Abstract In contrast to known Raman-thermometric measurements of thermal conductivity (k) of suspended Si nano-membranes, here we apply Raman thermometry for k measurement of mono- and nano-crystalline Si films on quartz, which is important for applications in thermoelectricity and nanoelectronics. Experimentally, we measure linear dependence of the laser-induced Raman band downshift, which is proportional to the moderate heating ΔT, on the laser power P. Then we convert the downshift to ΔT and determine the ratio ΔT/P. The actual power absorbed by the film is calculated theoretically and controlled experimentally by the reflection/transmission measurement. Then we calculate ΔTcalc/P for arbitrary film k assuming diffusive phonon transport (DPT). Film k is determined from the condition ΔT/P = ΔTcalc/P. We show that this method works well for films with thickness h > Λ, where Λ is phonon-mean-free path, even for low-k films like nano-crystalline Si and SiGe. For h

中文翻译：

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一种使用拉曼测温法测量纳米薄膜体基热导率的简单有效方法

摘要 与已知的悬浮硅纳米膜热导率 (k) 的拉曼测温测量不同，这里我们应用拉曼测温测量石英上的单晶和纳米晶硅膜的 k 测量，这对于热电和热电领域的应用很重要。纳米电子学。通过实验，我们测量了激光诱导的拉曼带降移对激光功率 P 的线性相关性，这与适度加热 ΔT 成正比。然后我们将降档转换为 ΔT 并确定比率 ΔT/P。薄膜吸收的实际功率是从理论上计算出来的，并通过反射/透射测量进行实验控制。然后我们计算任意薄膜 k 的 ΔTcalc/P 假设扩散声子传输 (DPT)。薄膜 k 由条件 ΔT/P = ΔTcalc/P 确定。我们表明，这种方法适用于厚度 h > Λ 的薄膜，其中 Λ 是无声子平均路径，甚至适用于纳米晶 Si 和 SiGe 等低 k 薄膜。对于 h