Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Nanopore Formation in a Polyphenylene Low-k Dielectric



M S. Silverstein, Michael Shach-Caplan, Barry J. Bauer, R C. Hedden, V. J. Lee, B G. Landes


Nanometer-scale porosity is being introduced into low-k dielectrics in an attempt to achieve interlevel metal insulators with permittivities of less than 2.0. It has proven extremely difficult to describe pore formation and to characterize the porous structure. This research investigates pore formation in a polyphenylene low-k dielectric based on pyrolysis of a porogen (26 % by volume) in a polyphenylene matrix. One unique aspect of this research is the description of the nanoscale structure at various stages of pore formation through the use of a deuterated porogen. The combination of x-ray reflectivity (XRR) and small angle neutron scattering (SANS) was found to be a powerful technique for describing porogen degradation and pore formation in nanoporous materials.The average radius of the porogen domains was about 60 and the size distribution was relatively broad. The smaller porogen domains collapse during degradation, while the larger domains become stable pores. The collapse of the smaller domains yields a significant reduction in film thickness, a porosity that is significantly smaller than the porogen content, a relatively narrow pore size distribution and an average pore size of about 80 .
No. 10


low-k, nanoporous, polyphenylene, porogen, SANS, XRR


Silverstein, M. , Shach-Caplan, M. , Bauer, B. , Hedden, R. , Lee, V. and Landes, B. (2005), Nanopore Formation in a Polyphenylene Low-k Dielectric, Macromolecules, [online], (Accessed April 21, 2024)
Created April 1, 2005, Updated February 17, 2017