Preparation method of high-performance gold coated copper bonding wire

Abstract

The invention relates to a gold coated copper bonding wire and a preparation method thereof. The gold coated copper bonding wire is formed by combining core wire copper and a gold coating layer, the diameter of the bonding wire is 10-50 mum, and the ratio of the area of the gold coating layer to that of the cross section is 10-30%. The preparation method comprises the following steps: adopting an oxygen-free copper rod with the diameter of 5-30 mm as the core material, and adopting the reversed solidification method to prepare a gold coated copper composite wire blank; carrying out multi-pass hole pattern rolling and / or drawing processing on the composite wire blank to obtain a wire rod with the diameter of 3-8 mm, wherein the rolling speed is 10-200 m / min, and the reduction rate of the single-pass section is 10-50%, or the drawing speed is 5-50 m / min, and the reduction rate of the single-pass section is 10-30%; then, carrying out rough drawing processing and fine drawing processing on the composite wire rod formed by rolling processing and / or drawing processing to prepare the gold coated copper bonding wire; middle annealing can be exerted in the drawing process, the annealing temperature is 100-400 DEG C, and the annealing time is 10-60 min. The gold coated copper bonding wire is compact in coating layer, uniform in thickness, high in bonding strength of the interface, excellent in processability, low in possibility of web breaking and wire breaking, short in preparation technological process, high in yield and low in manufacturing cost.

Description

[0001] technical field [0002] The invention relates to a preparation method of a double-metal layered composite wire, and in particular provides a gold-clad copper bonding microwire and a high-efficiency preparation method thereof. [0003] Background technique [0004] With the rapid development of electronic information technology, the packaging of semiconductor devices and integrated circuits is developing in the direction of multi-lead, high integration, miniaturization and low cost, which puts forward higher and higher requirements for the economic and technical indicators of bonding wire. Gold-clad copper bonding wire is a new type of high-performance bonding material. It not only has the excellent bonding performance, oxidation resistance and corrosion resistance of bonding gold wire, but also has the excellent mechanical properties and electrical and thermal conductivity of bonding copper wire. With lower density and lower cost, as a substitute material for bondin...

AI Technical Summary

Problems solved by technology

[0009] The purpose of the present invention is to use the oxygen-free copper rod as the core material, adopt the reverse solidification method to prepare high-quality gold-clad copper composite wire billets, and combine the subsequent cold processing (rolling, drawing) to prepare gold-clad copper bonding microwires, which can not only solve the problem of The gold-clad copper-bonding wire-coated gold layer prepared by the current process has the problems of uneven thickness, low density and low interface bonding strength, and can simplify the process, improve the yield, and reduce production costs.