pcb copper foil thickness is generally how much

Copper foil is an anionic electrolytic material, precipitated on the substrate layer of the circuit board a thin, continuous layer of metal foil, which serves as a conductor of electricity for the PCB. It is easily bonded to the insulating layer, receives a printed protective layer, and corrodes to form a circuit pattern. The copper mirror test is a flux corrosion test that uses a vacuum-deposited film on a glass plate.

Copper foil is made of copper plus a certain proportion of other metals beaten, copper foil generally have two kinds of 90 foil and 88 foil, that is, for the copper content of 90% and 88%, the size of 16 * 16cm. copper foil is the most widely used decorative materials.

International PCB copper skin thickness commonly used: 35um, 50um, 70um.

General single and double-sided PCB board copper foil (copper cladding) thickness of about 35um (1.4mil), another specification for the 50um and 70um. multilayer board surface layer thickness is generally 35um = 1oz (1.4mil), the inner layer of 17.5um (0.7mil). 70% of the circuit boards used to complete the thickness of the 35um copper foil, which mainly depends on the purpose of the PCB and signal Voltage, the size of the current; In addition, for the PCB to be over the high current, part of the PCB will be used to 70um copper thickness, 105um copper thickness, and rarely there will be 140um and so on.

Copper thickness is usually expressed in oz (ounces), 1oz refers to 1oz of copper uniformly covered in 1 square foot area of copper thickness, that is, about 1.4mil, it is the weight per unit area to express the average thickness of copper foil. With the formula to express that, 1oz = 28.35g / FT2 (FT2 for square feet, 1 square foot = 0.09290304 square meters).

Different uses, copper thickness is different, ordinary 0.5oz, 1oz, 2oz, mostly used in consumer and communication products. 3oz or more is a thick copper products, mostly used for high current, such as high-voltage products, power supply boards!

Copper thickness (alignment width) will affect the size of the current, although there are already formulas that can directly calculate the maximum current loading capacity of the copper foil, but in the actual design of the line will not be only so simple, so in the design should be fully taken into account the safety of this factor.

Copper Foil Characteristics

Copper foil has a low surface oxygen characteristic and can be attached to various substrates, such as metals, insulation materials, etc. It has a wide temperature range. Mainly used in electromagnetic shielding and anti-static, the conductive copper foil is placed on the backing surface, combined with the metal substrate, has excellent conductivity and provides electromagnetic shielding effect.2 oz copper thickness in mm It can be categorized into: self-adhesive copper foil, double-conducting copper foil, single-conducting copper foil and so on.

Electronic grade copper foil (purity 99.7% or more, thickness 5um-105um) is one of the basic materials of the electronic industry electronic information industry is developing rapidly, the use of electronic grade copper foil is increasing, the products are widely used in industrial calculators, communication equipment, QA equipment, lithium-ion batteries, civilian TV sets, VCRs, CD players, photocopiers, telephones, heating and air conditioning, automotive electronic components, game consoles and so on. components, game consoles, etc.

There is an increasing demand for electronic-grade copper foil, especially high-performance electronic-grade copper foil, in both domestic and overseas markets. According to the forecast of relevant professional organizations, by 2015, the domestic demand for electronic-grade copper foil in China will reach 300,000 tons, and China will become the world's largest PCB and copper foil base**, and the market for electronic-grade copper foil, especially high-performance foil, is promising.

Global supply situation of copper foil

Industrial copper foil can be commonly divided into two categories: calendered copper foil (RA copper foil) and electrolytic copper foil (ED copper foil), of which calendered copper foil has better ductility and other characteristics, and is the copper foil used in the early flexible board process, while electrolytic copper foil has the advantage of lower cost** than calendered copper foil. Since calendered copper foil is an important raw material for flexible boards, the improvement of the characteristics and price changes of calendered copper foil have a certain impact on the flexible board industry.

Since there are fewer manufacturers of calendered copper foil and the technology is in the hands of some manufacturers, customers have less control over the price and supply, so replacing calendered copper foil with electrolytic copper foil is a feasible solution without affecting product performance. However, if the physical properties of the copper foil structure will affect the etching factor in the next few years, in the thin line or thin products, and high frequency products due to telecommunications considerations, the importance of calendered copper foil will be raised again.

There are two major barriers to the production of calendered copper foil, the resource barrier and the technology barrier. Resource barrier means that the production of calendered copper foil needs to be supported by copper raw materials, and the possession of resources is very important. On the other hand, technological barriers discourage newcomers,plated through hole vs via not only in calendering technology, but also in surface treatment or oxidizing technology.

Most of the global manufacturers have many patents and know-how of key technologies, which increase the barriers to entry. If new entrants adopt post-processing production, they are subject to the cost constraints of large manufacturers, and it is not easy for them to join the market successfully. Therefore, the global rolled copper foil market is still a strong monopoly.

Development of copper foil

Copper foil is an important material for copper-clad laminate (CCL) and PCB. In today's rapid development of electronic information industry, electrolytic copper foil is known as the "neural network" for signal and power transmission and communication of electronic products. 2002, China's production value of printed wiring boards has crossed the world's 3rd place, and copper-clad laminates (CCLs), which are the substrate material of PCB, have also become the world's most popular material for the production of printed wiring boards. As a PCB substrate material, copper-clad laminates have also become the world's third largest producer.

As a result, China's electrolytic copper foil industry has made rapid progress in recent years. In order to understand and recognize the past, present and future of the electrolytic copper foil industry in the world and China, experts from the China Epoxy Resin Industry Association (CERIA) have made a review of its development.

From the point of view of the production bureau and market development of electrolytic copper foil industry, its development history can be divided into three major development periods: the period when the United States created the initial world copper foil enterprises and the start of electrolytic copper foil industry; the period when the Japanese copper foil enterprises monopolized the world market in full; and the period when the world multipolarized to compete for the market.