The Printed Circuit Boards serve as the foundation of all the major electronics out there. These inventions are found in almost all the computational electronics. These include simpler devices such as calculators, digital clocks, etc. Furthermore, for those uninitiated, the PCB helps in routing electrical signals via electronics. This satisfies the mechanical and electrical circuit requirements of the device. In short, PCBs tell the electricity where to go, bringing your electronics to life.
Furthermore, high speed printed circuit boards usually direct current around its surface via copper pathways network. This complex copper routes system helps in determining the special and unique role of every piece present in the circuit board. The focus of this article will be on the steps involved in high speed pcb manufacturing. Please read on.
Steps in High Speed PCB Manufacturing
First thing before you start high speed PCB manufacturing, you must have a design for the board. The blueprints are what the process will be based on. Generally, you can complete the design process via computer software. Making use of a trace width calculator assists with most details required for the external and inner layers.
Print the Design
There’s a printer – a plotted printer, useful in printing the PCB’s design. Furthermore, it helps in producing a film, which reveals the board’s layers and details. Anytime it is printed, the board’s inside layer will have two ink colors
Creation of the Substrate
This is the time the PCB begins to form. Also, the substrate, which serves as an insulating material (glass fiber and epoxy resin), which holds all the components on that structure, starts to form. This happens by passing materials via an oven. Also, this is where the pre-bonding of copper to the two layer sides takes place. Later, it is etched away in order to reveal the printed films’ design.
Printing of the Inner Layers
Here, you print the design onto a laminate, which is the structure’s body. Furthermore, the photo-sensitive film which is manufactured from the photo-reactive chemicals, which hardens whenever it is exposed onto the resist (ultraviolet light). Also, this helps in aligning the board’s actual print and blueprints. The drilling of the holes in your printed circuit board (PCB) helps with the process of alignment.
Immediately it is aligned, then the laminate and resist goes under the ultraviolet lights in order to harden this photoresist. Furthermore, this light shows the copper pathways. Also, the black ink prevents some areas from hardening that will be taken off later. Furthermore, the circuit board is washed in alkaline solution so as to get rid of excess photoresist.
Getting Rid of Unwanted Copper
This is the time to get rid of all unwanted copper still present on the circuit board. Furthermore, a chemical solution, which is just like an alkaline solution, helps in eating away any unwanted copper. However, the photoresist remains untouched.
Furthermore, this newly-cleaned layer needs proper inspection for alignment. The drilled holes help in aligning the outer and inner layers. Also, a punch machine helps in drilling a pin via the holes. This is to help in ensuring the lining up of layers. Furthermore, once the optical punch is completed, then a different machine helps in inspecting the board. This is just to make sure that no defects are present.
Lamination of the layers
Here, the board takes the right shape as the fusing of the layers together. The metal clamps help in holding the layers altogether as the process of lamination starts. Also, the epoxy resin (prepreg) layer goes to the alignment basin. Furthermore, the substrate layer then goes over that prepreg then the layer of copper foil as well as additional prepreg resin. Then lastly is the application of one more layer of copper, which is called press plate.
Pressing all the layers
The next step in high speed pcb manufacturing is using the mechanical press. This is useful in pressing the layers altogether. Furthermore, the pins are also punched in through all the layers. This is to ensure that they are kept properly secured and aligned. You can remove these pins; this depends on the technology.
Here, the holes are then drilled in the layers using a drill that is computer-guided. This exposes the inner panels as well as the substrate. You remove the copper left once done with this step.
Now, the circuit board is set for plating. This is where a specific chemical solution helps in fusing the layers altogether. Next, is the thorough cleaning of the board by different chemicals. The chemicals also serve in coating the panel using a copper layer. This seeps in the drilled holes.
Imaging of the outer layer
The next step in high speed PCB manufacturing is applying a photoresist layer to the outermost layer before you send it for imaging. The ultraviolet light helps in hardening the photoresist. Here, there is also a removal of all the undesired photoresist.
Here the copper layer is used in plating the panel. Next, the tin guard is then layered onto the circuit board. Why tin is here is to offer some protection for the outside layer’s copper to prevent it from etching off.
The chemical solution used earlier helps in removing unwanted copper present underneath the resist layer. Also, the guard layer helps in protecting the required copper. With etching, it establishes the connections of the PCB.
Application of the Solder Mask
Note that, at this stage of high speed PCB manufacturing, you must clean all the panels before applying your solder mask. You can apply the epoxy using the film of the solder mask film. This solder mask is what gives the PCB its green color.
This is an important step in the high speed pcb manufacturing process. It is so because this is what prints the important information on the board. Immediately you done applying it, the PCB then passes via one final curing and coating.
Here, you plate the PCB using a solderable finish. This depends on the requirements, and it helps in increasing the bond and quality of your solder.
This is the final step of high speed PCB manufacturing. Before you can say that your PCB is complete, you must perform different electrical tests on the board. With testing, you will be able to know if the PCB functions work in line with the initial blueprint designs.
These are the steps necessary for high speed PCB manufacturing. Need more explanations, please inform us.