Structural characterization of methylsilsesquioxane-based porous low-k thin films using X-ray porosimetry

Methylsilsesquioxane based porous low-k dielectric films with different porogen loading have been characterized using X-ray porosimetry to determine their pore size distribution, average density, wall density and porosity. By varying the porogen content from 1 % to 30 %, the porosity and the average pore size changed from 12 % to 34 % and from 10 /spl Aring/ to 15 /spl Aring/ in radius, respectively. The wall density was found to be independent of the porogen content and it appeared that the porogen is not 100% effective in generating pores. Pore size of these samples was also obtained from small angle neutron scattering measurements and the results were found to be consistent with that from XRP.