What To Do If Circuit Board Is Covered With Copper?

What to do if circuit board is covered with copper?

PCB circuit board copper clad laminate problem one, to be able to track down.

It is impossible to manufacture any number of PCB circuit boards without encountering some problems, which is mainly due to the material of the PCB copper-clad laminate. When quality problems occur in the actual manufacturing process, it seems often because of the PCB substrate material. Even a carefully written and effectively implemented PCB laminate technical specification does not specify the test items that must be carried out to determine that PCB laminate is the cause of production process problems. Here are some of the most commonly encountered PCB laminate problems and how to confirm them.

Once encountering PCB laminate problems, you should consider adding to the PCB laminate specification. Generally, if this technical specification is not enriched, it will cause continuous quality changes and consequently lead to product scrapping. Usually, the material problems caused by the quality changes of PCB laminates occur in the products manufactured by manufacturers using different batches of raw materials or using different pressing loads. Few users can hold a large number of sufficient records, so that they can distinguish a specific pressing load or material batch at the processing site. Therefore, it often happens that the PCB is continuously produced and mounted with components, and the warpage continuously occurs in the solder bath, thereby wasting a lot of labor and expensive components. If the batch number of the charge is immediately available, the PCB laminate manufacturer can check the batch number of the resin, the batch number of the copper foil, and the curing cycle. In other words, if the user cannot provide continuity with the quality control system of the PCB laminate manufacturer, this will cause the user to suffer long-term losses. The following describes the general issues related to substrate materials in the PCB circuit board manufacturing process.

PCB circuit board copper clad laminate problem two, surface problem

Symptoms: Poor adhesion of printing materials, poor adhesion of plating, some parts cannot be etched away, and some parts cannot be soldered.

Available inspection methods: visual inspection is usually performed by forming visible water marks on the surface of the board:

Possible reason:

Because of the very dense and smooth surface caused by the release film, the uncoated copper surface is too bright.

Normally on the uncoated side of the laminate, the laminate manufacturer did not remove the release agent.

Pinholes on the copper foil cause the resin to flow out and accumulate on the surface of the copper foil, which usually occurs on copper foils that are thinner than 3/4 ounce weight specifications.

Copper foil manufacturers apply excess antioxidant to the surface of the copper foil.

Laminate manufacturers have changed the resin system, stripping thin, or brushing methods.

Due to improper operation, there are many fingerprints or grease.

Use oil when punching, cutting or drilling operations.

Possible solutions:

Before making any changes in laminate manufacturing, cooperate with the laminate.

Manufacturer and specify the user's test items.

It is recommended that laminate manufacturers use fabric-like films or other release materials.

Contact the manufacturer of the laminate to inspect each batch of copper foil that failed; request a solution recommended by removing the resin.

Ask the manufacturer of the laminate for the removal method. It is generally recommended to use hydrochloric acid, followed by mechanical grinding to remove it.

Contact the laminate manufacturer to use mechanical or chemical elimination methods.

Educate personnel in all processes to wear copper clad plates with gloves. Find out whether the laminated board has suitable padding paper or packed in the bag during transportation, and the padding paper has a low sulfur content, and the packaging bag is free of dirt. Take care to ensure that no one is touching when using a detergent containing silicone Copper foil.

Degrease all laminates before plating or graphic transfer process.