Research on BCB/Cu thin film multilayer interconnection technology based on LTCC substrate for Microsystem Integration

Considering the requirements of Microsystems miniaturization integration for high-performance film-forming substrates, the key technologies of multilayer BCB/Cu thin film interconnection based on LTCC substrates and the related process controls were studied. A high reliability "T" interface interconnection method for thin film magnetron sputtering Cr/Cu/Cr and Cr/Pd/Au composite membrane structure and its preparation method were proposed. The effects of the interface defect and roughness of LTCC-thin film, the control of residual photoresist quantity in BCB film through holes and the stress of metallization of dielectric membrane on the quality of thick thin film composite substrate were studied. The prepared 12-layer thick thin film mixed substrate(10 layers LTCC substrate, 2 layers of thin film wiring) 60 pieces, all passed the GJB2438 C. 2.7 film substrate evaluation standard. Compared to the LTCC substrate, the wiring density is increased by 4 times, size reduced by 40 %.