Advances in Low-Temperature Co-Fired Ceramics for Next-Generation Electronics Applications

Low-temperature co-fired ceramics (LTCC) with unique multilayer interconnection architectures are indispensable for electronic communication devices and high-density integrated packaging, facing stringent demands in millimeter-wave and higher-frequency applications. This review highlights recent advances in optimizing the comprehensive performance of LTCCs and proposes strategies for further enhancement to meet the ever-growing demands of high-performance microwave devices and systems. Specifically, LTCC material designs tailored to achieve desirable properties are discussed, including appropriate permittivity, low dielectric loss, a near-zero temperature coefficient of resonant frequency, high thermal conductivity, matched coefficient of thermal expansion, and excellent mechanical strength. Additionally, innovations in sintering technologies are highlighted, such as ultra-low temperature co-fired ceramic (ULTCC) technology and cold sintering process (CSP). These approaches further reduce sintering temperatures, enabling LTCCs to integrate with a broader range of materials (e.g., silicon chips, aluminum electrodes, 2D materials, and polymers) that were previously incompatible with traditional high-temperature processes. Finally, this review offers insights into the future development directions of LTCCs in emerging applications, including 3D integration and advanced packaging, integrated communication and sensing systems, and millimeter-wave/terahertz integrated miniaturized devices for next-generation electronics.