Thermally conductive thermal pads are essential components of thermal management in electrical applications. They establish thermal contact between heat sources e.g. power modules, FBGAs, BGAs, MOSFETs, coils, etc. and heat sinks e.g. extrusion heat sinks, liquid coolers, heat pipe assemblies or vapour chambers and ensure targeted, rapid heat dissipation. The optimum connection keeps the operating temperature of the components low, optimises the efficiency of the application and maximises the life time of the components. HALA’s thermal pads also stand out because they have thermal conductivities of up to 20 W/mK. Learn more.
GAP-FILLERElectronic applications today consist of a large number of components that vary in height.
This leads to gaps and tolerances that have to be compensated. For this purpose, we recommend the gap-fillers from HALA.
- 2K dispensable
- Soft, ultra soft, elastic, plastic, dispensable
- Double or single sided adhesion through laminate or surface treatment or adhesive
- Reinforcement by glass fiber laminate
- Silicone, silicone-free or low volatile siloxanes (LV)
SILICONE FOILS AND FILMSUnder pressure thermally conductive foils achieve an excellent compliance to contact surfaces thus the total thermal resistance is minimized. At the same time a permanent electrical insulation is assured.
- Silicone foil fibreglass reinforced
- Silicone foil not reinforced
- Insulating film silicone coated
- Material thicknesses of 0.05 up to 1 mm
- Sheet or roll
- Die cut parts
- Kiss cut parts
- With or without adhesiveness
- Reinforcement by glass fiber laminates or Polymide
PHASE CHANGE MATERIALDuring warm-up over phase change temperature, phase change materials (PCM) start filling up surface-specific roughnesses and/or unevenesses and expel any air enclosures from micro structures.
- PCM coated polymide film
- Aluminum film PCM coated
- PCM film
- Pre-applicable printable PCM compounds
- Extremely low thermal resistances through optimum contact
- Easy pre-assembly
- Process reliable coating thicknesses
- Pre-applied and dry-to-the-touch printable types
- Ideal replacement of messy thermal grease
GRAPHITE FOILSGraphite foils consist of more than 98% pure natural graphite or are processed of synthetic pyrolytic graphite.
- Sheet or Roll (natural graphite)
- Die cut parts
- Without or with tackiness
- With or without dielectric films (PEEK, PI, PET)
- Thermal conductivities up to 1,950 W/mK in-plane and 25 W/mK in through z-direction
- Heat spreading from hot spots
- Low thermal contact resistance through good surface compliance
- Very low weight
- Extreme temperature range up to 400°C
- No dry-up, migrating, run out or pump out
- EMI-shielding through high electrical conductivity as side effect
- 180°C foldable (pyrolytic graphite)
Thermal pads are foils for the optimal conduction of heat loss. Dielectric thermal pads are used for electrically non-insulated components. These thermal pads are usually made of silicone, polymers or plastics, e.g. polyimide, and are usually filled with thermally conductive ceramics such as aluminium oxide, aluminium hydroxide, boron nitride or zinc oxide. If electrical insulation is not required, graphite foils or phase change foils and films are usually applied.
Thermal pads are foils and films made of a particularly heat conducting material. The way it works is simple: When applied to a component in which heat is lost during operation, the heat conducting pad displaces the air that would otherwise have taken up this space. The heat of the component is therefore no longer dissipated to the ambient air via convection, but via conduction through the thermal pad to the heat sink. This has a much better thermal conductivity than air and conducts the heat quickly. Especially when it comes to heat-conducting thermal pads from HALA: with a thermal conductivity of up to 20 W/mK, HALA gap fillers, for example, are far above the thermal conductivity of air (0.0262 W/mK).
To find the right thermal pad for an application, a number of factors play a role, such as the dimensions of the gap to be bridged and the mechanical tolerances. In order to optimally adapt a heat conducting pad to this, we now even have the option of designing some gap-filler types in three dimensions or as sets. The thermal and dielectric properties are crucial for the selection of the appropriate heat conducting pad. At HALA we offer various thermal pads with a thermal conductivity of up to 20 W/mK, which can be either electrically insulating or non-insulating. Above this, the mechanical compression and contact behaviour is essential, which determines how good the compliance, thermal contact resistance and wetting are.
This information usually already indicates the material that is best suited for use in the application. However, if there are specifications from your side, we will certainly find a solution for this as well. Many of our customers, for example, are from the automotive industry and prefer silicone-free solutions. Another factor in selecting the right thermal pad is the temperature range that the material has to withstand. Here, too, possible solutions differ significantly.
In summary: The most important properties for selecting a thermal pad
– Thermal conductivity λ in W/mK
– Thermal resistance Rth in K/W
– Dielectric strength in kV/mm or breakdown voltage in kV
– Thickness range
– Pressure-deflection compression behaviour
– Operating temperature range
– Material specifications, e.g. silicone freeness
In addition, there are many other criteria regarding the selection, such as UL registration according to VO, the possibilities for processing and assembly on site, the project budget (design-to-cost) and the time window for realisation.
You want to make it easy for yourself? Contact one of our contact persons directly – we are sure to find a suitable solution for you.
Thermal pads are very often used in laptops and computers because, compared to thermal greases, they are not liquid or pasty, with the risk of smearing and ageing. On the one hand, this involves dissipating the heat lost from the battery, and on the other hand, cooling processors, i.e. CPU (Central Processing Unit). With particularly powerful laptops or computers, for example in the gaming sector or with graphics cards, the processor is at risk of overheating quickly. For this reason, work is continuously being done on the connection of the processor to the heat sink. This is easy with a high-performance thermal pad, as the heat conducting pad with its contact surface complies optimally to the processor to be connected and the cooling works effectively right from the start. Phase change materials (PCM) as films are a particularly effective variant that melt when heated and cover the surfaces during initial heat cycle so that the contact surfaces are completely and optimally wetted with minimal thickness (bond line). The result is the best possible thermal contact.
Thermal greases such as putties and pastes are a popular and established alternative to thermal pads. Thermal greases are usually paste-like compounds consisting of one component as a carrier, e.g. silicone, with thermally conductive fillers mixed in. Thermal conductive pastes are applied in liquid form, which allows flexible application. However, in order to ensure the repeatability of the application quality, hugh efforts are dedicated on the precision and time of the assembly process, which leads to costs that are often not accepted. Thermal pads, on the other hand, are easy and process-safe to apply without contamination and quickly cover a large area. A particularly effective alternative is provided by phase change materials (PCM) as films, which soften when heated and wet the surfaces during initial heat-cycle so that the contact surfaces are completely and optimally wetted with minimal thickness (bond line). The result is the best possible thermal contact.
Accordingly, which is more suitable for your project depends on many factors. If you are undecided, simply get in touch with one of our contact persons – we will be happy to advise you free of charge at any time.
As a rule, either a thermal pad or a thermal grease is used. Both together would be highly complex and do not lead to the desired goal. On the contrary: the structure becomes too thick and the thermal gap to bridge larger. Also, several thermal pads should not be stacked, as heat can increase if the connection is not made professionally by laminating. It is therefore best to find an integrated suitable thermal conduction solution from the beginning that fits the project optimally, without any bricolage.
A traditional exception is mica plates as dielectric discs. These used to be used as thermal pads when connecting electrical components and heat sinks. For good thermal contact, these fragile discs were combined with thermal paste. However, this is not necessary with the thermal pads offered by HALA and would only worsen the effect.
If you look online, you will usually find a large number of online shops where private users can buy prefabricated thermal pads individually or in a small quantity. These shops are often not designed for business customers, nor are prefabricated standard solutions. In addition, in a professional environment, it must be ensured that the thermal management solution is one that can be used over the long term, can be scaled cost-effectively and is therefore also suitable for large production quantities. At HALA, we offer you precisely this buying option.
With us, you can buy thermal pads in large quantities. Most importantly, our individual expert consultancy can help you find the optimal solution for each of your projects, whether that ends up being a thermal pad or a customised thermal management system.
The best thing to do is to contact us directly – we can advise you at any time, free of charge and conveniently online.