For the past 50 years, the thermal management industry has offered only heatsinks, fans, and thermal grease as methods for electronics thermal management. While these techniques have been refined and improved over the years, nothing new has been introduced to address the exponential growth of thermal issues in modern-day electronics.
The electronics industry has reached a breaking point — a sort of thermal overload. As components, packages, and systems continue to shrink in size, we are simultaneously adding functionality. The heat generated in these dense electronic systems can be quite large and in-turn lead to significant increases in temperatures that cause component-, device-, and system-level failures.
The answer to these problems has always been to use a larger fan or larger heatsink to move all of the heat out of the electronic package and into the system environment. That’s easiest but it costs the most to manage.
The EPA estimates that by 2011, energy consumption by U.S.-based data centers could top more than 100B kwh, representing an annual cost of at least $7.4B. According to a recent study by Emerson Network Power, 50% of the power consumed in data centers goes toward battling heat with air conditioning.
The most efficient thermal management system involves embedding thermal management functionality at the source of the heat to remove excess heat before passing the remaining heat on to the next level. The cost of implementing thermal management solutions can be compared to the level in which the solution is introduced. Implementing heatsinks, fans, and large-scale cooling creates an energy savings potential. Introducing localized cooling in the overall thermal management design translates to a greater cost savings potential at the rack and data center levels.
Localized thermal management solutions have been introduced∗ that work deep inside electronic components using thin-film thermoelectric structures known as thermal bumps. The thermal bump is made from a thin-film thermally active material that is embedded into flip chip interconnects (in particular copper pillar solder bumps) for use in electronics packaging.
Thermal bumps act as solid-state heat pumps and pull heat from one side of the device and then transfer it to the other as current is passed through the thermoelectric material. Thermal bumps today are already extremely small — 238