How to check the parameters of PCB plating

In several ways:

1) Plating time, whether it meets the requirements.

2) Electroplating equipment parameters: such as the size of the current, its change size, voltage, etc.

3) Plating potion, analyze whether the results are within the range.

4) Electroplating operation, whether it meets the requirements.

5) The performance of the electroplating line equipment is regularly evaluated to see if the project is up to standard, such as electroplating uniformity, deep plating capacity value, copper plating adhesion force, etc.

6) Whether there is an abnormal situation in the electroplating production process, and whether the treatment measures given for the abnormal situation are appropriate and appropriate.

7) The quality of the water used in production, whether the water used in each section meets the requirements, whether the ambient temperature and humidity meet the requirements, and whether there is any dripping phenomenon.

In general, the basic idea is to investigate and analyze the major causes of man, machine, matter, law and environment.

The confirmation of electroplating parameters is actually very wide:

1.Plating time, current density.

2.The laboratory test of electroplating solution, the analysis of brightener (generally confirmed with Hastelloy) 3The evaluation of the plating line is mainly to evaluate the uniformity of the plating.

4.The evaluation of electroplating solutions is mainly the uniformity and deep plating ability of electroplating, the ductility of electroplating, and the thermal shock resistance of electroplating copper.

5.The plating line checks the rocking, vibration, gassing, temperature of the solution, liquid level, etc.

Hope it ties you up!

The control parameters of the chemical solution can be checked by chemical analysis.

1. Appearance quality, 2. Thickness of nickel gold layer, 3. Solderability test, 4. Salt spray test test, 5. IR furnace reflow soldering test.

In my opinion, the most likely thing is that the film or ink is in poor contact with the copper surface. This situation may be, 1. The board surface is not cleaned well or is contaminated by oil. 2. The curing of oil or film is not enough.

Electroplating is the process of using the principle of electrolysis to coat a thin layer of other metals or alloys on some metal surfaces, and it is a process that uses electrolysis to attach a layer of metal film to the surface of metal or other materials, so as to prevent metal oxidation (such as rust), improve wear resistance, conductivity, reflectivity, corrosion resistance (copper sulfate, etc.) and enhance aesthetics. Many coins also have electroplated outer layers.

During electroplating, the coated metal or other insoluble material is used as the anode, the workpiece to be plated is used as the cathode, and the cations of the coated metal are reduced on the surface of the workpiece to be plated to form a coating. In order to exclude the interference of other cations, and make the coating uniform and firm, it is necessary to use a solution containing the coated metal cation as the electroplating solution to keep the concentration of the metal cation of the coating unchanged. The purpose of electroplating is to coat a metal coating on a substrate to change the surface properties or dimensions of the substrate.

Electroplating can enhance the corrosion resistance of the metal (the coated metal is mostly made of corrosion-resistant metal), increase the hardness, prevent abrasion, improve the conductivity, smoothness, heat resistance and surface beauty.

The plating is mostly a single metal or alloy, such as titanium, palladium, zinc, cadmium, gold or brass, bronze, etc.; There are also diffuse layers, such as nickel-silicon carbide, nickel-fluoride and fossilite; There are also cladding layers, such as copper-nickel-chromium layers on steel, silver-indium layers on steel, etc. In addition to iron-based cast iron, steel and stainless steel, the base materials of electroplating also include non-ferrous metals, or ABS plastics, polypropylene, polysulfone and phenolic plastics, but the plastic must be specially activated and sensitized before plating.

The main thing is that the front road is not treated well, and there will be, whitish, blistering, pockmarking, fogging, scratches, etc.

Lack of surface flatness makes BGA-type devices more susceptible to virtual soldering.

Plating in circuit boards refers to the phenomenon that metal is plated during the electroplating process where there should not be metal between the pads. There are many reasons for bleed-through, which need to be investigated according to the actual situation to get the real cause

1. The water washing before electroplating is not sufficient, and there is residual liquid between the pads;

2. The current is too large during electroplating, and the electroplating deposition speed is too fast, which can also cause seepage;

3. If the concentration of electroplating solution is abnormal or the composition is abnormal, the laboratory needs to analyze the concentration one by one.

In short, similar process problems need to be followed up and analyzed by process engineers, and cannot be simply judged based on experience.

Is it normal to burst out of light energy, will it cause infiltration?

The PCB production methods of electronic enthusiasts mainly include thermal transfer method, photosensitive wet film method, and photosensitive dry film method. The etching agent has environmentally friendly ferric chloride (FeCl3) and fast hydrochloric acid + hydrogen peroxide (HCl + H2O2). Commonly used PCB drawing software includes Protel99SE and other Protel series software.

Photosensitive dry film + ferric chloride is the best choice for amateurs.

Imaging (forming, wire making).

The first step in the process is to establish the routing of the parts that are connected to each other. We use subtractive transfer to represent the working negative on a metal conductor. This technique involves covering the entire surface with a thin layer of copper foil and eliminating any excess parts.

Additive pattern transfer is another lesser-used method, which is to apply copper wire only where it is needed, but we won't talk about it here.

If you are making a double-sided board, then the PCB substrate will be coated with copper foil on both sides, and if you are making a multi-layer board, the next step will be to glue the boards together.

Positive photoresist is made of a photosensitive agent that dissolves under illumination (negative photoresist decomposes if it is not illuminated). There are many ways to treat a photoresist on a copper surface, but the most common way is to heat it and roll it on a surface containing a photoresist (known as a dry film photoresist). It can also be sprayed on the top in liquid form, but the dry film type provides a higher resolution and can also produce thinner wires.

The hood is just a template for the PCB layer in manufacturing. A hood covering the photoresist on the PCB prevents part of the area of the photoresist from being exposed to UV light (assuming a positive photoresist is used). These areas that are covered by photoresist will be used for wiring.

After the photoresist is developed, the other bare copper parts are etched. The etching process can either dip the board in the etching solvent or spray the solvent onto the board. Generally used as etching solvents, ferric chloride (ferric chloride), alkaline ammonia (alkaline ammonia), sulfuric acid plus hydrogen peroxide (sulfuric acid + hydrogen peroxide), and copper chloride (cupric chloride) oxidize it through oxidation reaction (such as Cu+2FeCl3=CuCl2+2FeCl2).

After etching, the remaining photoresist is removed. This is called stripping.

Small current. Control the pH of the plating bath.

Plating at the same time brother round vibrate.

Timely replenishment of the copper of the yang shouting dust tanji.