High-field charge transport and noise in p-Si from first principles

Article

关键词: BAND MONTE-CARLO;    DRIFT VELOCITY;    HOLE TRANSPORT;    ELECTRIC-FIELD;    DIFFUSION-COEFFICIENT;    ENERGY RELAXATION;    HOT HOLES;    SILICON;    TEMPERATURE;    GERMANIUM;   

DOI  :  10.1103/PhysRevB.107.035201

来源: SCIE

【 摘 要 】

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 paper highlights the use of high-field transport and noise properties as a rigorous test of the theory of electron-phonon interactions in semiconductors.

【 授权许可】

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