PCBA is the abbreviation of Printed Circuit Board Assembly in English, that is to say, the PCB empty board goes through the SMT upper part or the whole manufacturing process of the DIP plug-in, referred to as PCBA. This is a common way of writing in China, while in Europe and the United States, the standard writing method is PCB'A, with the addition of "'", which is called an official idiom.

The substrate of PCBA is generally classified according to the insulation part of the substrate, and the common raw materials are bakelite, fiberglass board, and all kinds of plastic boards. PCB manufacturers generally use an insulating part made of glass fiber, non-woven materials, and resin, which is then pressed into "adhesive sheets" with epoxy resin and copper foil. The metal coating is not only the wiring on the substrate, but also the place where the substrate circuit is welded with the electronic components. In addition, different metals also have different prices, different will directly affect the cost of production; different metals also have different weldability, contact, but also have different resistance values, which will directly affect the efficiency of components. Commonly used metal coatings are: copper and tin.

The design of the printed circuit board is based on the electronic circuit diagram to achieve the functions needed by the circuit users. The design of printed circuit board mainly refers to layout design, which requires internal electronic components, metal wiring, through-hole and external connection layout, electromagnetic protection, heat dissipation, crosstalk and other factors. Excellent circuit design can save production cost and achieve good circuit performance and heat dissipation performance. Add-layer printed circuit boards have been widely used. Until now, it is important to develop a robust testing strategy for large, high-density PCBA to ensure compliance and function with the design. In manufacturing processes, especially in testing, the increasing complexity and density of PCBA is not a new problem. The quality of the manufacturing process is evaluated to the whole PCBA, and the combination of traditional ICT and X-ray delamination is a feasible solution.