LED Thermal Interface

Effective cooling relies on solid thermal conductivity. Therefore, thermal interfaces are used in between the components and the cooling unit. This can be a simple heat sink, a thermal assembly, or a housing. The thermal interface has to ensure maximum thermal coupling.

Although not visible to the naked eye, the housing of a component is not flat. On a microscopic level, the surface is very rough and the same applies to the surface of the heat sink. The resulting air gaps which exist between the two surfaces are filled by using a thermal interface.

But a thermal interface does more than just filling up gaps! The material also ensures that the heat is transferred uniformly to the cooling unit, with better cooling as a consequence. Thicker, softer thermal interface materials can also help in absorbing mechanical stress. Because of the wide variety of cooling solutions that are needed, Luxendi offers a variety of thermal interfaces, such as gap fillers, electrically insulating or conductive interfaces, thermal tapes, pastes, greases, and even phase changing interfaces.

Overview of thermal interfaces:

• Gap fillers
  Gap fillers. Thermal interface materials of up to 8W/mK to fill gaps, available in thicknesses ranging from 0.25mm to 10.5mm (at increments of 0.25mm). The softer types (05 shore 00) are ideally suited for absorbing mechanical stress or height differentials. Various materials are also silicone-free, high-recovable, dispensable, and can be provided with special coatings and/or other materials.
• Electrically insulating interfaces
  Thermally conductive material with a high electrical insulating property (up to 10,000V or higher). These materials are available in various thicknesses (ranging from 0.076 to 0.76mm), and can also be cut as required and delivered on a roll.
• Electrically conductive interfaces
  Thermally conductive material which is also electrically conductive (advantageous for EMC, also known as cool pad shields).
• Thermal tapes
  Double-sided thermally conducting sticky tape: the sticking function takes precedence over heat conduction.
• Thermal pastes and greases
  Various types of thermal pastes, up to 3.8W/mK, even silicone-free, and in various formats such as sealant guns or containers for an automated production process.
• Phase changing interfaces
  For optimal thermal conductivity for processors we recommend 'phase change' materials. When heated to around 50°C, the thermal interface will pour out slightly and fill any remaining gaps. Available in thicknesses ranging from 0.076 to 0.40 mm and in screen printable versions up to 5.4W/mK.
• Thermally conductive PCB materials
  To be placed in between two components to improve heat transfer. These copper structures are laminated inside the PCB. Knowledge of the design is required, but heat extraction can be improved eight to ten times.

Luxendi can assist during the various production processes.

Within each category, Luxendi offers a variety of products that each tailor to the cooling requirements of the application and the allocated budget. For simple, moderate heat conduction there are economical options, while more demanding cooling needs will require more expensive materials with a performance of up to 6W/mK.

Learn more about Laird Thermal Systems and Laird Performance Materials