Study on the degradation of welding strength in ceramic substrates subjected to temperature cycling

This article uses AlN and Al 2 O 3 thick film substrates to conduct an in-depth study of the attenuation of welding strength of ceramic substrates under temperature cycling conditions. Using the test method of miniaturizing the substrate to test the transverse shear force, the shear force changes of different substrates with different 62Sn36Pb2Ag solder thicknesses were summarized and compared with the temperature cycle process. The finite element simulation method was used to simulate the Ag/SnPb interface, and the trend of interface stress and strain changing with temperature was obtained. Finally, the study found that during the temperature cycle, the Sn-enriched phase in the solder of the AlN substrate diffuses faster into the Ag layer, so the soldering strength of the AlN substrate decays faster during the temperature cycle.