论文标题
首先原理中P-SI中的高场电荷运输和噪声
High-field charge transport and noise in p-Si from first principles
论文作者
论文摘要
由于电子相互作用的AB-Initio描述，半导体的电荷传输属性的无参数计算现在是常规的。许多研究集中于低场制度，其中载体温度等于晶格温度和当前功率谱密度（PSD）与迁移率成正比。由于这些关系不再存在，因此高场运输和噪声特性的计算对理论进行了更严格的检验，但很少有这样的计算。在这里，我们从第一原理中计算出77和300 K的最高原理以及沿各种晶体学轴沿着20 kV cm $^{ - 1} $的电场的高场迁移率和硅的高孔。我们发现这些计算定量再现了实验趋势，包括孔迁移率和PSD的各向异性和电场依赖性。还可以正确预测实验观察到的能量松弛时间与电场在电场下的快速变化。然而，与低场研究一样，绝对定量一致性通常缺乏，这是由于计算出的价带结构中不准确的差异。我们的工作强调了将高场传输和噪声特性用作半导体中电子相互作用理论的严格检验。
The parameter-free computation of charge transport properties of semiconductors is now routine owing to advances in the ab-initio description of the electron-phonon interaction. Many studies focus on the low-field regime in which the carrier temperature equals the lattice temperature and the current power spectral density (PSD) is proportional to the mobility. The calculation of high-field transport and noise properties offers a stricter test of the theory as these relations no longer hold, yet few such calculations have been reported. Here, we compute the high-field mobility and PSD of hot holes in silicon from first principles at temperatures of 77 and 300 K and electric fields up to 20 kV cm$^{-1}$ along various crystallographic axes. We find that the calculations quantitatively reproduce experimental trends including the anisotropy and electric-field dependence of hole mobility and PSD. The experimentally observed rapid variation of energy relaxation time with electric field at cryogenic temperatures is also correctly predicted. However, as in low-field studies, absolute quantitative agreement is in general lacking, a discrepancy that has been attributed to inaccuracies in the calculated valence band structure. Our work highlights the use of high-field transport and noise properties as a rigorous test of the theory of electron-phonon interactions in semiconductors.
