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Title: Ultrahigh thermal conductivity in isotope-enriched cubic boron nitride

Materials with high thermal conductivity (κ) are of technological importance and fundamental interest. We grew cubic boron nitride (cBN) crystals with controlled abundance of boron isotopes and measured κ greater than 1600 watts per meter-kelvin at room temperature in samples with enriched10B or11B. In comparison, we found that the isotope enhancement of κ is considerably lower for boron phosphide and boron arsenide as the identical isotopic mass disorder becomes increasingly invisible to phonons. The ultrahigh κ in conjunction with its wide bandgap (6.2 electron volts) makes cBN a promising material for microelectronics thermal management, high-power electronics, and optoelectronics applications.

 
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Award ID(s):
1851052
NSF-PAR ID:
10132599
Author(s) / Creator(s):
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Publisher / Repository:
American Association for the Advancement of Science (AAAS)
Date Published:
Journal Name:
Science
Volume:
367
Issue:
6477
ISSN:
0036-8075
Page Range / eLocation ID:
p. 555-559
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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