Published online by Cambridge University Press: 28 February 2011
A sol-gel method was used to prepare bulk, closed pore, amorphous alumina-silica. Films prepared from this 47wt% A12O3-SiO2 composition were examined by SAW, ellipsometry and electrical measurements. The films were found to have a surface area of 1.1 cm2/cm2, a refractive index of 1.44 at 633 nm, and a relative permittivity of 6.2 at 200 KHz. These properties indicate potential applications as hermetic seals, barrier coatings, dielectric layers for capacitors and passivation coatings for electronic circuits.