Key Considerations When Choosing PCB Materials

Design/purpose of the circuit board
It’s important to start with a prototype and consider overall design elements, what the board will be used for, followed by signal integrity requirement, and how it should function in varying environments. Does it need to withstand high temperatures? Do you need a flexible or rigid board?

Heat transfer/conductivity/power thresholds
With the high-speed signals today, overheating is a reality in a wide variety of products, especially those that have a built-in cameras such as cell phones and laptops.

The stackup plays a role in how the mechanical engineer can design and fit the PCB into the device. Is it a single layer or multi-layer? This is the first part of the design process and also refers to the impedance requirements.

Mechanical strength
It’s important to consider whether the materials are electrically strong and mechanically strong. In addition, CTE is critical in microelectronics. Will the materials hold up the PCB’s function?

Electrical signal integrity
This is based on the function of your board and whether it’s categorized as one of the following PCB types: high frequency, high power, high density, or microwave.

Component location
The integrity of the signal can be jeopardized if it flows past certain components that generate “noise” — otherwise known as an interference.

If a multi-layer circuit board is constructed with both flexible and rigid materials, it’s referred to as a rigid-flex board. A rigid-flex board is a 3D interconnect that can be bent and folded into almost any shape. A flexible circuit is just as the name implies; it’s made from thin, flexible material.

Cost of materials (including gold)
The cost of materials typically increases when the printed circuit board contains gold, blind or buried vias, or via filling. This is because an alternate process is needed for fabrication. Line and width spacing below 6 mils may also increase the cost. An ENIG surface finish layer is one of the best ways to protect the surface of a printed circuit board.


  • Arlon: High-performance polyimide laminate and prepreg materials
  • Dupont: The broadest array of electronic materials for flexible and rigid-flex circuits
  • Megtron: Low DK with better stability than PTFEs
  • Isola: High speed Copper-clad laminates and dielectric prepegs
  • Rogers: Enabling step changes in high-frequency, high-speed performance for wired and wireless communications