Active micro heat transport device using thermal pumping system

We have developed a thermal pumping system for loop-type micro channels, realizing an active micro heat transport device capable of highly efficient cooling. The thermal pumping system makes use of the time change in the vapor pressure of the working fluid as the driving force for fluid circulation. Because it has no mechanically moving elements, it is highly reliable and moreover is effective in preventing deterioration in the heat transport rate due to miniaturization. We set up a system with two thermal pumps within one loop for efficient heat transportation. We fabricated a looped micro-channel, which has a width of 600 /spl mu/m, a depth of 120 /spl mu/m and a channel length of 220 mm. We confirmed a flow rate of 12.5 mm/s at the driving frequency of 1 Hz, enabling a heat transport of 0.16 W.