The Effect of Firing Temperature on Structure and Electrical Properties in Low Temperature Co-fired Ceramics

摘要

An LTCC tape dielectric (A6M) was fired stepwise from 775°C-925°C using standard industry profiles. The fired tapes were investigated for shrinkage, density, crystallization (XRD), composition distribution (SEM/EDS), and high frequency (10 GHz) electrical properties. The tape consists of a glassy material that undergoes crystallization upon firing. Two crystalline phases were observed along with residual glass. Both crystallized phases appear to alter their unit cell dimensions with firing temperature. Fired tape density and XY-shrinkages were stable over the temperature range studied. Electrical properties (ε_r, tan 6) were stable above 825°C including and up to the maximum temperature studied.