Low k, Porous Methyl Silsesquioxane and Spin-On-Glass

Abbe T. Kohl
1999 Electrochemical and solid-state letters  
Low dielectric constant, porous silica was made from commercially available methyl silsesquioxane (MSQ) by the addition of a sacrificial polymer, substituted norbornene polymer containing triethoxysilyl groups (NB), to the MSQ. The silsesquioxane-NB polymer film mixture was thermally cured followed by decomposition of the NB at temperatures above 400°C. The dielectric constant of the MSQ was lowered from 2.7 to 2.3 by creating 70 nm pores in the MSQ. The voids created in the MSQ exhibited a
more » ... ed-pore structure. The concentration of NB in the MSQ affected the number of pores but not their size. Porous films were also created in a methyl siloxane spin-on-glass and its dielectric constant was lowered from 3.1 to 2.7. Infrared spectroscopy was used to follow the curing of the MSQ and decomposition of the NB.
doi:10.1149/1.1390740 fatcat:gbnkgdt4irgzjltcxiuxbax3eu