Surface palladium-plated bonding brass wire

Abstract

The invention discloses a surface palladium-plated bonding brass wire comprising a brass core taking brass as a main component and a palladium layer formed by plating on the brass core. The surface palladium-plated bonding brass wire is characterized in that trace metal for improving the extension performance is added in the brass core taking the brass as the main component; a single crystal is smelt and drawn to form a brass alloy core wire; the palladium is plated on the surface of the brass alloy core wire; and the surface palladium-plated bonding brass wire is formed in a superfine drawing manner. Compared with the prior art, the invention has the benefits that the surface palladium-plated bonding brass wire has better final plasticity deformation capability in the subsequent superfine drawing process without intermediate annealing; the percentage elongation of the surface palladium-plated bonding brass wire is at least 11 percent; the deformation of a palladium-plated layer in the pressure processing flow is consistent; the surface of the surface palladium-plated bonding brass wire is uniform, compact and complete, which is especially beneficial to full deformation during welding bonding, and thus the pulling strength and the reliability are improved. In addition, the cost of products can be controlled to be about 6 yuan / 100 meters and the products have high cost performance.

Description

technical field [0001] The invention relates to a bonding wire, in particular to a bonding copper wire coated with palladium on the surface. Background technique [0002] Chinese patent CN100359657C announced a "bonding wire and an integrated circuit device using the same". A dissimilar metal layer of metal and a cladding layer comprising an oxidation-resistant metal having a melting point higher than that of copper and formed on the dissimilar metal layer. The bonding wire can be formed into a ball having a true round shape over a wide range of ball diameters, and can be fabricated using plating techniques without degrading the plating solution, and the adhesion of the cladding to the core material good. However, the integrity of the coating cannot be guaranteed in the subsequent pressure processing process. When the diameter reaches 0.05mm during stretching, the coating is destroyed. Moreover, when there is no pre-plated gold layer between the copper core material and th...

AI Technical Summary

Problems solved by technology

However, the integrity of the coating cannot be guaranteed in the subsequent pressure processing process. When the diameter reaches 0.05mm during stretching, the coating is destroyed. Moreover, when there is no pre-plated gold layer between the copper core material and the palladium layer, the electroplating solution It will soon deteriorate due to the dissolution of copper in the electroplating solution, which will affect the quality of electroplating