Thick Film Process Characterization for Thin Film Metallized LTCC
Low temperature cofired ceramic (LTCC) technology has proven to be invaluable in military/space electronics, wireless communication, microsystems, medical and automotive electronics, and sensors. The use of LTCC for high-frequency applications is appealing due to its low losses, design flexibility, and packaging and integration capability. The LTCC thick film process is summarized, including some unconventional process steps such as feature machining in the unfired state and thin film definition of outer layer conductors. The LTCC thick film process was characterized to optimize process yields by focusing on the following factors: (1) print location, (2) print thickness, (3) drying of tapes and panels, (4) shrinkage upon firing, and (5) via topography. Statistical methods were used to analyze critical process and product characteristics to achieve the optimization goal.