The Pore Structure and Its Impacts on Property and Performance of a Spin-on Porous Low k Dielectric
Yiping Liu, Wen-Li Wu, B J. Foran, D Gidley, Hae-Jeong Lee, Barry J. Bauer, B D. Vogt
A methylsilsesquioxane based porous spin-on dielectric has been evaluated at International SEMETCH (ISMT) for advanced interconnect applications. The pore structures have been have been characterized with various techniques including transmission electron microscopy (TEM), positron annihilation lifetime spectroscopy (PALS), small-angle neutron scattering (SANS) and specular X-ray reflectivity (SXR). The properties and CMP performance of the dielectric films have been also studied. The periodic tubular pore structures observed in the films played an important role in improving overall mechanical property. However, this type of film failed in CMP process via cohesive fracture, the layered structure near boundaries is the main culprit for the failures. The film might have improved cohesive strength withstanding the CMP process if one can make the pore structure more randomly orientated throughout the entire film thickness. Minimizing pore dimensions could be an effective way to avoid layered structures and improve mechanical strength of the porous low k films.
Advanced Metalization Conference
, Wu, W.
, Foran, B.
, Gidley, D.
, Lee, H.
, Bauer, B.
and Vogt, B.
The Pore Structure and Its Impacts on Property and Performance of a Spin-on Porous Low k Dielectric, Advanced Metalization Conference
(Accessed June 4, 2023)