Gold-coated-sliver base bonding silk thread and manufacture method thereof

Abstract

The invention discloses a bonding silk thread product which takes sliver silk thread as a base material and is coated by a pure gold anti-oxidation protective layer on the surface thereof. The silver silk thread product comprises the following components in weight percent: 1.8%-10.0% of gold, and the balance silver. The manufacture method thereof comprises the following steps of purifying, preparing a monocrystal silver rod, coarse drawing, heat processing, surface gilding, fine drawing, heat processing, surface cleaning, decoiling and the like. The patent of invention abandons the outmoded technique that the silk thread is directly used after being plated by a traditional thinking mode; and the silk thread is electroplated with a pure gold anti-oxidation protective layer with a certain thickness after being prepared into silver silk thread with diameter being smaller than 1mm, and then precisely drawn into the gold-coated-sliver base bonding silk thread products with different specifications by multiple procedures. The plating layer of the product has compact and even material, greatly improved bonding strength with base materials and effectively prolonged product quality guarantee period; the manufactured silk thread has proper hardness and good soldering balling property; the cost of the silk thread is less than 1 / 3 of that of the pure gold boning silk thread; The technology in the invention can be widely used in preparing bonding silk thread products in composite structures.

Description

technical field [0001] The invention relates to the technical field of manufacturing bonding wire products used in the subsequent packaging process of microelectronics, in particular to a composite structure of bonding wire products and a manufacturing method thereof. Background technique [0002] The bonding process of the microelectronic device chip refers to welding the two ends of the bonding wire to the chip pad and the lead frame pins respectively by ultrasonic pressure at a certain temperature to realize the connection between the internal circuit of the chip and the external circuit. At present, traditional bonding wires are mostly made of pure gold, which is widely used due to its advantages of high electrical conductivity, corrosion resistance and good toughness. However, with the increasing scarcity of gold resources and rising prices, the cost of microelectronic packaging has risen sharply. For this reason, colleagues have already begun to seek metal materials w...

AI Technical Summary

Problems solved by technology

[0003] The technical problem to be solved by the present invention is to overcome the defects and deficiencies of high cost and scarce resources that existing bonding wires of middle and high-end microelectronic products are all made of pure gold, and provide the society with a silver wire as the base layer, The manufacturing method of the bonding wire product covered with pure gold anti-oxidation protective layer, in order to make full use of the property that the electrical conductivity of silver is superior to that of gold, and under the premise of carrying the same rated current, further reduce the diameter of the bonding wire and shorten the welding distance , more suitable for high-density integrated circuit packaging; and due to the replacement of base metal, it can greatly reduce the cost of packaging materials for mid-to-high-end microelectronic device chips

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