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Device-level simulation capabilities have been developed to investigate low-frequency noise behavior in p-type Si0.7Ge0.3/Si heterostructure MOS (SiGe p-HMOS) transistors. The numerical model is based on the impedance field method; it accounts for a trap-induced carrier number fluctuation, a layer-dependent correlated mobility fluctuation, and a Hooge mobility fluctuation in the buried and parasitic surface channels, respectively. Simulations based on such models have been conducted for SiGe p-HMOS transistors, and the results have been carefully correlated with experimental data. Quantitative agreement has been obtained in terms of the noise level dependence on gate biases, drain currents, and body biases, revealing the important role of the dual channels in the low-frequency noise behavior of SiGe p-HMOS devices. [ABSTRACT FROM AUTHOR]

Temperature measurements have been made on Gunn diode samples, using both infrared (IR) and micro-Raman spectroscopy. Micro-Raman spectroscopy was used to give high-resolution temperature measurements on the active transit region of the Gunn diode. These were directly compared with IR thermal measurements made across the mesa region and also on the metallized top contact of the diode. [ABSTRACT FROM AUTHOR]

effects of the nonequilibrium population of optical phonon (hot-phonon effect) and acoustic phonon (self-heating effect) on the dc performance of carbon nanotube (CNT) MOSFET are examined by solving coupled semiclassical electron and phonon transport equations. In this paper, the numerical solution of these coupled transport equations is described. Full-band electron and phonon Boltzmann transport equations are solved to simulate the electron and phonon transport. Electron-phonon scattering rates are calculated using the tight-binding approach and the phonon-phonon scattering by relaxation time approximation (optical phonon relaxation time extracted by fitting the measured data of metallic tube). We show that the dc ballisticity of a CNT MOSFET degrades by approximately 10% due to hot-phonon effects, which is a much smaller degradation compared to two-terminal measurement of metallic tubes. Self-heating of the tube is also examined and is found to be insignificant for a single-tube transistor. [ABSTRACT FROM AUTHOR]

We present a detailed treatment of dissipative quantum transport in carbon-nanotube field-effect transistors (CNTFETs) using the nonequilibrium Green's function formalism. The effect of phonon scattering on the device characteristics of CNTFETs is explored using extensive numerical simulation. Both intra- and intervalley scattering mediated by acoustic (AP), optical (OP), and radial-breathing-mode (RBM) phonons are treated. Realistic phonon dispersion calculations are performed using force-constant methods, and electron-phonon coupling is determined through microscopic theory. Specific simulation results are presented for (16,0), (19,0), and (22,0) zigzag CNTFETs, which are in the experimentally useful diameter range. We find that the effect of phonon scattering on device performance has a distinct bias dependence. Up to moderate gate biases, the influence of high-energy OP scattering is suppressed, and the device current is reduced due to elastic backscattering by AP and low-energy RBM phonons. At large gate biases, the current degradation is mainly due to high-energy OP scattering. The influence of both AP and high-energy OP scattering is reduced for larger diameter tubes. The effect of RBM mode, however, is nearly independent of the diameter for the tubes studied here. [ABSTRACT FROM AUTHOR]

Simulations of the temperature field in silicon-on-insulator (SOI) and strained-Si transistors can benefit from experimental data and modeling of the thin silicon layer thermal conductivity at high temperatures. This paper develops algebraic expressions to account for the reduction in thermal conductivity due to the phonon-boundary scattering for pure and doped silicon layers and presents the experimental data for 50-nm-thick single-crystal silicon layers at high temperatures. The model applies to the temperature range of 300–1000 K for silicon layer thicknesses from 10 nm to 1 pm (and even bulk), which agrees well with the experimental data. In addition, the algebraic model has an excellent agreement with both the experimental data and predictions of thin-film thermal conductivity based on thermal conductivity integral and Boltzmann transport equation. The analytical thermal modeling and ISE-TCAD electrothermal simulations confirm that both the electrical and thermal performances of SOI transistor can be largely affected if the reduced thermal conductivity of the silicon due to phonon boundary scattering is not properly taken into consideration. [ABSTRACT FROM AUTHOR]

In this paper, we have extensively investigated the silicon thickness dependence of the low field electron mobility in ultrathin silicon-on-insulator (UT-SOI) MOSFETs operated both in single- and in double-gate mode. A physically based model including all the scattering mechanisms that are known to be most relevant in bulk MOSFETs has been extended and applied to SOI structures. A systematic comparison with the measurements shows that the experimental mobility dependence on the silicon thickness (T[subSI]) cannot be quantitatively explained within the transport picture that seems adequate for bulk transistors. In an attempt to improve the agreement with the experiments, we have critically rediscussed our model for the phonon scattering and developed a model for the scattering induced by the T[subSI] fluctuations. Our results suggest that the importance of the surface optical (SO) phonons could be significantly enhanced in UT-SOI MOSFETs with respect to bulk transistors. Furthermore, both the SO phonon and the T[subSI] fluctuation scattering are remarkably enhanced with reducing T[subSI], so that they could help explain the experimental mobility behavior. [ABSTRACT FROM AUTHOR]

This paper investigates the temperature dependence of phonon-scattering-limited mobility \muPH for advanced shortchannel strained pMOS devices. By using the split CV method and Matthiessen's rule, surface-roughness-limited mobility \muSR and \muPH are successfully decoupled. This paper indicates that the temperature sensitivity of \muPH is proportional to T^-1.75 for a neutral stressor and becomes higher when compressive strain is applied. It is explained by the higher optical phonon energy induced by uniaxially compressive strain. Our new findings may also explain the previously reported higher temperature sensitivity of drain current present in uniaxial strained pMOSFETs. [ABSTRACT FROM AUTHOR]

Shows that considering a small warping parabolic heavy hole model with the quasi-elastic approximation in the acoustic phonon scattering, the hole scattering length can be modeled to be independent of the hole energy. Information on the model; Discussion; Conclusions.

The comment adds the results of $2\times 2$ TSVs which is an extension of our 2-TSV case, and the clarification of no thermal strain effect on mobility. There are no contradictions with our original paper at all. Note that for the mobility calculation, the temperature dependence can be considered by the band parameters and phonon scattering [1]. [ABSTRACT FROM AUTHOR]