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Conductividad térmica ultraalta en nitruro cúbico de boro enriquecido con isótopos

Ke Chen¹, Bai Song², Navaneetha K Ravichandran³

¹Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.

Science (New York, N.Y.)

|January 11, 2020

Resumen

Los cristales de nitruro de boro cúbico (cBN) con isótopos de boro enriquecidos presentan una conductividad térmica muy alta (κ) superior a 1600 W/m·K. Este descubrimiento pone de relieve cBN

Área de la Ciencia:

Ciencias de los materiales
Física del estado sólido
Crecimiento cristalino

Sus antecedentes:

Los materiales de alta conductividad térmica (κ) son cruciales para los avances tecnológicos y la comprensión científica fundamental.
La composición isotópica influye significativamente en las propiedades del material, incluido el transporte térmico.

Objetivo del estudio:

Investigar el impacto del enriquecimiento de isótopos de boro en la conductividad térmica del nitruro de boro cúbico (cBN).
Para comparar la mejora isotópica de κ en cBN con otros compuestos a base de boro como el fosfuro de boro y el arseniuro de boro.
Evaluar el potencial del cBN para aplicaciones electrónicas y optoelectrónicas avanzadas.

Principales métodos:

Crecimiento de cristales de nitruro de boro cúbico (cBN) con abundancia controlada de isótopos de boro (¹⁰B y ¹¹B).
Medición de la conductividad térmica (κ) a temperatura ambiente para muestras de cBN enriquecidas isotópicamente.
Análisis comparativo de los efectos isotópicos en el cBN, el fosfuro de boro y el arseniuro de boro.

Principales resultados:

Se obtiene una conductividad térmica ultraalta (κ) superior a 1600 vatios por metro-kelvin en cBN enriquecido isotópicamente a temperatura ambiente.
Se observó una mejora isotópica significativamente menor de κ en el fosfuro de boro y el arseniuro de boro en comparación con el cBN.
Se ha demostrado que el desorden de masa isotópica tiene un efecto reducido en los fonones del fosfuro de boro y del arseniuro de boro.

Conclusiones:

El cBN de ingeniería isotópica exhibe una conductividad térmica excepcional, superando la de muchos materiales establecidos.
El amplio espacio de banda (6,2 eV) de cBN, combinado con su κ ultraalto, lo posiciona como un candidato líder para la gestión térmica en microelectrónica.
cBN tiene una promesa significativa para aplicaciones electrónicas y optoelectrónicas de alta potencia que requieren un rendimiento térmico superior.

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