Study of direct soldering of Al2O3 ceramics and Cu substrate by use of Bi11Ag2La solder

The work is devoted to the study of direct soldering of a substrate of Al2O3 ceramics with a Cu substrate by use of Bi11Ag2La solder. Soldering was realised by fluxless method in air by activation with power ultrasound. It was found out that lanthanum is during the ultrasonic soldering process distributed to the interface with Al2O3 substrate, enhancing thus the bond formation. The bond with ceramic substrate has adhesive character without formation of a new contact interlayer. The shear strength of joint with Al2O3 ceramics is 20 MPa.