Aluminum scandium nitride (Al_1-xSc_xN) is regarded as a promising material for high-performance acoustic devices used in wireless communication systems. Phonon scattering and heat conduction processes govern the energy dissipation in acoustic resonators, ultimately determining their performance quality. This work reports on phonon scattering processes and thermal conductivity in Al_1-xSc_xN alloys grown by molecular beam epitaxy with the Sc content (x) up to 0.26. The thermal conductivity shows a descending trend with increasing Sc content. Temperature-dependent measurements show an increase in thermal conductivity as the temperature increases at temperatures below 200 K, followed by a plateau at higher temperatures (T > 200 K). Application of an analytical Debye-Callaway model allows us to estimate the effects of boundary and alloy scattering on the observed thermal conductivity behavior. This work provides insight for phonon scattering mechanisms and the resultant thermal conductivity in Al_1-xSc_xN, paving the way for future investigation of materials and design of acoustic devices.

氮化铝钪 (Al _1-x Sc _x N) 被认为是用于无线通信系统的高性能声学器件的有前途的材料。声子散射和热传导过程控制着声谐振器的能量耗散，最终决定了它们的性能质量。这项工作报告了 Al _1-x Sc _{x 中的}声子散射过程和热导率通过分子束外延生长的 N 合金，Sc 含量 (x) 高达 0.26。随着Sc含量的增加，热导率呈下降趋势。温度相关测量表明，随着温度在低于 200 K 时升高，热导率会增加，然后在较高温度 (T > 200 K) 时趋于平稳。分析性 Debye-Callaway 模型的应用使我们能够估计边界和合金散射对观察到的热导率行为的影响。这项工作为 Al _1-x Sc _x N 中的声子散射机制和由此产生的热导率提供了见解，为未来材料研究和声学器件设计铺平了道路。