The printed circuit board manufacturing process makes it possible to create complex electronic circuits using a fairly simple technique. The process is sometimes called PCB production, and it includes four main steps. These steps include designing the circuit and then printing, etching, and finishing the copper clad circuit board.
The design process in the printed circuit board manufacturing can be accomplished by hand, but in manufacturing scenarios it is more likely to be achieved using a form of CAD software to place components in a logical order. The advantage of using software in the design phase of a circuit lies in the fact that errors and omissions are easily noticed and corrected by the designer. In some CAD software, the program is able to detect design errors and offer suggestions. By eliminating design errors during this process, the chances of creating a malfunctioning circuit are greatly diminished.
After the design phase is complete, the circuit is printed to the copper clad circuit board in a process called patterning. In essence, patterning creates a stencil layout on the surface of the board. The ink used to create this stencil layout is resistant to the corrosive etchant solutions used to etch the board. Once printed, the areas of the circuit board which are covered by ink will not be affected by the action of the etchant solution. There is one caveat to this statement, however. If a printed circuit board is left in the solution for an extended period of time, the corrosive acid may eat away at the sides of the protected areas creating what is called a thin trace.
The next step in the printed circuit board manufacturing process is etching. The printed board is immersed in an etchant solution, which is usually composed of muriatic acid and hydrogen peroxide. The acid dissolves the unprotected copper leaving only the printed circuit intact. The lines of this printed circuit material are called traces.
The printed circuit board manufacturing process is finished by washing the board in a neutralizing bath of water to remove any traces of etchant that may remain. The board is then drilled in the appropriate spots to receive components, such as resistors, transistors, and diodes. In some cases, the printed circuit boards are left undrilled for later use. This is common among electrical hobby shops that use the printed circuit board manufacturing process to create and sell kits to electronics hobbyists.