How is a circuit board manufactured?

The manufacturing process of a circuit board is complex and precise, involving multiple steps and techniques. This article mainly introduces the primary steps involved in making a bare circuit board.

  • Data Inspection:

Upon receiving the customer’s data, we inspect and optimize it. This inspection ensures the design’s feasibility and allows for further optimization based on our manufacturing capabilities. If there are any issues, we promptly communicate with the customer.

  • Material Cutting:

The necessary raw material, copper-clad laminate, is prepared. The laminate has copper foil covering both sides, with the middle layer typically being fiberglass or epoxy resin. According to the requirements, the cutting machine cuts the laminate to the appropriate size and polishes it.

  • Drilling Process: 

An automatic drilling machine drills holes in the circuit board as per the design requirements, preparing for the subsequent installation and interconnection of components.

  • Chemical Copper Plating:

Chemical copper plating is performed on through-holes and buried vias to make these holes conductive.

  • Dry Film Lamination:

A dry film, which is a photosensitive material particularly sensitive to ultraviolet light, is applied to the copper board. A photomask with the circuit design is then placed over the dry film.

  • Exposure and Development:

Ultraviolet light is used to expose the board, causing the dry film in the circuit areas to polymerize and harden, preventing it from being etched. The development process follows, using a developer solution to dissolve the unexposed dry film, revealing the yellow copper underneath.

  • Etching:

The board is then placed in an etching solution, which dissolves and removes the exposed copper, leaving behind the copper traces covered by the dry film. The remaining dry film is then washed off, leaving the designed circuit.

  • Automated Optical Inspection (AOI):

An automated optical inspection machine checks the circuit board to ensure there are no anomalies before moving on to the next process.

  • Multilayer Board:

For multilayer boards, the produced inner layers are stacked with prepreg (PP) sheets. Copper foil is then placed on both sides of the stack, and the multilayer board is laminated under vacuum and high temperature.

  • Solder Mask Application:

To protect the circuit board from the external environment, a layer of solder mask is applied to the board. The solder mask is removed from solder pads and holes to facilitate the installation of electronic components.

  • Silk Screen Printing:

To prevent exposed copper from rusting, a layer of anti-oxidation material is typically applied. Finally, silk screen printing is performed to add customer-required text and component symbols to the circuit board using white ink.

  • V-Cutting and Cleaning:

The boards are then V-cut for easy separation and thoroughly cleaned.

  • Inspection and Vacuum Packaging:

Finally, the circuit boards undergo inspection and are vacuum packaged.

At this point, the bare circuit board is completed. For more information about the parameters and capabilities of bare circuit boards, please refer to our process capabilities documentation.

0 replies

Leave a Reply

Want to join the discussion?
Feel free to contribute!

Leave a Reply

Your email address will not be published. Required fields are marked *