Continued miniaturization and demand for high-end performance of electronic devices and appliances have led to dramatic increase in their heat flux generation. Consequently, conventional coolants and cooling approaches are increasingly falling short in meeting the ever-increasing cooling needs and challenges of those high heat generating electronic devices. This study provides a critical review of traditional and emerging cooling methods as well as coolants for electronics. In addition to summarizing traditional coolants, heat transfer properties and performances of potential new coolants such as nanofluids are also reviewed and analyzed. With superior thermal properties and numerous benefits nanofluids show great promises in fulfilling the cooling demands of high heat generating electronic devices. It is believed that applications of such novel coolants in emerging techniques like micro-channels and micro-heat pipes can revolutionize cooling technologies for electronics in the future.

A critical review of traditional and emerging techniques and fluids for electronics cooling

https://iopscience.iop.org/article/10.7567/JJAP.56.05DA04/pdf

Thermoelectric silicides: A review

This paper provides a review of thermoelectric cooling and its application to the cooling of electronic equipment. A background discussion of thermoelectric cooling is provided briefly citing early history, current developments, and the defining thermoelectric heat pumping equations. Several examples are provided of early IBM applications of thermoelectric cooling. An analysis to assess thermoelectric cooling enhancement in terms of increases in allowable power dissipation or chip temperature reduction is described along with results.

Application of thermoelectric cooling to electronic equipment: a review and analysis

An electronic module and method of fabrication are provided employing an integrated thermal dissipation assembly. The thermal dissipation assembly includes a thermoelectric assembly configured to couple to an electronic device within the module for removing heat generated thereby, and a programmable power control circuit integrated with the thermoelectric assembly. The programmable power control circuit allows cooling capacity of the thermoelectric assembly to be tailored to anticipated heat dissipation of the electronic device by adjusting, for a given power source, voltage level to the thermoelectric elements of the thermoelectric assembly. Power to the thermoelectric assembly can be provided through conductive power planes disposed within a supporting substrate. The power control circuit includes one or more voltage boost circuits connected in series between the given power source and the thermoelectric elements of the associated thermoelectric assembly.

Electronic module with integrated programmable thermoelectric cooling assembly and method of fabrication

The trend towards increasing heat flux at the chip and module level in computers is continuing. This trend coupled with the desire to increase performance by reducing chip operating temperatures presents a further challenge to thermal engineers. We will provide an assessment of the potential for module cooling enhancement with thermoelectric coolers. A brief background discussion of thermoelectric cooling is provided citing some of the early history of thermoelectrics as well as more recent developments from the literature. An example analyzing cooling enhancement of a multichip module package with a thermoelectric cooler is discussed. The analysis utilizes closed form equations incorporating both thermoelectric cooler parameters and package level thermal resistances to relate allowable module power to chip temperature. Comparisons are made of allowable module power with and without thermoelectric coolers based upon either air or water module level cooling

An Assessment of Module Cooling Enhancement With Thermoelectric Coolers

Many high power electronic devices, such as power amplifies and multiprocessors, operate at high temperatures close to or at the edge of their reliability, which could severely impact performance and operating lifetime. These devices thus need cooling to improve performance and reliability. Conventional thermal management techniques, most of which are discussed, are not well suited to the specific problem of cooling discrete or localized heat dissipating devices since they generally cool the whole board. Moreover, these techniques have difficulty dealing with the large heat fluxes associated with the high density packaging of power devices. The specific problem of spot cooling of power devices can be very effectively solved by using the combination of diamond substrates and a thermoelectric cooler. The highest power components would be mounted directly on a diamond substrate (ideally the top substrate of the cooler) allowing the cooler/diamond combination to maintain the temperature of the device from a few degrees to tens of degrees below that of the substrate on which the cooler is mounted (diamond or any other high thermal conductivity material). This will allow the device to operate at a low enough temperature to increase both reliability and clockspeed. It has been determined that the highest cooling power densities will be achieved with thin film coolers with cooler leg lengths on the order of 20 to 50 microns. The results of a solid state power amplifier (MMIC) cooled using a diamond/cooler combination are presented and discussed.

J.W. Vandersande

Papers

Thermal management of power electronics using thermoelectric coolers