(Photo : Vishnu Mohanan on Unsplash)

If you own an electronic device, it has a PCB or (Printed Circuit Board). The PCB is a small board that helps the gadget to function correctly. It connects the elements so you can use your device for its intended use. 

Even though the circuit board is a small item, the manufacturing process is extensive. To help you understand more about PCB manufacturing below is all you need to know about the PCB manufacturing process.  

Printed circuit boards are usually made with copper. Nevertheless, the manufacturing process is a complex procedure. Even though you will find single, double, and multilayered printed circuit boards, the manufacturing process is the same. 

But due to differences in the board structure, some might require more steps than others. However, it is essential to note that skipping any step may affect the performance of the circuit board. But when all the steps are completed successfully, the board should perform its tasks properly.  

• Substrate - this is the printed circuit board's skeleton. In most cases, it is made of fiberglass. The main reason for using fiberglass is because it provides core strength and helps resist breakage. 

• Copper layer - the copper layer is the circuit board's nervous system. Its work is to carry electronic signals. 

• Solder Mask - the solder mask is the skin of the board. Its work is to protect the copper layer to make sure it does not come into contact with the environment. 

• Silkscreen - this is the last part of the circuit board that shows the logos, part numbers, component reference, symbol switch settings, and test points.  

The manufacturing of a PCB starts from the design to testing. You may need computer guidance and tools to avoid short circuits and ensure accuracy throughout the process. Whether you want to engage a PCB manufacturer or make one yourself, here is how PCBs are made step by step.  

Before manufacturing a printed circuit board, you need to have a design. The design is completed through a computer program. Then you need a particular printer known as a plotted printer. 

The printer creates a film that displays the details of the board. The printed film shows the non-conductive areas and conductive copper traces.  

The substrate is the insulating material that holds the elements of the board on the structure. It is formed by passing the materials through an oven, and then copper is pre-bonded on both sides and etched away to show the design from printed films.  

The next step is printing the design to a laminate. It is known as printing the inner layers. A film created from photo-reactive chemicals that harden when exposed to ultraviolet light is used to cover the structure. 

This is essential because it covers the blueprints and the real print of the board. Also, holes are drilled into the PCB to assist with alignment. 

The next step is to remove the unwanted copper that might have remained on the board. Using a chemical solution that is similar to alkaline solution, the unwanted copper will be eaten away. 

After the alignment, the laminate and resist pass under ultraviolet lights. This helps to harden the photoresist. In addition, the lights reveal the copper pathways. 

Later, the board is washed with an alkaline solution to get rid of any excess photoresist.  

At this step, you will see your printed circuit board taking shape. This is because the layers are fused together. During the lamination process, metal clamps hold the layers together. 

First, a prepreg layer is found on the alignment basin, a substrate layer over the prepreg, a copper foil layer, and more prepreg resin. Then, more copper is applied, that is, the press plate.  

The next step is where holes are drilled into the layers. But drilling is done; you need to use an x-ray machine to locate the drill spots. 

Then, it would help if you had a computer-guided drill to expose the inner panels and the substrate. Also, any remaining copper after this stage is removed.  

Now, your board is ready for plating. Plating is where a chemical solution is used to fuse the layers. Also, the board is thoroughly cleaned using other chemicals. 

Apart from cleaning the board, the chemicals help in coating the panel with a thin copper layer. This seeps into the drilled holes.  

Etching is a vital step in PCB manufacturing. Here, a chemical solution is used to get rid of any unwanted copper under the resist layer. The step helps in establishing the PCBs connections.  

A printed circuit board needs to have information on the board. Therefore, the fabricators must print the date on the board's surface. This process is called the silkscreen application. 

The information on the board includes company ID numbers, warning labels, manufacturer marks, logos, part numbers, and pin locators. 

Once this vital information is printed on the circuit board, generally with an inkjet printer, the surface finish is applied to the board before it is moved to the next step.  

During PCB manufacturing, V-cut is used when panelizing a PCB board. It is a process of CNC milling a V-shaped channel at the top and bottom of the board. This helps in providing solid support.  

Manufacturing of PCBs is an intensive process that involves several steps. Understanding every process's complexity makes it possible to manufacture reliable and effective PCBs. 

After manufacturing, the completed boards must undergo strict testing before being packed. Quality checks and visual inspection are some tests conducted on the board. 

Sign up for our free newsletter for the Latest coverage!