Ultra-precision PCB Fabrication, High Frequency PCB, High Speed PCB, IC Substrate, Multilayer PCB and PCB Assembly.
The most reliable PCB custom service factory.
Microwave Tech

Microwave Tech

Microwave Tech

Microwave Tech

How to do if PCB circuit board is covered with copper laminate
2021-08-30
View:52
Author:Fanny

Some of the most common PCB circuit board problems encountered and how to identify them are listed here. In case of PCB laminate problems, it should be considered to be added to the PCB laminate specification. How to solve the problem of copper clad laminate of PCB circuit board?


Ⅰ、To be able to search

It is impossible to manufacture any number of PCB board without running into some problems, mainly due to the material of PCB copper-clad laminates. When quality problems occur during actual manufacturing, it often seems to be the PCB substrate material that is the cause of the problem. Even a carefully written and implemented technical specification for PCB laminates does not specify the tests that must be performed to determine that PCB laminates are the cause of the manufacturing process failure. Here is a list of some of the most commonly encountered PCB laminate problems and how to identify them.


PCB circuit board


In case of PCB laminate problems, it should be considered to be added to the PCB laminate specification. Often, failure to flesh out this technical specification results in constant quality changes and subsequent product obsolescence. Often, material problems due to changes in PCB laminate quality occur in products manufactured with different batches of raw materials or with different pressing loads. Few users have enough records to distinguish a particular pressing load or batch of material at the processing site. As a result, a lot of labor and expensive components are wasted as the PCB is continuously produced and loaded with components and continuously warped in the solder groove. If the batch number is immediately available, the PCB laminate manufacturer can check the batch number of the resin, the batch number of the copper foil, the curing period, etc. In other words, if the user fails to provide continuity with the quality control system of the PCB laminate manufacturer, the user itself will suffer in the long run. The following are general issues related to substrate materials in PCB manufacturing.


Ⅱ 、Surface problems

Signs: poor adhesion of printing material, poor adhesion of coating, failure to etch off certain parts, and failure to solder certain parts.

Available inspection methods: Visual inspection is usually performed by forming visible water lines on the surface of the plate:

2.1 Possible Causes:

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

Usually on the uncoppered side of the laminate, the laminate maker has not removed the release agent.

Pinholes in copper foil, causing resin to flow out and deposit on the surface of copper foil, usually occurs on copper foil thinner than 3/4 oz weight specification.

Copper foil makers coat the foil with excessive amounts of antioxidants.

Laminate makers have changed resin systems, stripping, or brushing methods.

There are a lot of fingerprints or grease stains due to improper handling.

Apply oil during blanking, blanking or drilling operations.


2.2 Possible solutions:

Work with the laminate manufacturer and define the user's test program before any changes are made to the laminate manufacture.

Laminate makers are advised to use fabric films or other release materials.

Liaise with the laminate manufacturer to inspect each batch of copper foil that is not acceptable. Ask for solutions to remove resins.

Ask the laminate manufacturer for a method of removal. Hydrochloric acid is generally recommended, followed by mechanical scrubbing to remove it.

Contact the laminate manufacturer for mechanical or chemical removal.


Teach all process personnel to wear gloves to handle copper cladding. Make sure that the laminates are properly padded or bagged during transportation, that the pads are low in sulfur, that the bags are free of dirt, and that no one touches the copper foil while using a detergent containing silicone.