Packaging and assembly

What material is most widely used as the base material of printed circuit boards in electronics?

  1. AGlass-fiber cloth impregnated with epoxy resin (such as FR-4)
  2. BSingle-crystal silicon
  3. CA pure copper plate
Show answer and explanation

Answer: A. Glass-fiber cloth impregnated with epoxy resin (such as FR-4)

Typical PCBs use as their insulating base a material made by impregnating glass-fiber cloth with epoxy resin and curing it (such as FR-4), with copper-foil wiring on the surfaces and inner layers. High-frequency boards also use special resin bases with low dielectric loss.

  • A. Correct. Glass-epoxy (such as FR-4) is widely used.
  • B. Single-crystal silicon is a chip material and is not used for PCBs.
  • C. Copper is the wiring material; the base must be an insulator.
Practice this topic Back to topic

More Packaging and assembly questions

  1. Why are the molding compounds of many plastic packages black?
  2. In high-pin-count BGA packages, why are many of the balls assigned to power and ground?
  3. In wire bonding that forms a ball, where is the first bond (ball bond) generally made?
  4. What is the main purpose of heating packages in an oven for some time after molding (post-mold cure)?
  5. What is the defect called in which bonding wires are pushed aside and deformed by the resin flow during molding?