Additive-Driven Sinterability Improvement of Mullite Ceramics for Co-firing with Cu-Mo

摘要

The needs for electrodes and materials to realize a low resistance are increasing as the line widths of a circuit are reduced for an increase in the number of layers due to increasingly higher integration of semiconductor wafers as well as impedance matching of transmission lines. Consequently, Cu-Mo electrodes have been considered for application to realize a lower resistance than that of the existing Mo electrodes used with mullite materials. When mullite ceramics and Cu-Mo electrode were simultaneously fired, resistivity was not reduced because of interaction between the electrode and the ceramic at 1400 °C, while resistivity decreased below 1370 °C. It was verified that sintering should be conducted at a temperature as low as 1350 °C to realize a low resistance by applying Cu-Mo electrodes to the mullite ceramics. When sintering was conducted at 1350 °C with addition of 1 wt % of SiO2, 1 wt % of MgO, 1.5 wt % of Y2O3 and 7 wt % of SrCO3 to mullite, an excellent sinterability was exhibited at a density of 3.22 g/cm~3.