The PCB fabrication process is an essential element of the electronics production lifecycle. PCB fabrication employs many new areas of technology that have led to significant improvements in reducing the size of the components and rails used and the reliability of the board.
Producing a PCB is a complex process that involves many steps. Here, we will introduce you to the entire PCB fabrication process of our factory. It has 20 steps. This ultimate guide covers the most important steps in the production of PCBs.
We guarantee and ensure that our products meet our promises through more stringent product specifications and quality controls than other suppliers.
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Among the key subjects on PCB Fabrication Process include:
PCB Design and Layout:
This section outlines the precautions for PCB layout, precautions before PCB fabrication, and an introduction to pre-production engineering.
This section briefly describes the production preparation process, including:
Cutting and laminating according to the size of the finished board or the size of the panel;
The primary purpose of drying is to remove the moisture in the board and prevent it from warping during processing. Generally, it dried at 150℃ for 3-4 hours.
Inner Layer Imaging:
This section briefly describes the Inner Layer Imaging consisting of three steps: Inner Film, Inner Exposure, and Inner Layer Development.
Inner Layer Etching:
This section briefly describes the Inner Layer Etching consisting of two steps of etching and unloading the film.
Through the etching line, the copper skin covered by the dry film protects, while the copper skin not protected by the dry film is etched away.
The line pattern that needs to retain at this time will display by etching.
Unloading the film
Retreat the dry movie of the copper sheet on the core board, and the line pattern to retained is finally forme.
Inner Layer AOI:
This section briefly describes Inner Layer AOI is an automatic optical inspection,
To check whether the core plate after etching has an open or short circuit,
And the print is clean or not.
This section mainly introduces the definition of Lamination.
This section introduces mostly Drilling.
Electroless copper deposition:
This section describes the copper primarily in the base plate. Through the chemical reaction, the hole is coated with a skinny layer of copper, about 2-3 um.
Horizontal Electrolytic Plating:
This section focuses on the copper in the base plate, and the copper in the hole can be thickened to 5-8um by electron transfer reaction.
Outer Layer Imaging:
This section focuses on three aspects of outer imaging:
- Outer Layer Film
- Outward Layer Exposure
- External layer development
This section focuses on the three levels of Graphic Plating, which consists of thick copper plating, tin plating, and film removal.
Outer Layer Etching:
This section mainly describes the composition of Outer Layer Etching.
Coat the entire panel with a liquid solder mask. The board is then exposed to high-intensity UV light. Solder mask is applied to achieve the following: Protect copper circuitry from oxidation, damage, and corrosion.
WellPCB prints the solder mask under customers’ requirements and do not have an extra charge.
Silk screening is a vital step since this process is what prints important information onto the board. Then PCB finally passes onto the coating and surface finishing process.
This step is to enable protection of the surface and good solderability. Common surface finishes include such as Electroless Nickel Immersion Gold, Hot Air Solder Leveling(HASL), Lead-Free HASL, Immersion Silver, OSP( anti-oxidation), etc.
Following the implementation of the Rohs directive in the EU, all products containing lead and bromine will not be allowed to enter the EU market; therefore, the traditional pewter process will be gradually replaced.
WellPCB defaults to the lead-free HASL for our customers If you need any other way to deal with it, please check the box when you place the order.
The engineering department creates a shape program based on the border provided by the customer.
The shaping process is based on the engineering department to provide milling
Other Surface Finishing Process:
This section focuses on the two methods of the Other Surface Finishing Process：V-CUT、Gold Finger.
So far, board production has been basically completed, but another important thing is to conduct electrical testing to ensure functionality. The main tests that are performed are circuit continuity and isolation tests.
Basic electrical reliability testing, used for checking the integrity of the tracks and the through-hole interconnections-checking to ensure there are no open circuits or no short circuits on the finished board. WellPCB using Flying Probe Testing， which depends on moving probes to test the electrical performance of each net on a bare circuit board. We check each net to ensure that it is complete (no open circuits) and does not short to any other loss, to ensure optimum performance and quality.
Final Visual Inspection (FQA, FQC):
This is the final step in the PCB fabrication process. The professional quality control team will perform the final inspection of each PCB. Including visual inspection, finished product size inspection, aperture hole number measurement, warpage measurement, etc. If the inspection is qualified, we will print a test report for customer reference.
This section describes mostly the PCB packaging method and delivery time.
After inspection, the PCBs are vacuum-sealed to keep out dirt and moisture. WellPCB suggests DHL and FEDEX which are more convenient and fast – generally 1-4 Days so you can receive the board as soon as possible and start your project soon.
I believe that you have a general understanding of the fabrication process of PCB after reading this guide.
If you are ready with your PCB design and want to try to implement it for your project; try using our quotation system and upload your CAD or Gerber files. And our experienced professionals are available for consultation and to advise you when needed.