How does pcb led manufacturer develop pcb plating?2021-09-07
International experts in the field of reliability for pcb led manufacturer, through and blind interlayer joints, have talk on long-term reliability. Moreover, it is largely determined that copper is present in holes of pcb led.
In this such conditions, to maintain a proper copper layering some measures can be taken. And there are two possibilities of it. Hence, it is either through copper layer or blind. In both case, materialization proceeding for copper proceedings can be done.
Materialization process in pcb led manufacturer
Materialization process is which forms conductive layering in chip boards. It is present in the holes. This is the main factor on which the purity and accurate composition of pcb led manufacturer is greatly measured. Furthermore, it is a must to have conductive layer in pcb led manufacturer.
Chemical copper plating in pcb led manufacturer
Clearly, over the past several decades, the PCB industry has mainly used chemically deposited copper to make holes conductive. In addition, the work of many researchers is devoted to the study of the mechanism and kinetics of the process of chemical copper plating. Hence, among them, we can mention.
For example, the work . According to the author, copper plating is an electrochemical nature. As, indicated by the strong dependence of plating of copper in surface potential in pcb led manufacturer. For this reason, it is an important step for pcb led processing.
Why is chemical copper plating done?
It happens because, a multitude of micro galvanic couples from two combined stages. Owing to, Cathodic (metal release) and anodic (oxidation of the reducing agent). Apart from this. the speed of the process is controlled by its anode stage.
So, chemical copper plating is always accompanied by hydrogen evolution, the volume of which is equivalent to the amount of deposited copper. Additionally, this indicates a combination of the processes of copper and hydrogen evolution.
Impacts of increased hydrogen electrode potential in PCB, LED
The flow of the latter at potentials in pcb led manufacturer is more positive than the potential of the hydrogen electrode. Thus, in copper plating solutions indicates that the release of hydrogen occurs not by the electrochemical mechanism from water molecules.
Moreover, but is due to the reaction of formaldehyde on the metal surface with the formation of an electrochemically active intermediate substance and atomic hydrogen . Besides, it is the process that involves chemical reactions. In addition, according to the data of this author, the reaction is
CH 2 0 + 20H “- e n>
n> HCOO – + 0.5H 2 + H 2 0.
Furthermore, the total useful reaction in pcb led manufacturer is
Cu 2 + + 2CH 2 0 + 40H – n>
n> Cu + H 2 + 2HC00 – + 2H 2 0.
Reaction for formaldehyde; pcd led manufacturer
Formaldehyde is consumed even during the reaction of its disproportionation (the Cannizaro reaction) – its combined oxidation and reduction. Furthermore, some chemical reactions are involved in this.
Hence the reaction is.
2СН 2 0 + No0Н n>
n> HC00No + CH 3 0H.
Then, this reaction occurs both during the operation of the copper plating baths and during their inactivity. In pcb led manufacturer process of chemical copper plating, the share of formaldehyde consumption for the useful process of copper plating will be more than 90%.
An outlook on CVD technology in pcb led manufacturer
Over the years, CVD technology has evolved continuously, and reliable processes are now available for making PCBs with plated through and blind holes. These processes include the ELHM 200 process.
To show that, the main stages of the ELHM 200 chemical copper plating process and processing modes are shown in Table 1.
Table 1. The main stages of the process of chemical copper plating ELHM 200 and processing modes
|The main stages of the process of chemical copper plating ELHM 200||T process, ^||Processing time, min|
|1.||First, air conditioning ELHM 201||60 … 65||5.6|
|2.||Second, micro-etching ELHM 202||18 … 25||1.2|
|3.||Not only, pre activation ELHM 203||18 … 25||0.5.1|
|4.||But also, ELHM 204 activation in pcb led manufacturer||40 … 45||4.5|
|5.||Finally, chemical copper plating ELHM 205||40 … 45||twenty|
Conditioning by pcb led manufacturer
Conditioner ELHM 201 is a multicomponent system that is a good surface cleaner. At the same time, the composition removes static electric charges, and “loosens” the surface for the most efficient adsorption of palladium in the activation solution.
Microetch operation in pcb led manufacturer
The purpose of this operation is to create a roughness of the copper surface, which will ensure maximum adhesion of subsequent layers. ELHM 202 solution creates a light matte pink, micro-rough surface. Thus, its advantages include a constant etching rate for pcb led manufacturer
Likewise, it, cannot be provided by a classical etching solution based on ammonium persulfate. Certainly, micro-etchant ELKHM 202 does not contain an ammonium group, which, being a complexing agent, when released into wastewater, binds metals into compounds.
Why is operation caried out?
Finally, operation is designed to eliminate the possibility of contamination of the activator. Furthermore, after processing in the pre activation solution, the PP blanks are immediately, without washing, immersed in the activator.
Activation bath purpose in pcb, led manufacturer
The purpose of the activation bath is to create activation centers on the dielectric in the form of palladium metal particles. Indeed, which are the catalyst for the chemical copper plating process. While working on pcb led manufacturer solution of tin-palladium activator, metal concentration of 0.05.. 0.07 g / l is maintained.
Evidently, this low concentration of palladium chloride combined with the stable complex makes the activation solution very stable. Moreover, in 1 liter of ELHM 204B concentrate in the correction mode, ~ 100 m2 of surface can be processed. As a result, periodic heating order of 90 ° C is not required.
Tin hydrolysis and palladium adsorption
After activation during intensive washing of the boards with running water. However, a chemical reaction of tin hydrolysis and adsorption of palladium on the surface of the dielectric take place. Moreover, the use of collection baths for collecting palladium is not recommended.
In addition, the collection tanks, in pcb led manufacturer the medium is rapidly acidified, and the hydrolysis of tin salts begins to slow down. And the catalytic activity of the dielectric surface decreases. For, the advantage of using solution with a low palladium content is also significant saving in precious metal.