Interfacial strength and microstructure of AlN/Cu joints produced by a novel brazing method facilitated by porous copper layer and Ag foil

The reliability of wide-bandgap (WBG) semiconductors used as power electronics is closely related to the high thermal conductivity AlN-metalized substrates. Thus, bonding AlN ceramics with metals a key issue for production reliable This paper reports on new method producing AlN/Cu joints by employing novel film metallization process, which involves porous network Cu layer and Ag foil. microstructure phases formed at interface produced various brazing temperatures times were analyzed scanning electron microscopy X-ray diffraction analysis. Strong shear strength 48.5 MPa after 850 °C 10 min. typical interfacial reaction zone was Cu/Ag(s) + Cu(s)/CuAlO2 Al2O3 Cu(s)/AlN. experimental results manifest crucial role Ag–Cu eutectic liquid phase, between foil, deposited surface ceramic substrate, since both them effectively favor reduction in residual stresses joint result strong ceramic/metal joins.