Suppression of crystal growth in low dielectric inorganic composition using ultrafine alumina

摘要

A ceramic composition for forming a ceramic dielectric body having a dielectric constant of less than about 5.0 and a TCE of 2.0-4.0 ppm/c. The composition is formed from a mixture comprising 25-50 weight percent of a low temperature glass selected from the group consisting of borosilicate glass, zinc borate glass and combinations thereof, 50-75 weight percent of a high temperature glass selected from the group consisting of high silica glass, titanium silicate glass and combinations thereof, and 1-10 weight percent of ceramic material having a particle size of less than about 3 microns. The mixture can be combined with a polymeric binder to produce an unfired green tape which is co-fireable with high conductivity metallurgies such as gold, silver and silver/palladium. A preferred ceramic material is colloidal alumina.