Basic knowledge of PCB circuit board copper foil
I. Introduction to Copper Foil
FoilCopper foil (copper foil): a type of feminine electrolytic material, a thin, continuous metal foil deposited on the substrate of the circuit board, which acts as a conductor of the PCB. It easily adheres to the insulating layer, accepts a printed protective layer, and forms a circuit pattern after corrosion. Copper mirror test: A flux corrosion test using a vacuum deposition film on a glass plate.
Copper foil is made of copper plus a certain proportion of other metals. There are two types of copper foil: 90 foil and 88 foil. That is, the copper content is 90% and 88%, and the size is 16 * 16cm. Copper foil is the most widely used decorative material. Such as: hotels, temples, Buddha statues, golden signs, tile mosaics, crafts, etc.
Copper foil has low surface oxygen characteristics, can be attached to a variety of different substrates, such as metals, insulation materials, etc., has a wide temperature range. It is mainly used in electromagnetic shielding and antistatic. The conductive copper foil is placed on the substrate surface, combined with the metal substrate, has excellent conductivity and provides the effect of electromagnetic shielding. Can be divided into: self-adhesive copper foil, double-conductor copper foil, single-conductor copper foil, etc.
Electronic grade copper foil (more than 99.7% purity, thickness 5um-105um) is one of the basic materials of the electronics industry. The electronic information industry is developing rapidly. The use of electronic grade copper foil is increasing. Products are widely used in industrial calculators, Communication equipment, QA equipment, lithium-ion batteries, civilian televisions, video recorders, CD players, copiers, telephones, heating and cooling air-conditioning, automotive electronic components, game consoles, etc. The demand for electronic-grade copper foil, especially for high-performance electronic-grade copper foil, is increasing in domestic and foreign markets. Relevant professional organizations predict that by 2015, China's domestic demand for electronic-grade copper foil will reach 300,000 tons. China will become the world's largest manufacturing base for printed circuit boards and copper foil bases. The market for electronic-grade copper foils, especially high-performance foils, is promising. .
Third, the global supply of copper foil
Industrial copper foil can be generally divided into two categories: rolled copper foil (RA copper foil) and point-dissolved copper foil (ED copper foil). Among them, rolled copper foil has good ductility and other characteristics, and was used in the early flexible board manufacturing process. Copper foil, while electrolytic copper foil has the advantage of lower manufacturing cost than rolled copper foil. Since rolled copper foil is an important raw material for flexible boards, the improvement of the characteristics and price changes of rolled copper foil has a certain impact on the flexible board industry.
Because there are fewer manufacturers of rolled copper foil, and they are also technically in the hands of some manufacturers, customers have a lower grasp of price and supply. Therefore, electrolytic copper foil can be used instead of rolling without affecting product performance. Copper foil is a viable solution. However, if the physical characteristics of the structure of the copper foil itself will affect the etching factors in the next few years, the importance of rolling the copper foil will increase once again due to the consideration of telecommunications in thinner or thinner products and high-frequency products.
There are two major obstacles to the production of rolled copper foil, resource obstacles and technical obstacles. Resource barriers refer to the need for copper raw materials for the production of rolled copper foil. It is very important to occupy resources. On the other hand, technical obstacles have discouraged more new entrants. In addition to rolling technology, so are surface treatment or oxidation treatment technologies. Most of the major global manufacturers have many technical patents and key technologies, Know How, increasing barriers to entry. If the new entrants post-harvest processing production and are restrained by the cost of large factories, it is not easy to successfully join the market, so the rolled copper foils in the world still belong to a highly exclusive market.
Fourth, the development of copper foil
Copper foil in English is depositedcopperfoil, which is an important material for the manufacture of copper clad laminates (CCL) and printed circuit boards (PCB). In the rapid development of today's electronic information industry, electrolytic copper foil is called: "neural network" for signal and power transmission and communication of electronic products. Since 2002, the production value of China's printed circuit boards has entered the third place in the world. As a substrate material for PCBs, copper-clad boards have also become the third largest producer in the world. As a result, China's electrolytic copper foil industry has developed rapidly in recent years. In order to understand the world, the past, present and future development of China's electrolytic copper foil industry, according to the experts of China Epoxy Resin Industry Association, its development is reviewed.
From the perspective of the production department and market development of the electrolytic copper foil industry, its development history can be divided into three major development periods: the period when the United States created the first world copper foil enterprise and the start of the electrolytic copper foil industry; and Japanese copper foil The period when enterprises are monopolizing the world market; the period when the world is multipolar competing for the market.