Method for rapidly preparing Cu3Sn-Cu micro welding spots through high-frequency induction welding

The invention relates to a method for rapidly preparing a Cu/Cu3Sn-Cu/Cu micro welding spot. The method is characterized in that foamy copper is used as a framework, tin is used as a filling material,a composite soldering lug is manufactured according to a certain proportion, and a high-frequency induction welding process is adopted to quickly obtain a micro welding spot composed of Cu-SnIMC andthe foamy copper. Reliable connection is formed between a chip and a substrate through welding, and micro welding spots formed by compositing Cu3Sn and residual foamy copper after reaction are rapidlyobtained; the foamy copper in the connecting material can greatly increase the effective reaction area of Cu and Sn in a joint, the welding efficiency and the electrical conductivity and thermal conductivity of the joint are improved, and a solid-liquid interface reaction mechanism under the action of a skin effect generated by electromagnetic induction of high-frequency induction welding is beneficial to dissolution of Cu