Printed Circuit Boards (PCB) are fascinating things. Every day, we have the honor and good fortune of fabricating printed circuit boards that go into everything from personal electronics to airplanes, and robots to research projects. It's both a privilege and a responsibility to deliver top quality manufacturing for these projects. There are several unique steps in the PCB manufacturing process. This circuit board manufacturing overview will walk you through our PCB manufacturing process step-by-step.
Steps in PCB Circuit Board Manufacturing
Step 1: Film Generation
Layer Films are made from photographically exposed mylar. We generate these films from your design files, creating an exact film representation of your design. We create one film per layer. When Gerber files are submitted, each individual Gerber file represents one layer.
Step 2: Shear Raw Material
Industry standard 0.059" thick, copper clad, two sides. Panels will be sheared to accommodate many boards.
Step 3: Drill Holes
Through holes required for your PCB design are created, using NC machines and carbide drill bits.
Step 4: Electroless Copper
For holes that require a conductive copper layer inside the hole (to electrically connect the two sides of the printed circuit, we apply a thin copper deposit in hole barrels.
Step 5: Apply Dryfilm and Image
To start placing circuit board routing features on the board surface, we start by applying photosensitive dryfilm (plate resist) to the panel, covering the entire board area. Then the film image from step 1 is placed over the board, and a light source expose the uncovered portion of dryfilm. Then we develop the board.
Step 6: Pattern Plate
This step is an electrochemical process which builds copper into the holes and on the trace area. Here we apply tin to the surface.
Step 7: Strip & Etch
In this step, we remove the dryfilm, then etch the exposed copper. The tin protects the copper circuitry from being etched. At this point, the fundamental circuitry of the board is completed.
Step 8: Solder Mask
Next we apply solder mask area to entire board, with the exception of solder pads. Solder mask prevents solder from accidentally shorting out any other parts of the printed circuit board. Later, when assembling the boards by attaching components, the solder should only adhere to designated solder pads.
Step 9: Solder Coat
Apply solder to pads by immersing into tank of solder. Hot air knives level the solder when removed from the tank.
Step 10: Nomenclature
Next we apply white letter markings by using a screen printing process.
Last, but not least, we route the perimeter of the board using NC equipment. The board is now complete, and is quickly shipped off to you — our happy customer!