Printed circuit board (PCB) has become an indispensable part of modern electronic equipment. Whether it is high-end electronic equipment from the sky or the sea, or household appliances and electronic toys, PCB is loaded with electronic components and electrical signals, and PCB develops along with the development of the entire electronic information industry.
The innovation of printed circuit first lies in the innovation of PCB product and market.The earliest PCB products were single panels, with just one layer of conductor on the insulation board, and circuit width measured in millimeters, which were used commercially in semiconductor (transistor) radios.Later, with the advent of television, computer and other products, PCB products were innovated with the appearance of double-panel, multi-layer board, insulation board with two or multi-layer conductors, and the line width was gradually reduced.In order to adapt to the miniaturization and lightweight development of electronic equipment, flexible PCB and rigid-flexible PCB have appeared.
Now, the main market of PCB is in the fields of computer (computer and peripheral equipment), communication equipment (base station and handheld terminal, etc.), household electronics (TV, camera, game machine, etc.) and automobile electronics, PCB products are mainly multi-layer board and high density interconnection (HDI) board.Along with the computer to the high-speed and large capacity, the mobile phone to the multifunctional intelligent, TV to high-definition 3 d, cars to develop in the direction of high security intelligence, HDI PCB also shift from wire connection to electronic circuit function, namely the PCB products in addition to the basic of conductor line, also includes passive components such as resistors, capacitors and active components such as IC chip.The new generation HDI PCB is embedded component PCB with internal components.The updated PCB board is suitable for high frequency and high speed signal transmission applications. The PCB layer will contain optical fiber and waveguide, forming a photoelectric PCB board suitable for transmission of signals over 40GHz.
It is because of the continuous innovation of PCB products that we have ushered in the spring of the development of printed circuits.Smart phones will bring the high tide of embedded component printed boards, LED energy-saving lighting will bring the high tide of metal based printed boards, e-books and thin-film displays will bring the high tide of flexible circuit boards.
The innovation of printed circuit is based on technological innovation.The traditional technique of PCB manufacturing is copper foil etching (subtracting method). By etching copper foil insulated substrate by chemical solution, the unwanted copper layer is removed and the required copper conductor is left to form the circuit diagram.Interlayer interconnection between double-sided and multi-layered plates is achieved by drilling and electroplating copper.At present, this traditional process is difficult to adapt to the production of micron thin line HDI boards, to achieve rapid and low-cost production, to achieve the goal of energy conservation, emission reduction and green production. Only technological innovation can change this situation.
High density is the eternal theme of PCB technology.Higher density is characterized by thinner lines, smaller interconnections, higher Numbers and thinner.For example, the conventional capacity of line width/line distance of PCB has been refined from 100 bucks m to 75 bucks m and 50 bucks m, and it will be refined to 25 bucks m and 20 bucks m in a few years. Therefore, innovation of copper foil etching process is necessary.
For the technical innovation of printed circuit, people have been pursuing semi-addition method and addition method, that is, to deposit copper layer in insulating substrate to form circuit diagram, which is an improvement of traditional subtraction method. Although there is progress, it still needs a lot of energy consumption, and the cost is also higher.The new innovation path is printed electronic circuit (PEC), which has brought revolutionary changes to PCB products and production process.The printed electronic circuit technology adopts the pure printing method to realize the electronic circuit diagram, namely USES the screen printing or the offset printing or the inkjet printing process, prints the functional ink (the conductive ink, the semiconductor ink, the insulation ink, etc.) on the insulation base material, obtains the required electronic circuit.This technology can simplify the production process, save raw materials, reduce pollution and reduce production cost. If equipped with Roll to Roll processing equipment, it can achieve mass production and low cost.
The development of printed electronic circuit technology will bring the PCB industry to a higher level.