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The electronics packaging community strongly believes that Moore’s law will continue for another few years due to recent technological efforts to build heterogeneously integrated packages. Heterogeneous integration (HI) can be at the chip level (a single chip with multiple hotspots), in multi-chip modules, or in vertically stacked three-dimensional (3D) integrated circuits. Flux values have increased exponentially with a simultaneous reduction in chip size and a significant increase in performance, leading to increased heat dissipation. The electronics industry and the academic research community have examined various solutions to tackle skyrocketing thermal-management challenges. Embedded cooling eliminates most sequential conduction resistance from the chip to the ambient, unlike separable cold plates/ heat sinks. Although embedding the cooling solution onto an electronic chip results in a high heat transfer potential, technological risks and complexity are still associated with the implementation of these technologies and with uncertainty regarding which technologies will be adopted. This manuscript discusses recent advances in embedded cooling, fluid selection considerations, and conventional, immersion, and additive manufacturing-based embedded cooling technologies.
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Silicon Microthermoelectric Coolers for Local Heat Removal in Integrated Circuit Chips
Advancements in electronic device fabrication with increasing integration levels have resulted in very high device densities. This has led to higher power dissipation and heat fluxes, increasing integrated circuit (IC) operating temperature. High and nonuniform heat generation degrades device and system performance. Therefore, thermal management to keep ICs within prescribed temperature limits is an important challenge for reliable and economic performance. Cooling techniques, including liquid coolants and air conditioning (AC), have been utilized to remove heat at the package and system level. However, these techniques must overcome high thermal impedances and require complex integration, while global cooling is generally wasteful, inefficient, and expensive. To improve thermal management, we have developed Si microthermoelectric coolers (μTECs) with areas as small 1E−5 cm^2 that can be integrated on -chip near local hot spots using the standard fabrication processes. While Si μTECs cannot achieve low base temperatures, they can actively pump relatively high heat fluxes directly to a heat sink, thus reducing local temperature increases and allowing targeted rather than global waste heat removal. We demonstrate μTECs that can pump up to 43 W/cm^2 of locally generated excess heat with no increase in chip temperature.
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- Award ID(s):
- 2206888
- PAR ID:
- 10504755
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- IEEE transactions on electron devices
- ISSN:
- 0018-9383
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1109/TED.2023.3304277
