The materials used for PCBs (Printed Circuit Boards) vary depending on the application, performance requirements, and environmental conditions. Here are the most common materials:
These materials serve as the foundation of the PCB, offering structural support for the electronic components mounted on it.
- FR-4 (Flame Retardant 4)
- Polyimide
- Metal Core PCB (Aluminum, Copper)
- CEM-1 and CEM-3 (Composite Epoxy Material)
- Material: Thin layers of copper foil are laminated to the substrate.
- Properties: Copper is highly conductive, so it is used for creating the circuit traces.
- Common Uses: The copper layers form the conductive pathways for electricity.
- Material: Epoxy, liquid photoimageable soldermask (LPI)
- Properties: Applied over the copper traces to protect them from oxidation, corrosion, and short circuits. It is typically green but can be found in other colors like red, blue, or black.
- Common Uses: All PCB designs use soldermask for protection.
- Material: Non-conductive ink, typically epoxy-based or UV curable.
- Properties: Used for adding labels, logos, and component identifiers on the PCB.
- Common Uses: Helps in assembly and testing processes.
- ENIG (Electroless Nickel Immersion Gold): A popular choice for high-performance boards due to its excellent corrosion resistance and good conductivity.
- HASL (Hot Air Solder Leveling): Common for consumer electronics, it's affordable but may have uneven surface layers.
- OSP (Organic Solderability Preservative): A thin layer of organic material that protects the copper until soldering occurs. It's used in cost-sensitive applications.
Choosing the right PCB material depends on several factors like the temperature range, flexibility, cost, and electrical performance requirements.
