المؤلفون: Iglesias, Jose Manuel, Nardone, Alejandra, Rengel, Raul, Kalna, Karol, Martin, Maria J., Pascual, Elena

المصدر: 2D Materials, 14, 025011 (2023)

مصطلحات موضوعية: Physics - Applied Physics, Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Materials Science

الوصف: The effect of degeneracy and the impact of free-carrier screening on a low-field mobility and a high-field drift velocity in MoS2 and WS2 are explored using an in-house ensemble Monte Carlo simulator. Electron low field mobility increases to 8400 cm2/Vs for MoS2 and to 12040 cm2/Vs for WS2 when temperature decreases to 77 K and carrier concentration is around 5e12 cm-2. In the case of holes, best mobility values were 9320 cm2/Vs and 13290 cm2 per Vs, reached at 77 K, while at room temperature these fall to 80 cm2/Vs and 150 cm2/Vs for MoS2 and WS2, respectively. The carrier screening effect plays a major role at low fields, and low and intermediate temperatures, where a combination of large occupancy of primary valleys and carrier-phonon interactions dominated by relatively low energy exchange processes results in an enhanced screening of intrinsic scattering. For electrons, degeneracy yields to transport in secondary valleys, which plays an important role in the decrease of the low field mobility at high concentrations and/or at room temperature. The high-field drift velocity is not much affected by carrier screening because of an increased carrier scattering with surface optical polar phonons, favouring larger phonon wavevector interactions with small dielectric function values.
Comment: 10 pages, 5 figures. Published in 2D Materials, 14, 025011 (2023)

الوصول الحر: http://arxiv.org/abs/2402.07835Test

المؤلفون: Iglesias, José M, Nardone, Alejandra, Rengel, Raúl, Kalna, Karol, Martín, María J, Pascual, Elena

المصدر: 2D Materials ; volume 10, issue 2, page 025011 ; ISSN 2053-1583

الوصف: The effect of degeneracy and the impact of free-carrier screening on a low-field mobility and a high-field drift velocity in MoS 2 and WS 2 are explored using an in-house ensemble Monte Carlo simulator. Electron low field mobility increases to 8400 c m 2 V − 1 s − 1 for MoS 2 and to 12 040 c m 2 V − 1 s − 1 for WS 2 when temperature decreases to 77 K and carrier concentration is around 5 × 10 12 c m − 2 . In the case of holes, best mobility values were 9 320 c m 2 V − 1 s − 1 and 13 290 c m 2 V − 1 s − 1 , reached at similar temperature and carrier concentration conditions while at room temperature these fall to 80 c m 2 V − 1 s − 1 and 150 c m 2 V − 1 s − 1 for MoS 2 and WS 2 , respectively. The carrier screening effect plays a major role at low fields, and low and intermediate temperatures, where a combination of large occupancy of primary valleys and carrier–phonon interactions dominated by relatively low energy exchange processes results in an enhanced screening of intrinsic scattering. For electrons, degeneracy yields to transport in secondary valleys, which plays an important role in the decrease of the low field mobility at high concentrations and/or at room temperature. The high-field drift velocity is not much affected by carrier screening because of an increased carrier scattering with surface optical polar phonons, favouring larger phonon wavevector interactions with small dielectric function values.

الإتاحة: https://doi.org/10.1088/2053-1583/acb1c2Test