inkjet technology in the field of application of printed circuit boards
Printed circuit board (PCB) initially started making process is to print circuit board type, but later because the resolution requirements for line increase, while the printing process can not meet, so the lines changed to high-resolution photolithography process replaced. However, the improvement of printing technology in recent years, some advanced printing such as ink-jet (InkJetPrinting), Screen Printing (ScreenPrinting), offset printing (FlexographyPrinting) and printed (GravurePrinting), the resolution can be printed line by the hundreds of um upgraded to make use of printing for hundreds of um line of production regained. Repeatedly stressed in recent years, green printing process is another try for the reasons discussed widely, because the use of printing can reduce the circuit production process of waste materials, and process steps can be reduced to save energy and reduce waste. Printing technology has the following advantages.
1.PCB Manufacturing process steps to reduce: the circuit board can be made on line photoresist, exposure, development, etching and resist stripping steps reduced, replaced by printed photoresist, conductor lines and insulating material on the substrate, eliminating the negatives and the use of work mask.
2. Material use reduction: to reduce photoresist, developer, etching and stripping liquid film former such as the use of chemicals, but also exempt from the process waste and waste treatment.
3. Conversion process is easy: You can directly digitized by the computer directly to the line to be printed on the substrate, no longer prepared to meet the different product set and the mold and light equipment.
4. Thinning line: yellow line process of PCB manufacturing capacity of L / S = 3mil/3mil, R & D capabilities to 2mil/2mil, if the printed circuit materials and equipment with good resolution can be achieved 1mil/1mil.
5. Low-cost process: to reduce photoresist, developer, etching and stripping liquid film former such as the use of chemicals, reduce material costs, because the process steps also reduce the use of space can also increase plant flexibility.
PCB ink-jet technology to create an instance as an example when the EPSON, EPSON original use of inkjet technology improvements, there are CBIT (CircuitBoardInnovationbyInkJetTechnology), through its production of inkjet machine with metal conductors and insulating material on the PI to ten laminates, selected as the basis for the first target COF.
Second, market overview
Inkjet technology used in production lines to the success of PCB production line, impact factor were the process, cost, materials were observed.
Process: continuous inkjet technology is still in development, PCB is the need to quickly produce a large number of industries, so the production speed and ink-jet technology can yield the same process with the existing yellow, or would affect the possibility of better replace the yellow light coming into the mainstream of the reasons for the process.
Cost: As inkjet technology is still evolving, the current cost of materials and equipment are quite high, so the cost of materials and equipment are high, the future can be reduced by how much will that affect its ability to enter the mainstream market reasons one.
Material: Conductive inks can achieve a good match with the equipment, including viscosity / flow and molecular weight, will not block the inkjet head, conductive nano-metal conductor ink formulation, the material has been commercialized Ag using silver-based materials because the oxidation of copper is also necessary to overcome the problem. But silver is precious metals, high prices, can reduce the cost or the development of nano copper conductive paste will be the focus.
Because the material is made from metal powder slurry, after the inkjet line to go through sintering, but also because of other substances mixed with the metal powder slurry evenly distributed, so that the sintered conductor lines have a problem with impedance Therefore, the line too small electrical conduction problems arise, it is also for this reason can only be used in the early fine lines generally did not focus on home appliances with a single / double panel based.
Because all of these restrictions, PCB manufacturer discourage the use of inkjet technology, but also to the development of inkjet technology in the market, highly opaque information, blocking the interest of inkjet technology vendors want to try put, it is expected in 2012, IEK Only a few companies before using inkjet technology used in the PCB, screen printing, photoresist, and to mark the PCB on the other components of the position. Fabricated using inkjet technology for research and development and only limited prototype production, and the successful development of very few manufacturers really want to be able to IJP conductive lines for the production of products to line width from 70um ~ 100um single, Soft-sided main board and hard board, more than 100um line products will consider the cost of screen printing technology for production, so inkjet technology to manufacture PCB market growth is rather slow. Estimated 2012 global use of inkjet technology used in the production of conductive circuit board on the market size could reach 0.09 million, in 2013 the market size could reach 0.5 million, in Figure 1. 2012? Most of the companies is only just to test products, not mass production. 2013 on the circuit board industry, inkjet technology is still only a trial of new technology, can have a chance in 2013 after a wide circuit board into the application, still need to rely on material properties, material and equipment costs and the head of the able to produce and set the line width.
Third, the investment element of inkjet line substrate
PCB manufacturer are willing to ink-jet technology for PCB production, business strategies need to account for the firm, and the ink-jet technology itself material, equipment development.
1. Trading Strategies
PCB manufacturer themselves will affect the type of products is suitable for the production line into inkjet technology, inkjet is currently the conductor line production line, is still not mature enough so that no mass production within the next five years if production can also to apply the low-rise, line width, conductor impedance of less stringent requirements on the product, so the more the early stages of commercialization opportunities in single and double panels and RFID substrate, due to broad lines of these products, the impedance of the line requirements are less stringent than the chance to get into.
Compared to the inkjet line substrate exposure, developing and etching process produced the speed of the line is still much slower, so a lot of emphasis on rapid production of PCB industry for the use of inkjet technology than those without incentives, but is the product diversification, multi-batch production businesses have greater incentive to use inkjet technology. Long-term observation of inkjet line technology can indeed reduce the waste in the PCB manufacturing process to achieve the purpose of environmental protection and energy saving, environmental protection if the PCB manufacturer for the import process has urgent needs, consider using inkjet technology line of products in the circuit requires less on The Fine Line is still based on the use of existing process-based.
2. Materials Development
Can inkjet line substrate is the most important commercial materials and equipment with the development phase. Including the use of nano materials mixed slurry of metal powder, metal powder particles can not be too large to avoid clogging the nozzle device, in addition to the slurry as a line of metal powders after sintering at high temperature was needed to achieve a good conductive properties, so consider the characteristics of the substrate itself, metallic powder, the following sub-40nm to be met before to a temperature below 200 ℃ sintering, which also Caishi are able to withstand the temperature of the substrate.
Currently used in nano-silver metal powder slurry-based, so the cost of precious metals, but silver is relatively high, as currently used in the production of nano-copper lines, it is because copper is difficult to overcome the problem of easily oxidized, so there is no use of copper metal powder slurry to the material.
3. Equipment development and investment
Inkjet line of equipment currently still developing the plant, many are still laboratory equipment, or after the sale to sign confidentiality agreements must not be disclosed. Japanese equipment manufacturers considered to be fairly early into development, laden with materials and equipment advantage of Japan to jointly develop, the current line equipment, ink jet machine according to the size of about 600 in the NT between 1000 million. Maturity of the current equipment, as well as close coordination with the extent of material suppliers, equipment manufacturers use a home use with the materials necessary to avoid the inkjet head injury, so the present material, whether exclusive or acquisition costs are high, short-term costs are difficult to reduce.