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Abstract Thermal metamaterials exhibit thermal properties that do not exist in nature but can be rationally designed to offer unique capabilities of controlling heat transfer. Recent advances have demonstrated successful manipulation of conductive heat transfer and led to novel heat guiding structures such as thermal cloaks, concentrators, etc. These advances imply new opportunities to guide heat transfer in complex systems and new packaging approaches as related to thermal management of electronics. Such aspects are important, as trends of electronics packaging toward higher power, higher density, and 2.5D/3D integration are making thermal management even more challenging. While conventional cooling solutions based on large thermal-conductivity materials as well as heat pipes and heat exchangers may dissipate the heat from a source to a sink in a uniform manner, thermal metamaterials could help dissipate the heat in a deterministic manner and avoid thermal crosstalk and local hot spots. This paper reviews recent advances of thermal metamaterials that are potentially relevant to electronics packaging. While providing an overview of the state-of-the-art and critical 2.5D/3D-integrated packaging challenges, this paper also discusses the implications of thermal metamaterials for the future of electronic packaging thermal management. Thermal metamaterials could provide a solution to nontrivial thermal management challenges. Future research will need to take on the new challenges in implementing the thermal metamaterial designs in high-performance heterogeneous packages to continue to advance the state-of-the-art in electronics packaging.
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Thermal Conductivity of Protein-Based Materials: A Review
Fibrous proteins such as silks have been used as textile and biomedical materials for decades due to their natural abundance, high flexibility, biocompatibility, and excellent mechanical properties. In addition, they also can avoid many problems related to traditional materials such as toxic chemical residues or brittleness. With the fast development of cutting-edge flexible materials and bioelectronics processing technologies, the market for biocompatible materials with extremely high or low thermal conductivity is growing rapidly. The thermal conductivity of protein films, which is usually on the order of 0.1 W/m·K, can be rather tunable as the value for stretched protein fibers can be substantially larger, outperforming that of many synthetic polymer materials. These findings indicate that the thermal conductivity and the heat transfer direction of protein-based materials can be finely controlled by manipulating their nano-scale structures. This review will focus on the structure of different fibrous proteins, such as silks, collagen and keratin, summarizing factors that can influence the thermal conductivity of protein-based materials and the different experimental methods used to measure their heat transfer properties.
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- Award ID(s):
- 1809541
- PAR ID:
- 10092307
- Date Published:
- Journal Name:
- Polymers
- Volume:
- 11
- Issue:
- 3
- ISSN:
- 2073-4360
- Page Range / eLocation ID:
- 456
- 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/10.3390/polym11030456
