SUMMARY:
Researchers in the Department of Mechanical and Aerospace Engineering at UCLA have developed a thermal interface for electronic devices that has highly desirable thermal conductivity and excellent elastic compliance.
BACKGROUND:
Electronic devices, such as smart phones and laptops, generate waste heat that must be dissipated to prevent performance degradation and decreased device efficiency. Since the heat must often be transferred through multilayered devices and heterogenous interfaces, materials with high thermal conductivity and enhanced thermal coupling are required for efficient heat dissipation. However, there is a tradeoff between a material’s high thermal conductivity and the soft mechanics that enable its enhanced thermal coupling. Strongly bonded materials, such as ceramics and dielectrics, usually have high thermal conductivity, but their rigid structure can potentially lead to delamination, cracking, and void formation. On the other hand, conventional soft materials, such as polymers, can conform to interfaces effectively but are limited by their intrinsically low thermal conductivity. Therefore, there is a strong demand for an interface that has a high thermal conductivity but is sufficiently soft and flexible for enhanced thermal coupling.
INNOVATION:
Researchers at in the Department of Mechanical and Aerospace Engineering at UCLA have developed a thermal interface material that not only has a high thermal conductivity of 21 W/m·K, but also has excellent elastic compliance similar to that of biological tissues at 100 kPa. The interfacial material can maintain its thermal conductivity after 500 bending cycles. The technology is based on self-assembled manufacturing of cubic boron arsenide. It is a promising advancement for thermal management materials used in soft and flexible devices as well as in conventional electronics, and holds value for future applications in wearable electronics and soft robotics.
POTENTIAL APPLICATIONS:
- Thermal management for electronic, optoelectronic, and photonic devices
- Flexible thermal conductor for wearable electronics and soft robotics
ADVANTAGES:
- High thermal conductivity
- Enhanced thermal coupling
- Low elastic modulus similar to that of biological tissue
- Flexible
- Maintains performance after 500 bending cycles
DEVELOPMENT-TO-DATE:
Reduced to practice in laboratory environment
RELATED PAPERS:
Kang, J. S.; Li, M.; Wu, H.; Nguyen, H.; Aoki, T.; Hu, Y. Integration of Boron Arsenide Cooling Substrates into Gallium Nitride Devices. Nat. Electron. 2021, 4 (6), 416–423. https://doi.org/10.1038/s41928-021-00595-9.
Cui, Y.; Qin, Z.; Wu, H.; Li, M.; Hu, Y. Flexible Thermal Interface Based on Self-Assembled Boron Arsenide for High-Performance Thermal Management. Nat. Commun. 2021, 12 (1), 1–7. https://doi.org/10.1038/s41467-021-21531-7.