Influence of Cold Low Pressure Lamination Parameters on the Joining of Low Temperature Co‐Fired Ceramics Green Tapes and Sintered Alumina Substrates

Abstract

In this study, laminates consisting of sintered alumina substrates and green Low Temperature Co-fired Ceramics (LTCC) tapes have been produced via Cold Low Pressure Lamination which is based on adhesive tapes for joining of layers at room temperature and pressures <5 MPa. The influences of lamination parameters such as temperature, pressure, and time on the quality of the green and sintered multilayer stack have been determined. If the bottom LTCC layer of an alumina-LTCC-LTCC laminate is metallized by screen printing defects such as crack formation can occur due to stress formation caused by constrained sintering. By adapting the lamination parameters, these stresses can be avoided. Another defect observed is cavities which form along the printed circuit lines. This type of defect is caused by the shrinkage of the circuit line width during firing; by reducing the height of the conductor line during screen printing, the cavity size can be reduced. In addition, different screen-printed metallization layouts have been tested to determine the influence of line and spaces on the quality of sintered laminates.