论文标题
载流子迁移率的温度依赖性不是主要的散射机制的可靠指标
The temperature-dependence of carrier mobility is not a reliable indicator of the dominant scattering mechanism
论文作者
论文摘要
实验荷载载流子迁移率的温度依赖性通常用作半导体中主要载体散射机制的预测指标，尤其是在热电应用中。在这项工作中，我们批判性地评估了这种做法是否有充分的基础。对47个最先进的迁移率计算的综述表明，主要散射机制与迁移率的温度趋势之间没有相关性。取而代之的是，我们证明了声子频率是温度依赖性背后的主要驱动力，并且甚至对于理想化的材料而言，也可能在$ t^{ - 1} $之间变化。为了证明这一点，我们计算了23,000材料的迁移率，并审查了它们的温度依赖性，包括将贡献与变形，极性和杂质散射机制分开。我们最终证明了$ t^{ - 1.5} $的温度依赖性不是变形电位散射的可靠指标。我们的工作突出了仅基于实验迁移率温度趋势来预测主要散射类型的潜在陷阱。
The temperature dependence of experimental charge carrier mobility is commonly used as a predictor of the dominant carrier scattering mechanism in semiconductors, particularly in thermoelectric applications. In this work, we critically evaluate whether this practice is well founded. A review of 47 state-of-the-art mobility calculations reveals no correlation between the major scattering mechanism and the temperature trend of mobility. Instead, we demonstrate that the phonon frequencies are the prevailing driving forces behind the temperature dependence and can cause it to vary between $T^{-1}$ to $T^{-3}$ even for an idealised material. To demonstrate this, we calculate the mobility of 23,000 materials and review their temperature dependence, including separating the contributions from deformation, polar, and impurity scattering mechanisms. We conclusively demonstrate that a temperature dependence of $T^{-1.5}$ is not a reliable indicator of deformation potential scattering. Our work highlights the potential pitfalls of predicting the major scattering type based on the experimental mobility temperature trend alone.
