SiGeC/Si superlattice microcoolers

Abstract

Monolithically integrated active cooling is an attractive way for thermal management and temperature stabilization of microelectronic and optoelectronic devices. SiGeC can be lattice matched to Si and is a promising material for integrated coolers. SiGeC/Si superlattice structures were grown on Si substrates by molecular beam epitaxy. Thermal conductivity was measured by the 3 method. SiGeC/Si superlattice microcoolers with dimensions as small as 40ϫ40 m 2 were fabricated and characterized. Cooling by as much as 2.8 and 6.9 K was measured at 25°C and 100°C, respectively, corresponding to maximum spot cooling power densities on the order of 1000 W/cm 2 . © 2001 American Institute of Physics. ͓DOI: 10.1063/1.1356455͔Thermoelectric ͑TE͒ refrigeration in a solid-state active cooling method with high reliability. Bi 2 Te 3 -based TE coolers are widely used for cooling and temperature stabilization of microelectronic and optoelectronic devices, but their processing is a bulk technology and is incompatible with integrated circuit fabrication process. Solid-state coolers monolithically integrated with microelectronic and optoelectronic devices are an attractive way to achieve compact and efficient cooling. It can lower the cost of fabrication and packaging, and can selectively cool individual key devices instead of the whole chip. However, the thermoelectric figure of merit ͑ZT͒ is quite low for most of the semiconductors used in microelectronics and optoelectronics. This makes it difficult to get high cooling performance. Recently heterostructure thermionic and superlattice coolers have been proposed, and theoretical calculations show that large improvements in ZT can be achieved and efficient refrigeration becomes possible with coolers made of conventional semiconductor materials.

Molecular dynamics study of the lattice thermal conductivity of Kr/Ar superlattice nanowires

“…Semiconductor superlattices (SL) are of great interest due to their potential applications in thermoelectric and optoelectronic devices [1,2]. Superlattice structures provide the possibility of decreasing materials' thermal conductivity while retaining their electrical conductivity, thus achieving a high thermoelectric figure-of-merit and improving the performance of thermoelectric devices.…”

Accurate measurements of cross-plane thermal conductivity of thin films by dual-frequency time-domain thermoreflectance (TDTR)

“…In these applications, knowledge of the cross-plane thermal conductivity is crucial for designing more efficient materials 4 or improving the thermal management of the devices. 5 In addition to the technological importance, knowledge of cross-plane thermal conductivity of thin films and superlattices is also crucial for studying heat conduction at nanoscale. 6 For example, measurements of cross-plane thermal conductivity of superlattices advance our knowledge of heat transfer by coherent and incoherent phonons across superlattices.…”

Magnetocaloric effect and temperature coefficient of resistance of La0.85Ag0.15MnO3epitaxial thin films obtained by polymer-assisted deposition

“…There has been an increase in the demand for localized cooling and temperature stabilization of micro and optoelectronic devices [1][2][3] since (i) the number of components in an integrated circuit continues to increase, and (ii) modern devices demand ever smaller chips at an accelerated pace. The manufacture of micro-systems using magnetic refrigeration technology seems to be a promising alternative for thermo-electric microcooler applications [3,4].…”