CLOSED POROSITY ALUMINOSILICATE FOR ELECTRONIC PACKAGING APPLICATIONS

The electrical properties of sol-gel prepared aluminosilicate films we re investigated for suitability in electronic applications. The alumin osilicate films exhibited apparent closed porosity and a dielectric co nstant as low as almost-equal-to 5 with processing temperatures from 3 73 K to 873 K. The porosity was inaccessible to nitrogen at 77 K, heli um at 293 K, and water vapor at 293 K. Both bulk and thin-film samples were analyzed for hydroxyl and carbon contents to elucidate the relat ive dependence of the measured electrical proper-ties on processing co nditions. Experiments indicate it is possible to vary the porosity in bulk material in ways that should improve electrical properties.