Micromachined stack component for miniature thermoacoustic refrigerator

This paper reports a novel miniature MEMS based thermoacoustic refrigerator design for thermal management of electronic and optoelectronic devices. This technique utilizes high-frequency acoustic energy to provide the heat pumping effect. The goal of the Rockwell Scientific-led HERETIC (Heat Removal by Thermo-Integrated Circuits) project is the development and demonstration of a miniaturized refrigeration device based on the thermoacoustic refrigeration principle. Utilizing MEMS technology such as high aspect ratio through wafer etching, bonding and coating techniques, three to four mm thick bonded MEM-TAR (Thermoacoustic Refrigerator) stacks with only 10 to 15 micron wide fine patterns were demonstrated. With our current design, numerical models predict device capability of 1 W heat transport at 20/spl deg/C below ambient when pressurized with 10 atm of He/Ar gas mixture. Preliminary results using 1 atm air achieve as high as 10 degrees of stable cooling below ambient.