PCB News - FPC and Rigid-flex Board to grasp the future new business opportunities of the global circuit board industry

FPC and Rigid-flex Board to grasp the future new business opportunities of the global circuit board industry

With the vigorous development of electronic technology, printed circuit boards (PCB) are not only an important player in the supply chain, but also one of the important industries in Taiwan today. Even with the impact of the novel coronavirus pneumonia epidemic in 2020, although the supply of upstream materials related to circuit boards was once affected by the suspension of work, but in the case of rapid resumption of work and most manufacturers still have production capacity deployment in other unaffected areas, the raw materials The supply impact is slight.

However, the new type of coronary pneumonia has not only changed the investment thinking of circuit board manufacturers, but also adjusted the product structure or production layout to accelerate digital transformation; it also benefited from long-distance business opportunities, 5G, high-performance computing, the cloud, the Internet of Things, and automotive electronics. The emergence of demand and the continuation of competition between the United States and China will affect the development of the global circuit board industry.

In particular, compared with other hard-board circuit board products, the soft board has the characteristics of lighter, thinner and more flexible products. With the trend of end products demanding light, thin and multi-tasking, the application field of soft boards is increasing year by year. According to the statistics of the Industrial Technology Research Institute, the global output value of circuit boards in 2020 will be about 69.7 billion U.S. dollars, of which soft boards (including flexible and hard boards) account for about 20%, and the output value will reach 14 billion U.S. dollars.

Compared with the earlier application of FPC, the application demand focuses on the parts that need to be bent or sliding, such as CD-ROM drives, hard disk drives, printers or flip/slide phones. With the popularization of mobile devices and emphasis on light and thin multi-tasking, FPC is used in electronic products. It plays a more important role. In addition to the increase in the number of soft boards used in each terminal electronic product, the specifications including line width and line spacing, electrical characteristics, component integration, and reliability requirements have all been improved. Therefore, regardless of whether the soft board or Rigid-flex boards are all products with strong growth potential in the global circuit boards in recent years.

As the application range of FPC is gradually expanding, it is no longer limited to hard disk drives, smart phones, etc., and the demand for niche products including automobiles and biomedical equipment is gradually increasing. This has attracted more manufacturers to enter the ranks of FPC production, but Under the characteristics of automatic production and large-scale production of flexible boards, which have more obvious advantages than other products, the trend of Evergrande, a big manufacturer, is expected to continue to develop.

At present, FPC and Rigid-flex PCB are also in the stage of rapid improvement in product specifications (electricity, number of layers, line width/line spacing, integration). In the future, they will move toward high density (High Density) and high frequency (High Speed). /Frequency) and multi-function (Multi-function) and other three trends. The descriptions are as follows:

■ High Density

As mobile phone lens pixels have generally increased to more than 10 million pixels, most of the mobile phone lens chips are packaged in COB, so most of them have changed to using rigid-flex boards; also because the technical difficulty of rigid-flex boards is much higher than that of traditional flexible boards, The average unit price is higher, and there have been fewer manufacturers in the past. According to the development blueprint for flexible and hard board technology published by the Taiwan Circuit Board Association in 2019, under the current situation of copper thickness of 15-18 μm, the line width/line spacing of the inner circuit is about 40/45 μm, and it is estimated in 2023 Under the same copper thickness, the line width/line spacing of the inner layer circuit will be reduced to 30/40μm, and the line width/line spacing of the outer layer circuit will also drop from 40/40μm in 2019 to 30/40μm in 2023. In addition, in terms of the number of layers, most of the soft boards are already double-layer boards or multi-layer boards. The layer structure after combining with hard boards is from 6 layers (2F+2R) to more than 9 layers (3R+3F). +3R), or even 10-layer (4R+2F+4R) products are also used by customers.

■ High Frequency (High Speed／Frequency)

Generally speaking, it is used for PCBs with frequencies above 1GHz or wavelengths less than 0.1 meters, which can be called high-frequency circuit boards that need to prevent signal loss material support. Usually, they must have a lower dielectric constant (Dk) and dielectric loss (Df). ), low humidity to prevent excessive water absorption, quality uniformity, etc., such as common Bluetooth communications, servers, wireless networks, and even some smart phone antennas; as for future application requirements, there will be more and more space satellites, automotive ADAS For systems and 5G mobile communication networks, due to higher electromagnetic frequencies (10GHz～100GHz) and shorter wavelengths (0.001m～0.01m), the requirements for high frequency and low loss materials are more stringent.

■ Multi-function (Multi-function)

With the development of electronic modules in the direction of multi-functions, the number of components that need to be matched is also increasing. However, due to the limitation of the space of mobile terminals, burying the components is also one of the solutions. Regardless of whether the IC is concealed in the IC carrier board, or passive components such as capacitors, resistors, and inductors are concealed in the printed circuit board, the built-in component technology has been developed for at least many years. The advantages of the built-in component technology for the system mainly include: 1. Improve the quality of the line signal: the use of the built-in component technology to place the noise source in the PCB can reduce the occurrence of noise to a limited extent; and the processing of high-frequency signals can also be transparent. The structure of the stack perforation shortens the signal path and ensures the quality of the high-frequency signal. 2. Reduce EMI and power supply stability. 3. Reduce area and reduce power consumption.

All in all, both FPC and FPC are products with strong growth potential in the global circuit boards in recent years. However, due to the high correlation between the two products and smart phones, they are also easily affected by smart phones. However, there are still great business opportunities in the long-term.

In the face of the post-5G and 6G application trends, since communication equipment to mobile devices need to process higher frequency signals, the PCB board materials must be more able to reduce signal loss; and in electric vehicles and other new energy vehicles In the application scenario, the demand for compound semiconductors and high-power environments is brought about, and the heat dissipation performance of the circuit board has become a major issue. In order to meet the application of circuit board related technologies in the future, Taiwan's PCB industry urgently needs to make breakthroughs in order to avoid creating gaps in the supply chain.