Printed circuit boards are the basis of most electronic devices. These wonderful inventions are now found in almost all computing electronics, including such simple devices as digital clocks, calculators, and so on. Printed circuit boards make electronics possible by directing electrical signals using special copper patterns by CAMTECH PCB.
Step 1 – Design
Before proceeding with the development of the PCB, it is necessary to create a board design. Usually, special computer programs are used for this. The designer develops a PCB drawing that satisfies all the specified requirements. The finished design file is then sent to production. To make sure that the design meets all requirements and passes all tests, almost all manufacturers perform a DFM check before manufacturing the board.
Step 2 – Printing the Design
To print PP, a special printer is used – a plotter. With it, we get a film that shows a copper pattern.
After the films are printed, holes are punched through them, which are later used to align the films.
Step 3 – Printing the Inner Layers
The design is printed onto a laminate that serves as the structure for the PCB. Then the laminate panel is covered with a photosensitive film – resist and how
pcb manufacturing make it perfectly.
UV light passes through the translucent parts of the film, causing the photoresist to harden. Hardened Pattern – The copper patterns that will be retained on the final board. In contrast, a dark pattern prevents light from reaching areas that should not be cured so that they can be removed later. The board is then washed with an alkaline solution to remove residual photoresist.
Step 4 – Removing Excess Copper
Now it’s time to remove all unnecessary copper from the PCB. A chemical solution, similar to an alkaline solution, corrodes the excess. The cured photoresist remains intact.
Step 5 – Quality Control
After all the layers are cleaned and prepared, you need to make holes for alignment. According to the holes made earlier, the inner layers are aligned with the outer ones. The piece is placed in a special machine that ensures an exact match so that the holes are punched with microscopic precision.
After that, the board is checked using another machine and defects are detected. From this point on, it will be impossible to correct the missed errors.
Step 6 – Laminating the Layers
At this stage, the layers are bonded together. First comes a layer of epoxy. Then comes a layer of substrate, followed by a layer of copper foil and again epoxy. Finally, another layer of copper is applied.
The PCB is then sent to a laminating press that applies heat and pressure to the layers. The epoxy melts, which together with pressure fuses the layers together.
Step 7 – Drilling Holes
Holes are drilled into the layers with a computer-controlled drill and the underlayment and interior panels are exposed.
Step 8 – Galvanization
The electroplating process uses a chemical to bond the layers together. After thorough cleaning, the printed circuit board is immersed in a range of chemicals. The board is coated with a micron-thick layer of copper, which is deposited over the topmost layer and in the newly drilled holes.
Step 9 – Shaping the Outer Layer
A layer of photoresist is applied to the outer layer, similar to step 3. The photoresist hardens under ultraviolet light. Any unwanted photoresist is removed.
Step 10 – Galvanization
The board is covered with a thin layer of copper, then a thin layer of tin. Tin is designed to protect the copper of the outer layer from etching.
Step 11 – Etching
The same chemical solution that was used earlier removes the unwanted copper underneath the resist layer. A protective layer of tin protects the necessary copper.
Step 12 – Applying the Solder Mask
Before applying the solder mask to both sides of the board, the panels are cleaned and epoxy coated. The boards are emitted by ultraviolet light that passes through the solder mask film. The coated parts do not harden and can be removed later.
Step 13 – Finishing Coat
The boards are plated with gold or silver to provide stronger soldering and further protect the copper.
Step 14 – Silkscreen
On an almost finished board, markings are drawn to indicate all important information using silk-screen printing. The PP finally enters the last stage of coating and curing.
Step 15 – Testing
The technician then performs electrical tests on the board. This process will make sure that the printed circuit board meets all requirements and original templates.
Leave a Reply