vestiftИзвестия Национальной академии наук Беларуси. Серия физико-технических наукProceedings of the National Academy of Sciences of Belarus. Physical-technical series1561-83582524-244XThe Republican Unitary Enterprise Publishing House "Belaruskaya Navuka"10.29235/1561-8358-2022-67-3-285-297vestift-753Research ArticleЭНЕРГЕТИКА, ТЕПЛО- И МАССООБМЕНPOWER ENGINEERING, HEAT AND MASS TRANSFERТеплопроводность нитрида галлия с кристаллической структурой типа вюрцитаThermal conductivity of wurtzite gallium nitridehttps://orcid.org/0000-0001-6942-810XВолчёкВ. С.VolcheckV. S.

Волчёк Владислав Сергеевич, научный сотрудник

ул. П. Бровки, 6, 220013, Минск

Vladislav S. Volcheck, Researcher

6, P. Brovka Str., 220013, Minsk

https://orcid.org/0000-0002-2618-4464БарановаМ. С.BaranavaM. S.

Баранова Мария Сергеевна, научный сотрудник

ул. П. Бровки, 6, 220013, Минск

Maryia S. Baranava, Researcher

6, P. Brovka Str., 220013, Minsk

https://orcid.org/0000-0001-9362-7539СтемпицкийВ. Р.StempitskyV. R.

Стемпицкий Виктор Романович, кандидат  технических наук, доцент, проректор по научной  работе, начальник научно-исследовательской части

ул. П. Бровки, 6, 220013, Минск

Viktor R. Stempitsky, Ph. D. (Engineering), Associate Professor, Vice-Rector for Research and Development, Head of Research and Development Department,

6, P. Brovka Str., 220013, Minsk

Белорусский государственный университет информатики и радиоэлектроникиBelarusian State University of Informatics and Radioelectronics202208102022673285297Copyright © Волчёк В.С., Баранова М.С., Стемпицкий В.Р., 20222022Волчёк В.С., Баранова М.С., Стемпицкий В.Р.Volcheck V.S., Baranava M.S., Stempitsky V.R.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://vestift.belnauka.by/jour/article/view/753

Выполнен анализ теоретических и экспериментальных исследований одного из важнейших параметров нитрида галлия с кристаллической структурой типа вюрцита – теплопроводности. Так как перенос тепла в нитриде галлия осуществляется главным образом с помощью фононов, его теплопроводность имеет температурную зависимость, характерную для большинства неметаллических кристаллов: увеличивается пропорционально третьей степени температуры в области низких температур, достигает своего максимального значения при температуре, приблизительно равной 1/20 от дебаевской, и уменьшается пропорционально температуре в области высоких температур. Показано, что в зависимости от условий (технология изготовления образца, кристаллографическое направление, концентрация примеси и других дефектов, изотопный состав) теплопроводность нитрида галлия может находиться в большом диапазоне значений, что указывает на важность определения этого параметра именно тех образцов материала, которые используются в конкретных приложениях. Теплопроводность нелегированного изотопно-чистого нитрида галлия при комнатной температуре оценивается на уровне 5,4 Вт/(см·К). Максимальная теплопроводность, достигнутая для объемного образца из монокристаллического нитрида галлия, равна 2,79 Вт/(см·К).

This paper reviews the theoretical and experimental works concerning one of the most important parameters of wurtzite gallium nitride – thermal conductivity. Since the heat in gallium nitride is transported almost exclusively by phonons, its thermal conductivity has a temperature behavior typical of most nonmetallic crystals: the thermal conductivity increases proportionally to the third power of temperature at lower temperatures, reaches its maximum at approximately 1/20 of the Debye temperature and decreases proportionally to temperature at higher temperatures. It is shown that the thermal conductivity of gallium nitride (depending on fabrication process, crystallographic direction, concentration of impurity and other defects, isotopical purity) varies significantly, emphasizing the importance of determining this parameter for the samples that closely resemble those being used in specific applications. For isotopically pure undoped wurtzite gallium nitride, the thermal conductivity at room temperature has been estimated as high as 5.4 W/(cm·K). The maximum room temperature value measured for bulkshaped samples of single crystal gallium nitride has been 2.79 W/(cm·K).

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The authors declare that there are no conflicts of interest present.