Laser manufacturing method for solder bumps

Abstract

The invention provides a laser manufacturing method for solder bumps. The laser manufacturing method comprises the following steps: putting a pretreated metal base plate on a processing plane; loadingparticle solders for manufacturing the solder bumps into a solder throwing device; setting technological parameters by a computer to carry out route planning of the solder bumps; starting a laser manufacturing system to perform a manufacturing program; receiving a control signal of the computer for synchronous starting by a laser device, a control component and a solder throwing system; enablinga laser beam emitted by the laser device to pass through a galvanometer unit and a f-theta flat field focusing lens in sequence onto the processing plane to form laser spots, controlling a solder throwing arm by the solder throwing system synchronously, and throwing the particle solders in the solder throwing device to a light spot area emitted by the laser beam. The temperature of the base plateis higher than the melting point of the solders due to laser heating, and then the solders are melted; after the laser beam is moved away, due to rapid heat diffusion of the metal base plate, the temperature of the area is quickly decreased, and the melted solders are solidified to form the solder bumps; and after the operation of the manufacturing program, the manufacturing of all solder bumps onthe metal base plate is completed.

Description

technical field [0001] The invention relates to the technical field of microelectronic packaging, more specifically, to a method for making solder bumps by laser. Background technique [0002] In the field of microelectronic packaging, the fabrication of solder bumps is one of the key technologies in packaging. There are many ways to make solder bumps, mainly electroplating and metal spraying, etc. During the electroplating process, the use of photoresist increases the complexity of the manufacturing process and the manufacturing cost, and the size of simultaneous electroplating is affected by the current and is difficult to control; The technical manufacturing process of metal spraying is simple and flexible, but the equipment is complex and expensive. In recent years, with the development of laser technology, the technology of laser solder bumps has also developed rapidly. Zou Xinjue and others from Shanghai Jiaotong University introduced laser reflow into the solder bump...

AI Technical Summary

Problems solved by technology

There are many ways to make solder bumps, mainly electroplating and metal spraying, etc. During the electroplating process, the use of photoresist increases the complexity of the manufacturing process and the manufacturing cost, and the size of simultaneous electroplating is affected by the current and is difficult to control; The technical manufacturing process of metal spraying is simple and flexible, but the equipment is complex and expensive

In recent years, with the development of laser technology, the technology of laser solder bumps has also developed rapidly. Zou Xinjue and others from Shanghai Jiaotong University introduced laser reflow into the solder bump manufacturing process, and used machine vision to make solder bumps. Positioning, set up the experimental prototype of the laser-made solder bump system; Finland's Kordas.K. et al. used an argon ion laser with a power of several watts to conduct a laser-made solder bump experiment. These existing lasers make solder bumps The bump method uses lead-containing solder; most of the methods use shielding gas, the processing technology is complicated and the cost is high, and it is difficult to control the size of the solder bump

Images