Creative Materials announces a new product that is customized for thermal management applications-125-31C, Syringe-Dispensable Thermally Conductive Epoxy Adhesive, which joins the standard product line of thermally conductive epoxies, including 109-12, 108-50, and 111-17. Formulated for use in the manufacture of computer components and LEDs, these products are highly effective thermal epoxies for the interface between a heat-producing component and a heat-sink.

LED Adhesive

Applications

Modern electronicsdesign increasingly depends on components that generate a significant amount of heat-CPUs, power diodes, power transistors are some examples. In addition, the ongoing trend toward product miniaturization requires that efficient thermal management is an essential part of modern and future electronicsdesign. Heat must be removed quickly and efficiently in order to prevent premature component failure and extend the life of the component.

The rapidly expanding industry of light emitting diodes (LEDs) provides a good example of effective heat management. LEDs are replacing more traditional lighting methods (fluorescent and incandescent) in applications such as LCD TV backlights, electronic signs and displays, as well as new areas such as daylight automobile headlights. The heat generated by LEDs must be removed to ensure optimal performance.

Heat Removal

Newtons law of cooling states that the rate of heat loss is proportional to the temperature difference between a body and its surroundings. As a components temperature increases, the rate of heat loss per second equates to the heat-per-second produced within the component. For some components, internally produced heat may be high enough to significantly shorten the components working life and eventually cause it to fail.

One heat-removal technique is to attach a heat-sink, artificially increasing surface area in order to allow heat to dissipate. The heat-sink is usually composed of a highly thermally conductive material (e.g., a metal) so the heat can be transferred away from the component. Heat is mainly lost from the surface of a body into its surroundings; therefore, heat-sinks generally are constructed with fins to maximize the surface area per unit volume.

The device and heat-sink are typically solid substrates. In order to facilitate heat transfer between the device and the heat-sink, the gap between them must be eliminated, since air is an extremely poor thermal conductor. The use of a thermal adhesive, such as CMIs 109-12, can significantly improve the thermal interface between the two substrates.

For other types of heat-generating circuitry, e.g power supplies, it may be beneficial to encapsulate the device in a heat-sink enclosure using the thermally conductive CMI 109-12.

Creative MaterialsThermal Management Products: 109-12, 108-50, 111-17, 125-31C

The properties of 109-12 are ideal for most thermal management applications. This product has low viscosity, which reduces the amount of air entrapment introduced into the component interface during application. This property also allows a minimal amount of the product to be applied, keeping thermal resistance as low as possible. A one-component product, 109-12 is easy to use and exhibits minimal shrinkage during curing. A low-stress epoxy, 109-12 features exceptional resistance to thermal-cycling.

Other products in the same family are 108-50 and 111-17, both medium-viscosity products. A new addition to this family is 125-31C, Syringe-Dispensable Thermally Conductive Epoxy Adhesive. This is a flexible, precatalyzed, 100-percent solids, electrically insulating product, featuring chemical resistance and high-temperature properties. All of these products exhibit similar performance characteristics to 109-12. Applications include die attachment, printed circuit board fabrication, advanced material composites, LED attachment, and heat-sink bonding.