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】
Free