Inkjet Manufacturing Technology for Circuit Boards

Inkjet printing is also called inkjet printing. As a printing process, it can be used for graphic transfer like lithography and screen printing. Inkjet printing is a non-contact physical printing process. It does not need to use chemical potions, and it does not use printing plates or films to print like movable type printing and exposure photography. It only needs to output the printed graphics directly from the computer and control them through the controller. The nozzle of the inkjet system ejects ink particles from the nozzle to form a pattern. The manufacturing process of the traditional PCB circuit is very complicated. It needs to go through the image transfer process, make the metal adhere to the substrate, form the etching manufacturing process of the circuit, and finally appear the desired circuit on the substrate. The current image transfer technology has reached the limit of the line width, and can no longer increase the packaging density. In contrast, using inkjet technology, there is no need to change the production line and prepare components, and only need to directly input the CAD data into the inkjet printing device to achieve the purpose of changing the line. However, the current inkjet technology for printed circuit boards is only limited to a certain step in the numerous manufacturing processes of printed circuit boards, and cannot fundamentally solve the many serious chemical problems of printed circuit board products due to the lengthy process. Pollution, waste gas pollution, high energy consumption and other environmental issues.

1. Technical scheme of full inkjet manufacturing of circuit boards

The full inkjet manufacturing method of the circuit board is to first print the conductive layer, insulating layer, interlayer via hole, solder mask and protective layer on the carrier board according to the computer output graphics, and then print the character layer, components, etc., through layer by layer printing technology, and finally realize the full inkjet manufacturing of the entire circuit board. This technical method can greatly shorten the manufacturing and processing process of printed circuit boards, shorten the original dozens of technological processes to only a few technological processes, and reduce the cost of resources such as production plants, personnel and supporting facilities. Invest in waste. The product processing of this technology does not involve any chemical potion and gas, no waste liquid and waste gas are produced, and meets the national environmental protection requirements. Carbon saving concept. This technical method is also applicable to the processing of metal-based circuit boards, thick copper printed circuit boards, embedded capacitance embedded resistance circuit boards, semiconductor IC substrates and other products, including integrated circuits of various organic and inorganic electronic components, such as electrodes, transistors, etc. , inductors, capacitors, resistors, batteries and other functional components.

2.The technical steps of the full inkjet manufacturing method of the circuit board

(1) According to the layout design requirements of the circuit board, prepare a carrier board with the same size and place it in the inkjet printer;

(2) Input the inner circuit pattern into the inkjet printer through the computer, print the circuit pattern with conductive ink, and print out the non-circuit pattern area with insulating resin ink to manufacture a single-layer inner circuit board;

(3) After the inner circuit board is heat-pressed and leveled, heat-cured or light-cured, repeat steps 1 and 2 to form a multi-layer inner circuit with a conductive layer, a via hole and an insulating layer whose thickness meets the design requirements plate;

(4) Separate the multi-layer inner layer circuit board and the carrier board, and the special function carrier board may not be separated;

(5) Use conductive ink to inkjet print the outer conductive layer pattern of the circuit board on the upper and lower surfaces of the multilayer inner layer circuit board, and perform hot pressing leveling and heat curing or light curing treatment;

(6) Use solder resist ink and protective ink to inkjet print the solder resist pattern and protective pattern on the surface of the outer circuit board, and perform hot pressing leveling and heat curing or light curing treatment;

(7) Use character ink to inkjet print character marking patterns on the surface of the finished circuit board, and perform heat curing or light curing treatment;

(8) Carry out appearance processing on the printed circuit board to form the final multi-layer printed circuit board;

(9) Various other inorganic and organic electronic functional structural materials can also be integrated into circuit boards by this method.

The carrier board in the scheme can be made of paper, metal, glass, ceramic or resin materials, and flexible or rigid materials can be selected according to functional requirements. The inkjet printer can be a common household printer, such as an improved Epson printer. Different types of inks are output according to the colors designed by the computer, and are placed in the corresponding printer cartridges to ensure good printing efficiency. Among them, the conductive ink can use nano-silver or nano-copper and its oxide conductive ink; the insulating ink can use epoxy resin, polyphenylene ether, polyimide, etc. and its modified resin ink; solder resist ink and character ink are both Ordinary epoxy resin-based solder resist and character inks; protective inks are solder paste-based soldering inks. For the hot pressing leveling, a temperature-controlled electric iron can be used for hot pressing leveling of the semi-finished circuit board to ensure a flat and good printing interface. The appearance processing adopts methods such as laser cutting or mechanical cutting. The thickness of the conductive layer is 2-20 μm, the height of the via hole is 5-50 μm, the thickness of the insulating layer is 5-75 μm; the heat curing temperature is 80-200 ° C, and the time is 2-60 min; the light curing type is UV light curing , the curing time is ~30 min; the hot-press leveling temperature is 50~100°C, and the pressure is 1~50 kg.

3. Implementation effect of full inkjet manufacturing of circuit boards

Provide a technical method for full inkjet manufacturing of circuit boards (as shown in Figure 1). This method can not only accurately control graphics, is easy to operate, greatly shortens the circuit board processing process, and does not involve any chemical liquid or gas process, so It is a low-carbon, energy-saving, and environmentally friendly printed circuit board manufacturing process that produces waste liquid and exhaust gas, while greatly reducing the waste of raw materials. It can make printed electronic circuits develop into a brand-new electronic processing process, a brand-new craft technology.

With the continuous research and development of inkjet printing technology, inkjet printing technology has made great breakthroughs and progress. Especially in recent years, major breakthroughs and progresses have been made in inkjet printing machines, inkjet print heads, and inks, such as the super inkjet printing technology developed by the Japan Industrial Technology Research Institute, which can eject ink droplets as small as 1~2 pL device of. There are also UV curable jet printing inks suitable for large-scale production, especially the developed silver-containing nanoscale inks, which provide conditions for the production of PCB products with a line width/spacing as fine as 10-20 μm. In recent years, a more advanced super inkjet printing technology has been developed, the size of the jetted ink droplet can be as small as 1 μm or less, so that a line with a line width of less than 3 μm can be formed.

Summarize

The full inkjet manufacturing technology of circuit boards can easily achieve the purpose of energy saving and emission reduction without using expensive production equipment and environmental protection facilities. This method does not require a mask, and there is almost no "three wastes" in the production process, which improves environmental pollution and realizes green production. This technology can be applied to substrates such as rigid boards and flexible substrates, and can realize highly automated production methods, and multiple nozzles can operate in parallel, thereby increasing production capacity. It can be used in three-dimensional packaging and 3D circuit board manufacturing, and can realize the integration of active and passive functional parts. At the same time, due to the low melting point of metal nanomaterials, the curing temperature of metal lines is as low as 200~300°C. Because of these advantages, inkjet printing technology will be rapidly promoted and applied in the PCB industry, becoming the mainstream of PCB product production, and bringing revolutionary changes and progress to the PCB industry.

The above is the full inkjet manufacturing method of the circuit board introduced by Shenzhen Zuchuang Microelectronics Co., Ltd. for you. If you have software and hardware function development needs for smart electronic products, you can rest assured to entrust them to us. We have rich experience in customized development of electronic products, and can evaluate the development cycle and IC price as soon as possible, and can also calculate PCBA quotations. We are a number of chip agents at home and abroad, including MCU, voice IC, Bluetooth IC and modules, wifi modules. We have hardware design and software development capabilities. Covering circuit design, PCB design, single-chip microcomputer development, software custom development, APP custom development, WeChat official account development, voice recognition technology, Bluetooth wifi development, etc. It can also undertake the research and development of smart electronic products, the design of household appliances, the development of beauty equipment, the development of Internet of Things applications, the design of smart home solutions, the development of TWS solutions, the development of Bluetooth audio, the development of children's toys, and the development of electronic education products.