Control of De-Lamination Phenomena in LTCC Zero-Shrinkage by Glass Infiltration Method

A zero-shrinkage sintering process in which the shrinkage of x-y axis is controlled to be zero is in great demanddue to the trend of high integration in the ceramic modules. Among the zero-shrinkage sintering processes that areavailable, the proposed glass infiltration method where the viscous but fluidic glass infiltrates of the Al2O3 particles inthe structure of Al2O3/glass/Al2O3 during firing is one of the applicable methods. However, the above proposed glassinfiltration method has the problem of the warpage-like delamination. This occurred at the outermost surface of themultiple-bundle substrate. It is thought that the decomposed gas rapidly expands in low viscous glass to create vacantspace. To solve this problem, the vacant space was tamped with Al2O3 particles to lead to the actual improvement ofthe sintered properties. With 15 wt% of tamping Al2O3 particles in glass, most of the vacant space disappeared. Fullydensified zero-shrinkage substrate without delamination can be obtained.