PCB Blog - Analysis of PCB Market and Technology Development

Although circuit board (PCB) is rarely the leading role on the table, in fact, it is the main support for the installation and interconnection of electronic components and is an indispensable basic part of all electronic products. From mobile phones, and PDAs, to personal computers, as long as it is an electronic product, PCB is almost indispensable.

Take Taiwan as an example. As early as 2004, the output value of the PCB-related applied materials industry had reached 45.27 billion Taiwan dollars. Its output value accounts for 35.8% of the total output value of Taiwan's electronic material industry, ranking first among the six major industries in Taiwan's electronic material industry. As for the output value of the PCB materials industry, it has created extremely outstanding achievements. The output value of electronic glass fiber cloth, flexible copper clad laminate and IC carrier plate (PCB) ranked the top 3 in the world in that year.

Since last year, due to the sharp rise in the international copper price and the growth of application products, PC upstream raw materials such as copper foil substrates, which account for a large amount of upstream raw materials, have seen their prices rise and shipments increase. In 2006, Taiwan's market size of printed circuit board materials reached NT $77.7 billion, an increase of nearly 21% over 2005.

In 2007, as the prices of raw materials such as copper foil and glass fiber yarn/cloth rose steadily, the sharp price increases of substrate manufacturers will be reduced, and relevant manufacturers will also be able to have greater price competitiveness. Although the first quarter of 2007 is a traditional slack season, with the help of the sharp growth in demand for consumer products, the output value of PCB in the first quarter increased by 7% compared with the same period last year. As for soft PCB, Because the growth of mobile phone products is slowing down and the price of LCD soft boards is declining, the growth rate is only about 1%, while for IC carrier boards, the growth rate is about 2% because the supply is still oversupplied.

In recent years, due to the rise of green environmental protection ideas, the pursuit of environmental protection in raw materials has also become one of the development trends. For example, Japan's JPCA Exhibition has a considerable number of environmental resource recovery technologies on display. In the development of general technology, the pursuit of high-frequency, high heat resistance and high performance is also the direction of efforts of large PCB manufacturers, while consumer products are pursuing thin volume, The thin development of materials and PCB itself will also be one of the key trends.

In the manufacturing of general hard board PCBs, the materials have not changed much. They are basically composed of copper foil substrate (CCL), copper foil, film and various chemical products. In terms of the proportion of raw material costs, the copper foil substrate accounts for the highest cost, which varies from 50% to 70% depending on the number of layers. The main components of copper foil substrate are glass fiber cloth and electrolytic copper foil. The function of glass fiber cloth is to strengthen its hardness, and its material is made of glass fiber yarn by flat weaving.

The domestic PCB industry has developed for more than 30 years. The upstream, middle and downstream industrial structure is complete. Taiwan manufacturers have been working in the field of glass fiber yarn and glass fiber cloth for a long time. At present, they have achieved a leading position in the global industry. Electrolytic copper foil is one of the basic materials for the electronic industry. Because its copper foil substrate is an essential material for PCB, the quality requirements are quite high. It is required not only to have heat resistance and oxidation resistance but also to have no pinholes and wrinkles on the surface. It must have a high peel strength with the laminate and must be able to form a printed circuit with general etching methods, without dealing with substrate pollution such as particle migration, It belongs to copper processing materials with a high technical level.

As for copper foil substrate, which is the most important key to making up PCB, its classification is distinguished by the difference in raw materials and flame resistance characteristics. In terms of the use of raw materials, according to the different reinforcement materials of the board, it can be divided into five categories: paper-based, glass fiber cloth-based, composite base (CEM series), multilayer board base and special material base (ceramics, metal core base, etc.). According to the different resin adhesives used for the base plate, the common paper-based (insulating paper as reinforcement material) CCI includes phenolic resin (XPc, XxxPC, FR-1, FR-2, etc.), epoxy resin (FE-3), polyester resin, etc. In terms of the glass fiber cloth, epoxy resin (FR-4, FR-5) is the most widely used substrate type. In addition, there are other special resins (glass fiber cloth, polybasic amine fiber, non-woven cloth, etc. added as materials). These special resins include Gemalais. Imine modified triamcinolone? Resin (BT), polymer? Imine resin (PI), diphenylene ether resin (PPO), maleic anhydride imine styrene resin (MS), polyisocyanate resin, polyolefin resin, etc.

At present, the functions of electronic products are becoming more and more complex, and the requirements for frequency and performance are also getting higher and higher. In order to meet the above requirements, PCB should also take into account the product shape, so almost all of them are developing towards multilayer boards. Therefore, the copper foil substrate based on glass fiber cloth is the mainstream of the current market.

According to the fire resistance characteristics, it can be basically divided into flame retardant (UL94-VO, UL94-V1) and non-flame retardant (UL94-HB) substrates. In recent years, as more attention has been paid to environmental protection, a new type of bromine-free CCL has been identified among flame retardant CCLs, which can be called "green flame retardant CCL". With the rapid development of electronic product technology, there are higher performance requirements for CCL. Therefore, according to the performance classification of CCL, it can be divided into general performance CCL, low dielectric constant CCL, high heat resistance CCL (L of the general board is above 150 ℃), low thermal expansion coefficient CCL (generally used on packaging substrate) and other types.

As early as the 1960s and 1970s, flexible printed circuit boards were widely used in the automotive and photographic industries. In the beginning, they were only used as substitutes for cables and winding wires, with a low level of technology. By the 1980s, the scope of application and the level of technology were gradually raised. The product applications were extended to telecommunications products and military products, and some even began to use automated processes. After the 1990s, with the advent of the information age, soft circuit boards have new uses, such as portable mobile devices and laptops, under the demand of emphasizing high functions, small size and lightweight. In addition, LCD panel COF technology and IC structure loading board are also one of the main applications of flexible PCB.

A flexible printed circuit board (FPC) is composed of an insulating substrate, adhesive and copper conductor. Because it is composed of an insulating substrate, adhesive and copper conductor, it can also be called a flexible printed circuit board because it is flexible. Flexible printed circuit boards are characterized by three-dimensional wiring, which can be embedded into processed conductors in a free shape with equipment, and generally three-dimensional wiring, which can be embedded into processed conductors in a free shape with equipment, as well as flexible, light and thin characteristics that can not be achieved by ordinary hard laminated boards. Generally speaking, soft PCB can be divided into single-sided, double-sided, multi-layer and mixed soft and hard products.

In the application of single-sided soft PCB materials, since there is only one layer of conductor, the covering layer is optional. The insulating substrate materials used vary with the application of products. The commonly used insulating materials are polyester, polyimide, polytetrafluoroethylene, soft epoxy glass fiber cloth, etc. The double-sided flexible PCB adds two layers of conductors. As for multi-layer flexible PCBs, multi-layer lamination technology can be used to achieve a structure of three or more layers. Multilayer flexible PCBs can be divided into three types according to their flexibility. Hybrid PCB, it combines soft PCB and hard PCB. Soft PCB is laminated inside multi-layer hard PCB, which reduces weight and volume, and has high reliability, high assembly density and excellent electrical characteristics.

In order to realize the miniaturization of portable electronic products, in addition to the need to further promote high-density wiring of PCB, in recent years, there has also been a shift in PCB morphology from the original planar component 2D to the three-dimensional multi-axis 3D installation characterized by flexible substrate (FPC), which can reduce the space occupied by components and substrates in the product. The hardboard flexible substrate technology, which is a combination of 3D-mounted flexible PCB and hardboard multilayer PCB, has been rapidly and widely used in recent years.

Due to the rise of the green trend and the EU RoHS specification, the lead-free process has actually had a considerable impact on PCB. According to the properties of laminated materials, some PCBs (especially large and complex thick circuit boards) may have higher failure rates such as delamination, lamination fracture, Cu crack, and CAF (conductive anode wire whisker) failure due to higher lead-free welding temperature. PCB surface coating material also has a great impact.

In general practical application, it is observed that the joint between the welding and Ni layer (from ENIG coating) is easier to break than the joint between welding and Cu (such as OSP and silver immersion), which also indirectly leads to a comprehensive failure phenomenon similar to Microsoft Xbox 360. More attention should be paid to the design of electronic products to avoid such problems. Especially under mechanical impact, such as the drop test, lead-free welding will generally also cause more PCB cracks. The PCB industry is bound to face the challenges brought by this green process trend, so more breakthroughs must be made in the design concept of material application.

Last year, due to the rise in the copper price, the cost pressure on PCB related industries increased. Although it has slowed down this year, the price of crude oil has gradually soared. This year, PCB materials are again facing the pressure of price rise, which has exceeded the scope of PCB manufacturers' self-absorption. However, Taiwan's access to key materials is often limited by foreign suppliers, so its competitiveness is bound to be affected, Faced with the competition from other countries such as the mainland, Japan, South Korea and so on, Taiwan's PCB factories have formed their worries.