CEM-3 printed circuit boards

CEM-3 printed circuit boards features and applications

CEM-3 is a type of composite copper-clad laminate. Its glass transition temperature, solder resistance, peel strength, water absorption, electric breakdown strength, insulation resistance, and UL indicators all meet the standards of FR-4. The differences are that CEM-3’s flexural strength is lower than that of FR-4 and its thermal expansion coefficient is higher than that of FR-4.

Description

CEM-3 Composite Copper-Clad Laminate for PCBs

CEM-3 is a composite copper-clad laminate used for printed circuit boards (PCBs). It is made by reinforcing alkali-free glass fiber cloth and glass fiber mat with epoxy resin and then pressing copper foil onto the surface. The electrical performance, heat resistance, and flame retardancy of CEM-3 are basically comparable to those of FR-4, but its mechanical strength is slightly lower and its coefficient of thermal expansion is slightly higher. The most notable feature of CEM-3 is that its core is generally white or light gray, with a smooth surface that is easy to drill and process, making it suitable for double-sided PCB manufacturing. CEM-3 is widely used in electronic products that require a balance between performance and cost, such as household appliances, instruments and meters, automotive electronics, etc.

Main Features of CEM-3

  • Electrical properties are comparable to FR-4.
  • High reliability of PTH (plated through holes).
  • Smooth surface, with the core mostly white or light gray.
  • Good flame retardancy and insulation.
  • Easy to drill and machine.
  • Lower cost than FR-4, with high cost-effectiveness.
  • Suitable for double-sided PCB manufacturing.

Main Applications

  • Instruments and meters.
  • Information appliances.
  • Automotive electronics.
  • Automatic controllers.
  • Game consoles.
  • Household appliances.
  • Communication equipment.

Common Specifications

  • Base thickness: 1.0mm, 1.5mm.
  • Copper thickness: 35μm.
  • Board size: 1044×1245mm.
  • Surface finishes: HASL (Hot Air Solder Leveling), ENIG (Electroless Nickel Immersion Gold), OSP (Organic Solderability Preservative).