Effect of glass composition on the properties of thick film resistors

摘要

Thick-film inks (TFI) for the production of hydrid circuits using screen printing technology consist of various materials. The considerable part of TFI for production of resistive or dielectric films is glass. Zinc metaphosphate glasses (ZnO:P{sub}2O{sub}5=1:1, SiO{sub}2 8-12, Al{sub}2O{sub}3 2-8 mol.%) instead of lead borosilicate glass, used in industry now for TFR, have been investigated. The thick-film inks have been deposited by screen printing to the alumina substrate Rubalit 708. DSC- and TG analyses show, that there is not chemical interaction between glass-RuO{sub}2, glass-alumina substrate. The SEM-micrographs shown that already for the shortest time at sintering temperature /850°C/ was detected a complete saturation of the glass phase with RuO{sub}2. The tendency to increase the distribution of RuO{sub}2 in direction to (RuO{sub}2 + glass)-layer remains with increasing of duration time at sintering temperature. The layer near the substrate has a relative small content of Ru and a high content of Al, obviously, owing to diffusion of Al from substrate. The small changes in distribution of P and Si have been determined. The TFI were obtained from the glass and RuO{sub}2 mixture by addition of the screening agent. The resistive inks from Zn-metaphosphate glass have been prepared and printed with Au and Ag electrodes. Owing to the suitable thermal, electrical properties and viscosity, the zinc metaphosphate glasses could be applied in production of TFR on RuO{sub}2 basis.