Shrinkage behavior of LTCC hetero-laminates

Shrinkage behavior of various stacking configurations consisting of three dissimilar dielectric tapes with different dielectric constants of k ∼ 8.2, 14.8 and 48.2 were investigated. The shrinkage behavior has been critical as a sensitive parameter in the design of embedded microcircuit passive components. Unexpectedly low x–y shrinkages of 2.5–7% observed for the hetero-configurations are believed to be associated with the physical constraining effect that results from the dissimilar sintering route and crystallization behavior of each tape. The constraining effect found depends on the sintering temperature and the total number of each tape layer in a given hetero-structure. The tendency of slope variation in the Arrhenius plots of thermo–mechanical curves suggests that increasing the number of embedded tapes can produce a potential lower activation energy with a higher x–y shrinkage.