Since its inception in the mid-1960s, Pcb manufacturing has become the mainstream of today's electronic manufacturing technology after more than 50 years of development, and is continuing to develop in depth. The development trend of its Pcb manufacturing is mainly reflected in the following aspects.
1, green production
With the implementation of the Directive on the Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment (RoHS), the Pcb manufacturing process is rapidly evolving toward lead-free, SnAgCu lead-free solder, anisotropic conductive adhesive, and various directions. Both the opposite conductive film and the solder resin conductive material have been put to practical use. At the same time, in order to achieve true lead-free, the process materials, components, production equipment, testing methods and equipment that are compatible with it are constantly improving and have entered the practical stage.
2. Development of components
With the advancement of electronic component research and development technology, components are moving toward smaller size and higher integration. The package form of components is also smaller, lighter and more frequent with assembly products. The requirements for stronger anti-interference and higher reliability continue to develop.
The modularization of SMC is the future development direction of components. As the component size has increasingly faced the limit, the precision of automatic production equipment has also reached the limit, and the chip component composite and modularization will be rapidly developed and widely applied. At present, the applications of Inch 0603, 0402 and 0201 on PCB boards are very common, but 01005 is close to the limit of equipment and process. Therefore, 01005 is only suitable for assembly process of modules and high-performance mobile phones.
The development of integrated circuit packaging technology is also very fast, from Double In-line Package (DIP) to surface-mounting devices (SMD), SMD has rapidly developed to small, thin and fine pitch; pin pitch from the past 1.27mm, 1mm.0.86mm.0.65mm to the current 0.5mm, 0.4mm, 0.3mm development; pin arrangement from the peripheral pin to the bottom of the device ball grid array pin; in recent years, two-dimensional, three-dimensional development The emergence of Multi Chip Module (MCM), Package on Package (POP), and finally the development of the System on a Chip (SOC).
With the maturity of Pcb manufacturing technology, especially the development of PCBs with low thermal expansion coefficient and special solder and filling materials, the technology of directly mounting bare chips on PCBs has developed rapidly. Currently, bare chip technology mainly has on-board chips (Chip). On Board.COB) technology and flip chip (FC) technology, which will become the mainstream of chip applications in the 21st century.
3, the development of production equipment and technology
In order to adapt to the placement of new components, the placement accuracy of production equipment is getting higher and higher, and the technology for mounting ultra-fine pitch components is becoming more and more mature (such as 0201 chip components and integrated circuits with a lead pitch of 0.3 mm). Etc.), manufacturing process technology continues to improve, through-hole reflow soldering process and selective wave soldering process are more and more widely used.
In short, with the development of miniaturized high-density packaging, with the emergence of new components, some new technologies and new processes have also emerged, greatly promoting the improvement, innovation and development of surface assembly technology, making it more Advanced and more reliable development.