Thermal conductivity of ScxAl1−xN and YxAl1−xN alloys
(2023) In Applied Physics Letters 122(18).- Abstract
Owing to their very large piezoelectric coefficients and spontaneous polarizations, (Sc,Y) x Al1−xN alloys have emerged as a new class of III-nitride semiconductor materials with great potential for high-frequency electronic and acoustic devices. The thermal conductivity of constituent materials is a key parameter for design, optimization, and thermal management of such devices. In this study, transient thermoreflectance technique is applied to measure the thermal conductivity of ScxAl1−xN and YxAl1−xN (0 ≤ x ≤ 0.22 ) layers grown by magnetron sputter epitaxy in the temperature range of 100-400 K. The room-temperature thermal conductivity of both alloys is found to decrease... (More)
Owing to their very large piezoelectric coefficients and spontaneous polarizations, (Sc,Y) x Al1−xN alloys have emerged as a new class of III-nitride semiconductor materials with great potential for high-frequency electronic and acoustic devices. The thermal conductivity of constituent materials is a key parameter for design, optimization, and thermal management of such devices. In this study, transient thermoreflectance technique is applied to measure the thermal conductivity of ScxAl1−xN and YxAl1−xN (0 ≤ x ≤ 0.22 ) layers grown by magnetron sputter epitaxy in the temperature range of 100-400 K. The room-temperature thermal conductivity of both alloys is found to decrease significantly with increasing Sc(Y) composition compared to that of AlN. We also found that the thermal conductivity of YxAl1−xN is lower than that of ScxAl1−xN for all studied compositions. In both alloys, the thermal conductivity increases with the temperature up to 250 K and then saturates. The experimental data are analyzed using a model based on the solution of the phonon Boltzmann transport equation within the relaxation time approximation. The contributions of different phonon-scattering mechanisms to the lattice thermal conductivity of (Sc,Y) x Al1−xN alloys are identified and discussed.
(Less)
- author
- Tran, Dat Q. ; Tasnádi, Ferenc ; Žukauskaitė, Agnė ; Birch, Jens ; Darakchieva, Vanya LU and Paskov, Plamen P.
- organization
- publishing date
- 2023-05-01
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Applied Physics Letters
- volume
- 122
- issue
- 18
- article number
- 182107
- publisher
- American Institute of Physics (AIP)
- external identifiers
-
- scopus:85158020755
- ISSN
- 0003-6951
- DOI
- 10.1063/5.0145847
- language
- English
- LU publication?
- yes
- id
- d3d5eae2-97df-43c9-86bd-0b488c7faff6
- date added to LUP
- 2023-08-11 10:34:02
- date last changed
- 2023-11-08 08:30:27
@article{d3d5eae2-97df-43c9-86bd-0b488c7faff6, abstract = {{<p>Owing to their very large piezoelectric coefficients and spontaneous polarizations, (Sc,Y) x Al<sub>1−x</sub>N alloys have emerged as a new class of III-nitride semiconductor materials with great potential for high-frequency electronic and acoustic devices. The thermal conductivity of constituent materials is a key parameter for design, optimization, and thermal management of such devices. In this study, transient thermoreflectance technique is applied to measure the thermal conductivity of Sc<sub>x</sub>Al<sub>1−x</sub>N and Y<sub>x</sub>Al<sub>1−x</sub>N (0 ≤ x ≤ 0.22 ) layers grown by magnetron sputter epitaxy in the temperature range of 100-400 K. The room-temperature thermal conductivity of both alloys is found to decrease significantly with increasing Sc(Y) composition compared to that of AlN. We also found that the thermal conductivity of Y<sub>x</sub>Al<sub>1−x</sub>N is lower than that of Sc<sub>x</sub>Al<sub>1−x</sub>N for all studied compositions. In both alloys, the thermal conductivity increases with the temperature up to 250 K and then saturates. The experimental data are analyzed using a model based on the solution of the phonon Boltzmann transport equation within the relaxation time approximation. The contributions of different phonon-scattering mechanisms to the lattice thermal conductivity of (Sc,Y) x Al<sub>1−x</sub>N alloys are identified and discussed.</p>}}, author = {{Tran, Dat Q. and Tasnádi, Ferenc and Žukauskaitė, Agnė and Birch, Jens and Darakchieva, Vanya and Paskov, Plamen P.}}, issn = {{0003-6951}}, language = {{eng}}, month = {{05}}, number = {{18}}, publisher = {{American Institute of Physics (AIP)}}, series = {{Applied Physics Letters}}, title = {{Thermal conductivity of Sc<sub>x</sub>Al<sub>1−x</sub>N and Y<sub>x</sub>Al<sub>1−x</sub>N alloys}}, url = {{http://dx.doi.org/10.1063/5.0145847}}, doi = {{10.1063/5.0145847}}, volume = {{122}}, year = {{2023}}, }