Integrated cooling for Si-based microelectronics

Abstract

Thin film thermoelectric coolers are advantageous for their high cooling power density and their potential integrated applications. Si/sub 1-x/Ge/sub x/ is a good thermoelectric material at high temperatures and superlattice structures can further enhance the device performance. Si/sub 1-x/Ge/sub x/ and Si/sub 1-x/Ge/sub x//Si superlattice structures were grown on Si substrates using molecule beam epitaxy. Si/sub 1-x/Ge/sub x/ and Si/sub 1-x/Ge/sub x//Si superlattice thin film microcoolers with film thickness of the order of several microns were fabricated using integrated circuit processing technology. Micro thermocouples and integrated thermistor sensors were used to characterize these coolers. Maximum cooling power density on the order of hundreds of watts per square centimeter was measured at room temperature. It is possible to monolithically integrate these coolers with Si-based microelectronic devices for localized cooling and temperature stabilization.