OSP, PTH, image pre-processing and other processes have Micro-etch this step, what is the difference between them and why? Can provide information on the Javani effect and the principle of the effect of the occurrence of the gold finger in the connection of copper on the circuit, the circuit board through the micro etch tank (SPS+ sulfuric acid series) line will be over the?
Micro-etch is also known as Mild-etch, with Chinese literal translation as "micro etching", which means that micro etching, the general amount of etching is about 20-40microinch, of course, there are lower than or beyond the scope of the case.
In the process of the circuit board, the manufacturer will use different micro etching solution to complete the work. Sodium persulfate solution, sulfuric acid hydrogen peroxide system, organic acid system, super roughening system, will appear in different process. The same potion can appear in different processes, different potions may also appear in the same process. How to use, mainly based on user needs, such as: etching speed, the need for surface roughness, price, process stability, process compatibility, etc.. The detailed data of special chemical systems, suggest you query directly to suppliers, as their general can be formulated in medicine, big companies should have their own experimental data, if not also can seek assistance to medicine suppliers.
Is an electrochemical reaction, mainly refers to the metal surface in the chemical reaction, due to the oxidation-reduction potential difference caused by the acceleration and slow down the role of the reaction. When the active metal is adjacent to the blunt metal, the active metal will accelerate the reaction, and the relative blunt metal reaction will slow down obviously. The greater the difference between the redox potential, the more obvious the effect is.
The area surrounding the gold-plated copper metal etching, there is no way this problem is inhibited, more direct way can line compensation design, line size will be reduced to compensate is more direct and effective way, for reference.