| 1. |
- von Haartman, M., et al.
(författare)
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Impact of strain and channel orientation on the low-frequency noise performance of Si n- and pMOSFETs
- 2007
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Ingår i: Solid-State Electronics. - : Elsevier BV. - 0038-1101 .- 1879-2405. ; 51:5, s. 771-777
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Tidskriftsartikel (refereegranskat)abstract
- Mobility and low-frequency (LF) noise were studied in tensile strained Si n- and pMOSFETs fabricated on relaxed SiGe virtual substrates. Both the impact of the channel orientation ((110) or (100) on (100) Si) and the tensile strain were carefully investigated. Two types of virtual substrates were used; a thin relaxed SiGe layer (20% Ge) and a thick one (27% Ge). The strained Si nMOSFETs fabricated on the thin substrate showed similar LF noise level as in the reference devices, whereas the thick substrate caused severely increased LF noise in the nMOSFETs. The latter was linked to the higher Ge concentration and explained by possible misfit dislocations and increased defect densities, likely resulting from strain relaxation caused by ion implantation damage. On the other hand, considerably lower LF noise was achieved in the pMOSFETs on the thick SiGe. The channel orientation was not found to have a significant influence on the LF noise performance in any of the studied devices.
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| 2. |
- Donetti, L., et al.
(författare)
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Hole effective mass in silicon inversion layers with different substrate orientations and channel directions
- 2011
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Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 110:6, s. 063711-
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Tidskriftsartikel (refereegranskat)abstract
- We explore the possibility to define an effective mass parameter to describe hole transport in inversion layers in bulk MOSFETs and silicon-on-insulator devices. To do so, we employ an accurate and computationally efficient self-consistent simulator based on the six-band k . p model. The valence band structure is computed for different substrate orientations and silicon layer thicknesses and is then characterized through the calculation of different effective masses taking account of the channel direction. The effective masses for quantization and density of states are extracted from the computed energy levels and subband populations, respectively. For the transport mass, a weighted averaging procedure is introduced and justified by comparing the results with hole mobility from experiments and simulations.
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| 3. |
- Donetti, L., et al.
(författare)
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On the effective mass of holes in inversion layers
- 2011
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Ingår i: International Conference on Ultimate Integration on Silicon. - 9781457700903 ; , s. 50-53
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Konferensbidrag (refereegranskat)abstract
- We study hole inversion layers in bulk MOSFETs and silicon-on-insulator devices employing a self-consistent simulator based on the six-band kp model. Valence Band structure is computed for different device orientations and silicon layer thicknesses, and then it is characterized through the calculation of different effective masses.
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| 4. |
- Thomas, S. M., et al.
(författare)
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On the role of Coulomb scattering in hafnium-silicate gated silicon n and p-channel metal-oxide-semiconductor-field-effect-transistors
- 2011
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Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 110:12, s. 124503-
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Tidskriftsartikel (refereegranskat)abstract
- In this work, the impact of the local and remote Coulomb scattering mechanisms on electron and hole mobility are investigated. The effective mobilities in quasi-planar finFETs with TiN/Hf(0.4)Si(0.6)O/SiO(2) gate stacks have been measured at 300 K and 4 K. At 300 K, electron mobility is degraded below that of bulk MOSFETs in the literature, whereas hole mobility is comparable. The 4 K electron and hole mobilities have been modeled in terms of ionized impurity, local Coulomb, remote Coulomb and local roughness scattering. An existing model for remote Coulomb scattering from a polycrystalline silicon gate has been adapted to model remote Coulomb scattering from a high-kappa/SiO(2) gate stack. Subsequently, remote charge densities of 8 x 10(12) cm(-2) at the Hf(0.4)Si(0.6)O/SiO(2) interface were extracted and shown to be the dominant Coulomb scattering mechanism for both electron and hole mobilities at 4 K. Finally, a Monte Carlo simulation showed remote Coulomb scattering was responsible for the degraded 300 K electron mobility.
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