If you think the manufacturing of your PCB board is complex, you are only partly correct. Although it does require an expert to make sure the board is manufactured correctly, these companies know just what they’re doing and, therefore, promise professional results every time. It is natural to wonder, what is PCB manufacturing, so below is a step-by-step explanation of just what goes on during the manufacturing process.
Design/Output and More
Naturally, the design of your PCB board is going to be the first step in making sure the board is manufactured properly. When it comes to the board’s design and output, several computer software programs are available that make the task super easy. Most designers will then forward their PCB file to the board houses for production.
After a design for manufacture (DFM) check is completed, a special printer called a plotter is used that makes photo films of the PCB boards so that circuit boards can be printed. Plotters are highly sophisticated laser printers that provide a very detailed film of the board’s design. When they’re done, a plastic sheet is made that shows a photo negative of the PCB board in black ink. The black represents the conductive copper parts of the board, and the clear portion represents everything else.
Each layer will get its own black-and-clear sheet, and holes are usually punched so that each film is perfectly aligned. The next step involves printing the figure on the film onto the second layer, which is copper foil. The board is thoroughly cleaned at this point, and it receives some UV light so the film and board line up correctly. After it is washed again, unwanted copper is removed and the layers are lined up properly. An optical inspection is also conducted at this time.
When the manufacturers get to this point, the board starts to take shape and the different layers are ready to be lined up correctly. This is done in a two-step process, layering-up and bonding, then holes are drilled into the stack board. Up to this point, the layers have been molded together so the drilling part is fairly simple. A chemical bath is given to the board, then a thin layer of copper is applied, which fills in the holes on the board.
Next comes a few steps that are repeated; namely, imaging of the outer layer and more plating, followed by a final etching, all of which help the connections and the conducting areas establish themselves properly. The solder mask is applied to both sides of the board, a surface finish is applied, and the silkscreen is applied. Finally, a series of tests is conducted to make sure everything is working the way it should.
So, what is PCB manufacturing? As you can see, it involves numerous steps, and the steps mentioned above can change slightly depending on the manufacturer. The main thing to remember about the manufacturing of PCB boards is that it is a technique that requires each and every step be done to perfection, because this is the only way to make sure the final product is one the customer will be happy to receive.