Direct-immersion cooling for high power electronic chips

Several direct-immersion cooling techniques currently under examination are reviewed. They include cooling by means of pool boiling, falling films, channel flow boiling, and jet impingement. Both thermal performance and practical packaging concerns are discussed, and the suitability of each technique for dissipating high heat fluxes from isolated chips and multichip modules is assessed with respect to such considerations as chip junction temperature, cooling uniformity, and critical heat flux (CHF). It is shown that several means are available for greatly increasing CHF in order to satisfy the cooling requirements for future electronic devices. While high cooling fluxes are possible with a number of direct-immersion cooling techniques, the complexity of the coolant conditioning and delivery to the chips should be carefully considered in selecting a suitable cooling technique