If you've started the design phase to bring a product idea to life, finding and understanding all of the necessary components can be difficult. This is particularly true if you need to incorporate circuitry of any kind. For those new to the design and development of printed circuit boards, you may not know what kind of process is ahead of you for having them created. Here's a brief look at the development process so that you know what to expect.
The very first step in the process is to create the foundation for the circuit components to sit on. It's usually a fiberglass core, and it'll be crafted to the dimensions and specifications required for your product. This core will serve as the base on which everything else is built.
Copper Foil Addition
Once that fiberglass foundation is crafted, it will be covered in a copper foil. It's a thin foil that's made to be easily manipulated for a precise fit. When that copper foil is cut and shaped, it's time to mark it to show where the traces will go. This is done by creating the PCB design on a thin sheet that is laminated and then applied to the surface. Once that's done, the board is placed under direct UV light where a film is applied for photo treatment. While it's under the light, those traces are etched directly onto the foil sheet.
Once the traces are complete, it's time to get rid of the excess copper foil. This ensures that all that's left behind on the surface of the board is just the copper traces needed for the board design. A chemical bath is the easiest and most efficient method for doing this. The chemicals flush away the residual copper, creating the final copper trace base for the board.
If you're familiar with that green surface color that circuit boards are known for, you might not know that it's the result of a layer of solder mask that's applied to protect the board. The solder mask is applied once the board is cleaned, and it's used to help prevent short circuits.
Bare Board Creation
The rest of the board foundation construction is simple once the solder mask is finished. A silkscreen layer is applied that defines where all of the final components must be placed. This is almost like a color-by-number design that simplifies the last stage of assembly. When the silkscreen is finished, the board is then considered a bare board, because the base is done but it has no actual circuit components placed yet.
In the final stage of assembly, the necessary components are added to complete the circuit board. This includes things like capacitors, resistors, and integrated circuits. When this stage is finished, you'll see a circuit board product like what you're accustomed to seeing inside your electronics.
It's always best to work with an experienced circuit board designer, like one from Streamline Circuits, to ensure that your printed circuit boards are created properly. This reduces the risk of malfunctions in your new product design.