大尺寸LTCC 基板高钎透率焊接工艺研究

低温共烧多层陶瓷（Low Temperature Co-fired Ceramic, LTCC）技术在军工电子领域的应用越来越广泛，但是大尺寸多腔体LTCC 基板的钎透率一直是制约LTCC 基板应用范围进一步扩展的重要因素。文中研究了基板可焊性、平面度以及回流焊接工艺等因素对LTCC 基板钎透率的影响规律，并在此基础上完善了大尺寸多腔体LTCC 基板的回流焊接工艺。基板与壳体焊接一次成形，有效控制了焊料流淌；基板钎透率达到95% 以上，避免了对焊缝和多余焊锡的返工返修工作。这些都推动了大尺寸多腔体LTCC 基板在微波组件中的批量应用。

Research on High-brazing Rate Process of Large-size LTCC Substrate

The low temperature co-fired multilayer ceramic (LTCC) technology has been widely used in the field of military electronics, but the brazing rate of large-size LTCC substrate with multi-cavity has restricted the application of LTCC substrate. In this paper the effects of substrate solderability, planarity and reflow brazing technology on brazing rate of LTCC substrate are studied and the reflow brazing technology of large-size LTCC substrate with multi-cavity is improved. The LTCC substrate and shell are brazed well with once forming and thus the flux of the solder is effectively controlled. The brazing rate of the LTCC substrate is over 95% and thus the repair of the brazing seam and excess solder is avoided. For these, the application of large-size multi-cavity LTCC substrate in microwave modules is promoted.