When the copper wire on PCB board is soaked in etching liquid for a long time, it will cause some fine line backing zinc layer to be completely reacted off and separated from the substrate, that is, the copper wire falls off.
The complexity of PCB production process and process maintenance, especially in chemical wet treatment, make it difficult to prevent the surface foaming defects.
Whether gold or silver, the purpose of the process itself is to prevent oxidation, protect the pad, so that it in the subsequent welding process to ensure yield.
The quality of PCB directly affects the quality of the whole electronic products, PCB testing is a timely detection of problems, but also a necessary means to prevent more defective products to reduce losses.
The OSP acts as a barrier between the copper and the air. Simply put, it chemically grows an organic film on a clean, bare copper surface. The only function of this organic film is to ensure that the inner copper foil does not oxidize before welding.
Field observation is a practical investigation method, which is of great reference significance for the internal self-understanding and improvement of PCB manufacturers, as well as the understanding and selection of suppliers.
There are three main types of metal substrate: aluminum substrate, copper substrate, iron substrate. Iron substrate is rarely used in the market, here the focus of analysis is aluminum substrate, copper substrate.
In PCB design, wiring is an important step to complete the product design, it can be said that the previous preparatory work is done for it, in the whole PCB, the wiring design process to limit the highest, the most fine skills, the largest workload.
In order to prevent oxidation of copper layer in PCB board, separate welding and non-welding parts and protect PCB surface, the color of PCB board is also mainly determined by the color of solder resistance paint.
Industrial circuit boards should pay attention to heat dissipation problems; The second is printed board copper foil line, poor quality circuit board power supply line copper foil is very thin, easy to burn due to the current.
Whether in the manufacturing and assembly process or in actual use, PCB to have reliable performance, this is very important.
In short, PCB manufacturing is a complex, long project, need to comply with a lot of rules and regulations, to ensure the normal operation of machinery and equipment, to ensure that improve the work efficiency and yield.
