circuit board (pcb) become the protagonist of mesa although rare, but in fact, the circuit board is to provide electronic components during installation and connection of the main support body, is the foundation of all electronic products indispensable parts, small from mobile phones, pdas, big to a personal computer, as long as it is electronic products, almost always little not the existence of the PCB.
In Taiwan, for example, as early as 2004, PCB related application materials industry output value has reached 452.7 t. Its output value accounted for 35.8% of the whole Taiwan electronic material industry output value, the Taiwan electronic materials six industry's biggest production industry. As for the materials in PCB industry output value, but also created the excellent grades. Including electronic grade fiberglass cloth, flexible copper clad and IC loading board (PCB) production in the global top three.
The growth of the relevant market and trends
But since last year, PC upstream raw materials for the growth of the international copper prices rose sharply, and application products, copper foil substrates and other products of upstream raw materials in the scene of a rising price, increased shipments in 2006 Taiwan PCB material market scale has reached nt $77.7 billion, compared with 2005 increased by nearly 21%.
In 2007, because of the copper foil, glass fiber yarn/fabric and so on raw material price rise of stabilizing the property, the base board factory sharply raise prices will reduce, vendors and also to have the more competitive price, although in the first quarter of 2007 belongs to the traditional off-season, but under the help of consumer product demand growth, in the first quarter of PCB output grew 7% from a year earlier, as for in terms of soft PCB, because mobile phone product growth is slowing, LCD with soft plate prices, increase by about 1%, only in respect of IC loading board, because is still in the oversupply situation, growth rate of about 2%.
Rising in recent years due to the green environmental protection idea, the pursuit of environmental protection has become one of development trends on raw materials, for example, Japan JPCA show there are quite a lot of environmental resources recycling technology, and in general the development of technology, the pursuit of high frequency, high heat resistance and high performance, is also the PCB maker direction, due to the light of consumer products to pursue volume, in the material and the PCB itself also will be one of the important trend of light-weight development.
The application of material development
Hard board pcb
In general on the board and PCB manufacturing, the change of the material is not actually big, basically all is by the copper foil substrates (CCL), copper foil, film, and of all kinds of chemical products, in terms of proportion of raw materials costs, with copper foil substrate of the highest cost, as the number of layers of different, from about 50% to about 70%. The main composition of copper foil substrate material is glass fiber cloth and electrolytic copper foil. The function of the glass fiber cloth is reinforcing hardness, its material is made of glass fiber yarn with flat weave. Taiwan PCB industry has more than 30 years, in the middle and lower reaches of the industrial structure is complete, Taiwan manufacturers in the field of glass fiber yarn and glass fiber cloth cultivated for a long time, the current has been dominant position in the global industry. Electrolytic copper foil as one of the base material of the electronic industry, because of the copper foil substrate is the essential material of PCB, so high in terms of quality, not only requires heat resistance, oxidation resistance, and that no pinhole on the surface of the requirements, wrinkles, and laminated sheet should have high peel strength, and must use general etching method form printed circuit, no processing and substrate pollution phenomena, such as particle migration, belongs to the technical level of the higher copper processing materials.
As for copper foil substrate is the most important key of PCB, on its classification, by using different raw materials and flame resistant properties to distinguish, in the use of raw materials, according to plate reinforced material is different, can be divided into: base paper, glass fiber cloth, composite base (CEM), laminated sandwich plate and special materials (ceramics, metal core, etc.) the five classes. According to the different substrates using the resin adhesives, common paper-based (insulating paper as reinforcing material) CCI, with phenolic resin (XPc, XxxPC, FR - 1, FR - 2, etc.), epoxy resin (FE - 3), polyester resin and other types.In respect of glass fiber cloth, the most widely used belong to epoxy resin, FR (FR - 4-5), and other special resin (with glass fiber cloth, polyethylene base? In order to increase the material such as amine fiber and nonwoven fabric) of the substrate type, the special resin contains: double horse? Imine modified three? Resin (BT), get together? Imide resin (PI), diphenylene ether resin (PPO), maleic anhydride imide - styrene resin (MS), poly (cyanate ester resin, polyolefin resin, etc.
More complicated, due to the current electronic products function and performance requirements also more and more high frequency, PCB in order to conform to the requirements of the above, we also can give attention to both the product size, so almost all profes sional direction development, therefore based on the copper foil substrate is the mainstream of fiberglass cloth.
And in accordance with resistance to natural features to distinguish words, basically can be divided into flame retardant (UL94 VO, UL94 V1) and non flame retardant (UL94 HB level) two types of substrates. In recent years, with the increased attention given to the environmental protection question, and separated in the flame retardant CCL 1 new type does not contain bromine class of CCL varieties, and can be referred to as the "green flame retardant CCL". With the rapid development of electronics technology, the cCL have higher performance requirements. From the performance of the CCL classification, therefore, is divided into general performance CCL CCL, low dielectric constant, high heat resistance of CCL (general plate L at above 150 ℃), low thermal expansion coefficient of CCL (generally used to encapsulate the substrate), and other types.
Softness pcb
As early as 1960 to 1960 s last century, flexible printed circuit board is widely used in automobile and photographic industry, began his role is only one cable and substitute the function of winding, technology level is low, in the 1980 s when the range of application technology level up gradually, products applied to telecommunication products and military products, some even has begun to into the use of automation technology. And after the 90 s, flexible circuit board with the coming of information age, the emphasis on high function, small volume and light weight under the requirements of a new purposes, such as portable mobile devices and laptops and other products. In addition, the LCD panel COF package technology and IC structure loading plate is also one of the main application of flexible printed circuit board.
Soft PCB flexible printed circuit board (FPC) (FPC) consists of insulating base material, adhesives and copper conductor, because its body is made up of insulating base material, adhesives and copper conductor, because of its flexible and so can be called flexible printed circuit board. The characteristics of flexible printed circuit board for stereo wiring, can cooperate with equipment are embedded in the shape of the free after processing of the conductor, and generally with stereo wiring, can cooperate with equipment are embedded in the shape of the free after processing of the conductor, and general rigid laminated board cannot reach flexible, light and thin, and so on characteristics. In general, can be divided into the single side, double side, multi-layer soft PCB and soft hard mixed products.
In single soft PCB material applications, since there is only a conductor layer, layer dispensable. The materials, the insulation of the basement with varying according to the application of the product. General common insulating materials with polyester, polyethylene imine, ptfe, soft - epoxy glass fiber cloth, etc. And double soft PCB is conductor will increase two floors. As for multilayer soft PCB, with multiple layers of pressure technology, can be more than three or four layers of structure, and multi-layer soft PCB according to its flexible, can be generalized into three kinds. As for mixed PCB, is combined with soft PCB with hard board PCB, soft PCB are laminated in multilayer board PCB internal, to reduce the weight and volume, and has a high reliability, high packing density and excellent electrical properties, etc. Characteristics.
In order to achieve the type with the miniaturization of electronic products, in addition to the PCB need to further advance the high-density wiring, in recent years on the PCB forms have appeared in the plane of the component to be used by the original 2 d installation board PCB substrate, turned on the three-dimensional 3 d for the installation of multiaxial characteristic, adopt flexible soft substrate (FPC) in the direction of the transformation, such components and substrate would be narrowed in the internal space of the product. 3 d installation and soft PCB board and multilayer PCB by combined the technology of hard - flexible substrate, won a large number of applications quickly and in recent years.
The challenge of green technology
Because of the green wave wave, plus the European Union RoHS standard, lead-free technology on PCB actually has caused considerable impact, some PCB (especially for large complex thick boards) according to the properties of the laminated material, may be due to the lead-free soldering temperature is higher, and cause, Cu crack, delamination, laminated burst failure such as CAF transmission (anode) must be increased failure rate. PCB surface coating material has great influence. Observed on the actual application of the general, welding and Ni layer (from ENIG coating) between the joint than welding and Cu (e.g., OSP and immersion silver) between the joint are more likely to rupture, which also indirectly caused the similar to Microsoft's Xbox 360 comprehensive failure phenomenon, the design of electronic products will pay more attention to avoid this kind of problem again. Especially under the mechanical impact, such as drop test, the general will occur more PCB lead-free soldering is broken, and PCB industry will inevitably face the trend with the challenge of the green process, so the material application on the design concept of it must be more breakthrough.
Last year, thanks to a rise in copper prices lead to PCB industry cost pressures intensify, although this year has been slow, but the resulting crude oil prices rising gradually, PCB material again this year the price rise pressure, its gain degrees are beyond the scope of PCB manufacturers can absorb, and because the Taiwan on key materials obtained often restricted to foreign suppliers, therefore, will inevitably be affected in the competitive, in the face of other competition, such as China, Japan, South Korea and other countries, formed the Taiwan PCB factory concern.
