Zero shrink LTCC 3D structure interconnections

This paper describes design, construction and some recent tests of three dimensional stacked lead-free soldered structures based on Low Temperature Co-fired Ceramic substrates (LTCC). These structures have a great potential to create compact structure combining multiple different modules in one package. Internal connections used in these 3D structures have an important role, because they not only provide electrical and signal connection, but they also present mechanical attachment between connected substrates. Goal of this work is to develop, simulate and evaluate new structures based on interesting “zero shrink” Heraeus HL2000 LTCC substrates, where dimples help to reduce thermo-mechanical stress and pads modified with copper to reduce problems with leaching.