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CEM-3 PCB Manufacturer & Assembly – One-stop service

Double-sided and multi-layer printed circuit boards are commonly used with FR-4 substrates, a copper-clad flame-retardant epoxy glass cloth board. CEM-3 PCB is a new substrate material for a printed circuit board developed on the basis of FR-4.


1. CEM-3 PCB is a composite copper-clad laminate

FR-4 is made of copper foil and glass fiber cloth impregnated with flame-retardant epoxy resin. The difference between CEM-3 and FR-4 is that it is made of glass cloth and glass mat composite substrate. Also called composite. Not just glass cloth.

The CEM-3 type board is an intermediate layer of an electronic grade non-alkali glass non-woven fabric impregnated with a flame-retardant brominated epoxy resin. And each side of the non-woven fabric is an electronic grade alkali-free glass fiber cloth. It coated with a flame-retardant brominated epoxy resin with copper foil on one or both sides. And it is hot pressed into a copper-clad laminate.

2. CEM-3 performance

CEM-3’s glass transition temperature, dip resistance, peel strength, water absorption, electrical breakdown, insulation resistance, UL index, etc. can all meet the FR-4 standard, the difference is CEM-3 has a lower flexural strength than FR4 and a thermal expansion greater than FR4. CEM-3 metalized hole processing is not a problem, the drilling wear bit has a low wear rate, is easy to punch and punch forming, and has high thickness dimensional accuracy, but the inferior of a metalized hole is slightly poor.

3. CEM-3 market application

UL believes that CEM-3 and FR-4 are interchangeable, so double layer PCB board that use FR-4 are now generally available as replacements. Since CEM-3 and FR-4 perform similarly, it has also become possible to replace them on multi-layer boards. Circuit boards made of CEM-3 are now used in fax machines, copiers, instrumentation, telephones, automotive electronics, and home appliances.


4. Further improvement and development of CEM-3 substrate

In order to further adapt to the SMT assembly of electronic products, the development of light, thin, miniaturized and multifunctional, CEM-3 substrate has been further improved, mainly from the following four aspects.

Optimization of filler The crystal form, viscosity, amount and usage of crystal water of fillers affect the dip resistance of the formed substrate, dimensional stability, reliability and transparency of the hole metallization.
Resin system improvement The use of Novrakak resin improves the high-frequency properties, processability, and reliability of the hole metallization of the substrate.

5. Improvement of non-woven glass mat, the surface treatment of glass fiber is beneficial to improve the insulation resistance under wet conditions.

6. The ratio of the length of the glass fiber can improve dimensional stability.

With the continuous improvement and improvement of the performance of CEM-3 substrates, the world’s applications are becoming more and more popular. In recent years, in addition to Japan, South Korea, and Taiwan, China, the production of CEM-3, the application of development is also very rapid, the growth rate is much higher than FR4, I believe that the next dozen, the new composite substrate will be more development of.