With the development of science and technology, electronics, electrical and digital products are increasingly mature and swept the world, the products covered by the field of any components it may involve the soldering process, large PCB board, Components, the vast majority of the welding needs to be completed below 300 ℃.
Now the electronics industry's chip-scale package (IC package) and board-level assembly are a large number of tin-based alloy filled with metal welding, complete the device package and card assembly. For example, in a flip chip process, the solder directly connects the chip to the substrate; in the manufacture of the electronic assembly, the device is soldered to the circuit substrate using solder.
Soldering process, including wave soldering and reflow, etc., wave soldering is the use of molten solder flow of the peak surface, and the components of the PCB with the PCB surface contact with the completion of the welding process; reflow is the solder paste or solder The sheet is placed between the PCB pads in advance, and the components are connected to the PCB by heating the solder paste or the solder sheet.
Laser soldering is a brazing method in which laser is used as a heat source and a molten tin is used to achieve a close fit.
Compared with the traditional soldering process, this method has the advantages of fast heating speed, small heat input quantity and little heat effect. The welding position can be precisely controlled; the welding process is automated; the amount of solder can be precisely controlled and the solder joint consistency is good; The impact of volatiles on the operator during the welding process; non-contact heating; suitable for complex structural parts welding and so on.
Laser soldering to laser heat source as the main body, filling the molten metal melt to achieve the connection, conduction, reinforcement of the process effect. According to the state of tin material can be divided into three main forms: tin wire filling, solder paste filling, solder ball filling.
Tin wire filled with laser soldering applications
Winding laser welding is a major form of laser soldering, wire feeding mechanism and supporting the use of automated workstations, through the modular control mode to achieve automatic feeding wire and light welding, with a compact, one-time operation characteristics, compared to In several other soldering methods, its obvious advantage is a one-time clamping material, automatic welding, with a wide range of applicability.
The main application areas are PCB circuit boards, optical components, acoustic components, semiconductor refrigeration components and other electronic components soldering.
Paste Filler Laser Soldering Applications
Paste laser welding is generally used in the reinforcement of parts or pre-tin, such as the edge of the shield through the solder paste in the high temperature melting reinforcement, magnetic contacts on the tin melt;
Also applies to the circuit conduction welding, for the flexible circuit board welding effect is very good, such as plastic antenna seat, because it does not exist complex circuit, through solder paste welding often achieve good results. For precision miniature parts, solder paste filling can fully reflect its advantages.
As the solder paste heat uniformity is better, the equivalent diameter is relatively small, through the precision dispensing equipment can accurately control the amount of small tin, solder paste is not easy to splash, to achieve good welding results.
Based on a high concentration of laser energy, solder paste heat splash splash, splashing tin beads easily lead to short circuit, so the quality of the solder paste is very high, can be used to prevent splash solder paste to avoid splash.
Solder ball filled with laser soldering applications
Laser solder ball is a solder method that places the solder balls in the mouth of a solder ball, which is melted by laser heating and falls on the pad and wetted with the pad.
The solder balls are non-dispersible pure tin small particles, the laser heating and melting will not cause splashing, solidification after the full sleek, there is no follow-up pad or surface treatment and other additional processes.
Through this welding method welding small pad and enameled wire soldering can achieve good welding effect.
Application of Laser Soldering Technology
The traditional soldering, including wave soldering, reflow soldering, hand soldering tin soldering can solve the soldering process problems Laser soldering can be gradually replaced, but like patch soldering (mainly reflow), the current laser welding process is not applicable, Due to some of the characteristics of the laser itself, but also makes the laser soldering process more complex, specifically summarized as:
1) for the fine subtle soldering, workpiece positioning and clamping difficult, welding and production is difficult;
2) laser high energy density easily lead to damage to the workpiece, especially for PCB board soldering, substrate and metal embedded structure is very easy to burn board, high sample rate of high cost so that customers can not accept;
3) the high concentration of laser energy can easily lead to solder paste splashing, PCB board soldering can easily lead to short-circuit products lead to scrapped;
4) for the soft wire class, clamping positioning consistency is not good, solder fullness and appearance of large differences;
5) precision soldering often feed wire filling tin material requirements, 0.4 mm wire diameter of the wire automatically wire difficult.
Overview of Laser Soldering Market Demand
Laser soldering at home and abroad have different degrees of development, despite the development of these years, there is no big leap and application development, have to say that this is a soft application of welding applications.
However, the market demand is changing, not only the existence of a vertical number of growth, but also the application of horizontal applications are constantly expanding to electronic digital products related parts of the demand for lead-based process.
Covering other parts of the industry parts soldering process needs, including automotive electronics, optical components, acoustic components, semiconductor refrigeration devices, security products, LED lighting, precision connectors, disk storage components;
In terms of customer base, which led to the relevant parts of Apple products related to the demand for tin-related process, including its upstream industry chain have also been looking for laser soldering process solutions, on the whole, laser soldering in the present and future A long time there will be surprising explosive growth and the larger market volume.
The global economic weakness of the moment, Apple thriving, the huge market share of digital electronic products and the huge global large-scale procurement led to a large number of business growth, the main products of these enterprises is the electronic components, soldering is its production An indispensable part of the process.
Urgent process breakthrough demand
Including Apple's suppliers such enterprises, the production of products is the latest high-end design, in the mass production process will encounter tricky process problems, the need for improvement and improvement.
A very typical area is the storage component industry, the head is a very sophisticated and process requirements are very high storage parts, the head of the data cable is generally flexible PCB, affixed to the steel body, one end of the array Of the fine points to be pre-tin, slightly on the amount of tin can only be observed under the microscope, and the effect of welding is extremely strict.
The traditional welding method is manual welding, the operator's welding level is very high, the shortage of labor resources and liquidity to the production of great uncertainty, Moreover, can not quantify the process standards (no process parameters, relying entirely on artificial sensory judgments Welding effect), so the need for new welding technology to overcome technical barriers.
Process upgrades and scalability needs
Laser soldering energy process parameters, improve yield, reduce costs and ensure the standardization of production operations. With the Chinese market to enhance the cost of labor and the scarcity of skilled personnel, the traditional soldering field of artificial needs slowly transformed into mechanized operations demand, laser soldering will break through the traditional process, leading the flair. From the current situation of customer welding samples, laser solder penetration is also the general trend.
in conclusion
As the laser soldering with traditional solder soldering unparalleled advantages, will be in the field of electronic interconnect to be more widely used, with great market potential.
