A multilayer low pass filter fabricated by ferrite and ceramic cofiring system based on LTCC technology

LTCC (Low Temperature Co-fired Ceramics) has been become the key technology of packaging for the integrated of passive components due to its higher performance of thermal sink, reliability and plays an important role in increasing higher frequency, decreasing the loss, minimize the volume, etc. This paper mainly focuses on the design and fabrication of low pass filter based on ferrite and ceramic cofiring system by LTCC technology. Firstly, the match conditions of co-firing characteristics for ferrite and ceramic cofiring system were carefully studied by TMA measurement and the excellent shrinkage controlling was obtained. The low-pass filters with cut-off frequency at 120 MHz were fabricated using Co/Ti doped barium ferrite and ULF140 material as the dielectrics to further validate the circuit model and the samples were tested with high consistence with the simulated data.