The manufacturing process of rigid-flex PCB is different due to the different types of substrates. The main processes that determine its performance are fine-line technology and microporous technology. With the requirements of the miniaturization, multi-function and intensive assembly of electronic products, the manufacturing technologies of rigid-flex PCBs and embedded flexible PCBs aiming at high-density combination are widely concerned about the high-end PCB technology at present.
Rigid-Flex PCB, namely RFC, is the printed circuit boards which combines rigid PCB with flexible PCB, and it can form the interlayer conduction through the PTH.
After continuous development and improvement, a variety of new types of rigid-flex PCB manufacturing technology continues to emerge. Among them, the most common and the most mature manufacturing process is to use rigid FR-4 as the rigid substrate of the outer board of the rigid-flex PCB, and to spray the solder ink to protect the circuit graphics of the rigid PCB part. The flexible PCB part uses the PI film as flexible core board, and polyimide or acrylic film to cover. The adhesive uses the low-flow prepregs, and finally these substrates are laminated together to make a rigid-flex PCB.
In the future, rigid-flex PCB will develop towards the direction of ultra-thin, high-density and multi-function, so as to drive the corresponding industrial development of materials, equipment and process in the upstream industry. With the development of material technology and related manufacturing technology, flexible PCB and rigid-flex PCB develop towards interconnection, mainly in the following aspects.
1) Research and development of the high precision machining technology and the low dielectric loss material.
2) Breakthrough of polymer material technology to adapt to the higher requirements of the temperature range.
3) Very large devices and flexible materials produce larger and more flexible PCBs.
4) Increase the mounting density and enlarge embedded components.
5) Mixed circuit and optical PCB technology.
6) Combined with printed electronics.
To sum up, the manufacturing technology of rigid-flex printed circuit board (PCB) has made continuous progress, but also encountered some technical problems. However, with the continuous development of electronic product technology, the manufacturing technology of flexible PCB has been continuously improved and improved, and the manufacturing cost has been reduced. At the same time, the emergence of new materials and new technology will promote the use of flexible circuit board further development, so that the application of rigid flexible printed circuit board into a virtuous cycle.
