Thermal Interface Materials

Materials that are used for heat transfer from critical components in electronics.

Greater heat flow away from crucial heat generating processors and other components is the main driver for developing superior thermal interface materials. These materials can be found in LED applications, automotive electronics, power supplies, mobile phones and PCs. A more controlled heat management leads to better performance, longer  lifetime and better reliability (IDTechEx, 2016).

What is Thermal Interface Materials?

A thermal interface material (TIM) is typically a paste, gel or flexible film. It’s used to enhance heat transport from one surface to another, for instance from a hot processor surface to a heat sink. A TIM should be soft as it is required to fill insulating air gaps created by the micro-scale roughness of the two hard surfaces.

Air pockets are large thermal barriers for even modest heat transfer. The degree of heat transfer you achieve depends on the performance of the specific TIM material applied, together with the interfacial resistances of the surrounding materials.

The Thermal Performance

The performance of TIMs matters most in the through plane, or z-direction, of the material. It is important that the heat is transferred out and away to the opposite surface – not sideways.

When comparing TIMs, there are two main elements of overall thermal performance:

The bulk conductivity of the material, meaning heat transfer through a given material, and thermal contact resistance of the system, which is thermal resistance over an interface between two materials.

The TIM’s ability to wet the surface influences the thermal contact resistance of the system. Therefore, a TIM with modest bulk thermal conductivity but a low interfacial resistance may exhibit a lower thermal resistance at system level than a high conductivity TIM with a large interfacial thermal resistance.

Benefits of improved TIMs:

  • Extended life time and improved reliability of electronic devices.
  • Thinner, more compact electronics.
  • Elimination of the need for more costly thermal management methods.

Advantages of CondAlign’s Materials

  • The anisotropic character of the material enables directional heat transfer.
  • Better wetting of the surfaces, leading to better overall heat transfer.
  • Efficient use of the conductive particles, achieving similar heat conductivity with less particles, or better conductivity with the same loading.

Our technology enables soft, flexible films with conductive pathways in the z-direction of the material with a lower particle loading than traditional thermal interface materials.

What are the advantages in choosing CondAlign?

An advantage of the lower particle loading is that the polymer matrix can retain most of its original properties, such as softness and wetting capabilities. The alignment and efficient use of particles also saves costs compared to stochastic particle distribution.

Our TIMs have demonstrated up to 100% improvement in thermal conductivity by aligning the particles, compared to other films of equal particle type and loading. The magnitude of this enhancement of conductivity is higher when the particle loading is lower.