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Abstract High thermal conductivity electronic materials are critical components for high-performance electronic and photonic devices as both active functional materials and thermal management materials. We report an isotropic high thermal conductivity exceeding 500 W m −1 K −1 at room temperature in high-quality wafer-scale cubic silicon carbide (3C-SiC) crystals, which is the second highest among large crystals (only surpassed by diamond). Furthermore, the corresponding 3C-SiC thin films are found to have record-high in-plane and cross-plane thermal conductivity, even higher than diamond thin films with equivalent thicknesses. Our results resolve a long-standing puzzle that the literature values of thermal conductivity for 3C-SiC are lower than the structurally more complex 6H-SiC. We show that the observed high thermal conductivity in this work arises from the high purity and high crystal quality of 3C-SiC crystals which avoids the exceptionally strong defect-phonon scatterings. Moreover, 3C-SiC is a SiC polytype which can be epitaxially grown on Si. We show that the measured 3C-SiC-Si thermal boundary conductance is among the highest for semiconductor interfaces. These findings provide insights for fundamental phonon transport mechanisms, and suggest that 3C-SiC is an excellent wide-bandgap semiconductor for applications of next-generation power electronics as both active components and substrates.
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This content will become publicly available on February 24, 2026
High-yield growth of high-quality cubic BAs single crystals using the Bridgman method
The increasing complexity of semiconductor devices fabricated from wide-bandgap and ultra-wide-bandgap materials demand advanced thermal management solutions to mitigate heat buildup, a major cause of device failure. High thermal conductivity materials are thus becoming crucial for thermal management. Cubic boron arsenide (c-BAs) has emerged as a promising candidate. However, challenges remain in synthesizing high-quality crystals with low defect concentrations, high homogeneous thermal conductivity, and high yields using the conventional chemical vapor transport method. In this study, we report the synthesis of high-yield c-BAs single crystals using the Bridgman method. The crystals exhibit high uniformity, reduced defect densities, and lower carrier concentrations as confirmed through x-ray diffraction, Raman spectroscopy, temperature-dependent photoluminescence, and electrical transport measurements. Our work represents a significant step toward scalable production of high-quality c-BAs for industrial applications, offering a practical solution for improving thermal management in next-generation electronic devices.
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- Award ID(s):
- 2329110
- PAR ID:
- 10630415
- Publisher / Repository:
- AIP
- Date Published:
- Journal Name:
- Applied Physics Letters
- Volume:
- 126
- Issue:
- 8
- ISSN:
- 0003-6951
- Page Range / eLocation ID:
- 082107
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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