern, K.A. Müller, et al.
Physica B: Physics of Condensed Matter