NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
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.
X-Ray Reflectivity as a Metrology to Characterize Pore Size Distributions in Low-K Dielectric Films
Published
Author(s)
V. J. Lee, Christopher Soles, D W. Liu, Barry J. Bauer, Wen-Li Wu
Abstract
A methodology is described whereby we use specular x-ray reflectivity to characterize the pore size distributions in porous low-K dielectric films. X-ray reflectivity provides a sensitive measure of the density (and thus porosity) in a thin, low-K dielectric film. When these reflectivity experiments are done in the presence of toluene vapor, the phenomenon of capillary condensation can be used to extract the pore size distribution in the film. Condensation of the toluene inside a pore will effectively increase the average density of the film. From the Kelvin equation, we know that there is a critical radius at which the solvent vapor will spontaneously condense inside the pores, and this radius changes with the partial pressure. So by varying the partial pressure and monitoring the change in the film density, we can map out the pore size distributions in sub-micron thick low-K dielectric films.
Lee, V.
, Soles, C.
, Liu, D.
, Bauer, B.
and Wu, W.
(2002),
X-Ray Reflectivity as a Metrology to Characterize Pore Size Distributions in Low-K Dielectric Films, Polymer Preprints, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=852038
(Accessed October 1, 2025)