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HEAT SPREADERS
A heat spreader is a device that improves the distribution of heat.
Novel Concepts has developed and patented IsoSkin™, a thin planar Superconducting Heat Spreader (flat heat pipe), with effective thermal conductivities as high as 10,000 W/m*K.
Available as thin as 500 microns, these IsoSkin heat spreaders can be used to replace the skin (outer shell) of portable electronics, often eliminating the need for heat sinks and fans. These thin flat IsoSkin heat pipes are also being used to dramatically improve heat sink and cold plate performance, by reducing the thermal constriction resistance inherent in high power density applications such as microprocessors, Peltier (solid state thermoelectric) modules, and power semiconductors.
"Novel Concepts solved the engineering dichotomy associated with porous wick structures (used in traditional heat spreaders), such as sintered metals, by separating the liquid transport mechanism from the heat transfer mechanism, allowing independent optimization." (Daniel Thomas, Chief Technology Officer)
At the core of the IsoSkin heat spreader technology is its patented planar capillary. This planar capillary provides the necessary amount of liquid to handle power densities up to hundreds of watts per square centimeter. IsoSkin's planar capillary is primarily engineered for liquid transport, as opposed to antiquated porous wick structures, which act as both a liquid transport medium and as a heat transfer structure.
The planar capillary in the IsoSkin heat spreader has such high liquid transport capacity, that additional internal microstructures (wick) are not required for applications having power densities less than 20 watts per square centimeter.
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IsoSkin™ Superconducting Heat Spreader™
(based on 162mm x 162mm x 1.5mm sized unit)
(heated on one edge, cooled on opposing edge)
As thin as a U.S. penny (1.5 millimeters), this new IsoSkin™ Superconducting Heat Spreader technology is capable of transferring over 250 watts, with a thermal efficiency 20 times greater than copper, and 4 times greater than the highest purity diamond. IsoSkin is also 60% lighter than copper, facilitating today’s “thinner and lighter” design trends.
Click on the Thermal Profiles below, to see how IsoSkin™ performs against copper and aluminum.
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 to minimum temperature (115°F) differential is only 8°F. This same sized heat spreader from copper has a maximum temperature (270°F) to minimum temperature (96°F) differential of 174°F, and even worse, aluminum has a maximum temperature (354°F) to minimum temperature (90°F) differential of 264°F.'))
 to minimum temperature (96°F) differential is 174°F. This same sized heat spreader from aluminum has a maximum temperature (354°F) to minimum temperature (90°F) differential of 264°F. Amazingly, an IsoSkin™ Superconducting Heat Spreader™ has a maximum temperature (123°F) to minimum temperature (115°F) differential of only 8°F.'))
 to minimum temperature (90°F) differential is 264°F. This same sized heat spreader from copper has a maximum temperature (270°F) to minimum temperature (96°F) differential of 174°F. Incredibly, an IsoSkin™ Superconducting Heat Spreader™ has a maximum temperature (123°F) to minimum temperature (115°F) differential of only 8°F.'))
 of portable electronics such as notebook computers, web pads, cellular phones, PCMCIA cards, hard drives, or handheld PDA\'s, eliminating the need for heat sinks and fans. IsoSkin can be fabricated as thin as 500 microns (thinner than a credit card), using any metal. Utilizing heat pipe physics, IsoSkin can achieve thermal conductivities 4 times greater than the highest purity diamond (up to 20 times greater than copper).'))
, which is formed between the evaporator sidewall (red) and the condenser sidewall (blue). Also note that due to capillary physics, the planar capillary is only formed where the distance between the sidewalls is small. In other words, where the distance between sidewalls is large (embossed region), surface tensions cannot support the planar capillary. These larger non-capillary regions are for vapor transport.'))
, which is formed between the evaporator sidewall (red) and the condenser sidewall (blue). Also note that due to capillary physics, the planar capillary is only formed where the distance between the sidewalls is small. In other words, where the distance between sidewalls is large (embossed region), surface tensions cannot support the planar capillary. These larger non-capillary regions are for vapor transport.'))
 formed to the inside contours of a notebook computer skin (shell). This IsoSkin device was developed to uniformly distribute heat from multiple heat sources (red) to the plastic computer skin, eliminating the need for additional heat sinks and fans.'))
, with inlaid radial convoluted cooling fins. Developed for an electronics company, this low profile (5mm without fan) heat sink has a total thermal resistance of 0.36 °C/W. The volumetric thermal efficiency is 0.026 W/°C/cc. Total weight 397 grams (including fan).'))
 for a notebook computer. Only 1mm thick, this thin planar heat spreader replaces multiple 5mm diameter heat pipes, while substantially improving thermal performance.'))
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. This thin planar IsoSkin heat spreader provides a very low thermal resistance between the microprocessor and the cooling fins. With an effective thermal conductivity greater than solid diamond, this IsoSkin heat spreader solves the constriction resistance problem inherent with solid metals. Total weight 139.2 grams.'))
, which thermally planarizes the uneven junction temperatures caused by the non-uniform power distribution of an integrated circuit. For instance, a one square centimeter integrated circuit chip, which dissipates 100 watts, would dissipate 1 watt per square millimeter, if the power density were equally distributed across its surface. However, a typical integrated circuit has various types of circuits across its surface, such as IO, memory, registers, and arithmetic logic, each performing different tasks, with each region having a different power density. In fact, this non-uniform power density, or distribution, can be as low as 0.1 watts per square millimeter, and as high as 3.0 watts per square millimeter. In the regions where the power density is 3.0 watts per square millimeter, thermal constriction resistance will cause the peak temperature to be at least 3 times the average temperature, resulting in a cooling capacity specification at least 3 times greater than the thermally planarized cooling specification. In other words, IsoDie may reduce the overall cooling specification by a factor of three or more.'))
