Realization method for lead bonding thick aluminum wire

Abstract

The invention relates to the technical field of the semiconductor packaging, in particular to a realization method for lead bonding a thick aluminum wire. The method comprises the following four important operation key points of designing and optimizing a chopper, detecting chip surface aluminum layer thickness, optimizing and matching a bonding technical parameter, and detecting the bonding strength. As the thick aluminum wire is unlikely to oxidize, the production technology is simplified, and the cost can be obviously lowered. Meanwhile, the thick aluminum wire has the advantages of small contact resistance, low device power consumption, high bonding strength and the like. The chip aluminum layer thickness is detected by 85% phosphoric acid solution so as to ensure that the aluminum layer thickness is more than 5.0mum when the thick aluminum wire is lead bonded, and craters can be prevented from generating in the operation process. The technical parameter adopts initial power pressure, and the craters can be prevented by regulating the initial power pressure according to the practical situation. Whether the welding strength reaches the standard is judged by measuring the breaking force of the bonding wire by a gram force meter. According to the realization method for lead bonding the thick aluminum wire, the cost can be obviously lowered, the device power consumption is lowered, and the product reliability can be improved.

Description

technical field [0001] The invention relates to the technical field of semiconductor packaging, in particular to a method for realizing high-power Schottky, fast recovery and IGBT using thick aluminum wire wire bonding in semiconductor device packaging. Background technique [0002] Gold wire and copper wire wire bonding are the most widely used wire bonding technology in the electronics industry, but gold wire and copper wire cannot meet the bonding technical requirements of high-power devices, modules and IGBT products due to cost and welding process limitations. [0003] With the development of the semiconductor industry, the power of packaged devices has been greatly increased to meet the needs of the market. The improvement of device power involves the withstand voltage capability and current flux of the inner lead. The semiconductor packaging industry first adopted thick aluminum wires to replace the previously used gold wires and copper wires. Although the gold wire ...

AI Technical Summary

Problems solved by technology

For the copper wire process, a certain cost can be saved on the basis of the gold wire, but the conditions required in the bonding process are more complicated, because the copper wire needs to be protected by a protective gas when performing bonding, which increases the cost and increases the cost. Difficulty of craft

Before copper wire welding, a copper ball needs to be sintered by electric current. Once the copper ball is oxidized, it is easy to leave craters on the aluminum layer of the chip, which will affect the quality of the product and greatly reduce the reliability of the product.

At the same time, similar to gold wires, more than 25 thick aluminum wires of 1000 μm need to be welded with 50 μm copper wires. When performing chip bonding, it is easier to bring adverse effects on the chip. Regarding the advantages and disadvantages of the above gold wires and copper wires, We propose a method for bonding thick aluminum wires of 500μm-1000μm or more, which can meet the packaging process requirements of high-power devices, and also overcome the disadvantages of gold wires and copper wires, while reducing power consumption and improving product quality. Reliability, which brings great benefits to the semiconductor packaging industry

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