TCAD Simulation of Dose Radiation Effects in Sub-100 nm High-k MOSFET Structures
The sub-100-nm CMOS process with a high-κ gate dielectric is one of the key technologies for the
fabrication of digital, analog, and RF VLSI circuits and on-chip systems. The influence of ionizing radiation
on 45-nm MOS transistors with a high-κ dielectric fabricated using the bulk-silicon and SOI technologies is
simulated. Effects induced by the substitution of SiO2 with a high-κ dielectric are noted. The processes of
selection and tuning of physical models for the simulation of high-κ MOS transistors in the Sentaurus TCAD
are outlined. A set of new physical semiempirical models introducing the dependence of radiation-sensitive
parameters (carrier lifetime, carrier mobility, charge density in the bulk of SiO2 and HfO2 and at the HfO2/Si
interfaces) on the irradiation dose is developed. Nanoscale bulk and SOI MOS transistors with a high-κ
dielectric are simulated. It is demonstrated that an increase in the drain current after irradiation in nanoscale
SOI structures is induced by the charge accumulation in the side oxide. An acceptable fit between the simulation
results and the experimental data is obtained. The simulation results confirm that the leakage current
is suppressed (compared to common MOS transistors with SiO2) in sub-100-nm MOS transistors with a
high-κ dielectric. However, the other important parameters of sub-100-nm MOS transistors with a high-κ
dielectric are more sensitive to ionizing radiation.
Quasi-3D model for calculation of radiation leakage currents in modern submicron SOI MOSFET structures is proposed. Instead of the fully 3D modeling is proposed to solve two tasks: 2D modeling of the traditional MOSFET cross-section and 3D modeling of the side parasitic transistor. The radiation-induced leakage current simulation in the 0.35 μm SOI MOSFET structure with taking account ionizing radiation with a dose of up to 500 krad was simulated. The results of the simulation show that in comparison with the traditional fully 3D modeling, which requires 11 hours of computer time, the computer time for the IdVg characteristic was reduced to 71 minutes (i.e. the computer time decreased by 9 times).
For the correct accounting of joint effects of radiation and temperature on characteristics of MOSFETs with the help of TCAD system the nonlinear correction coefficient which considers change of concentration of traps from temperature is entered into model of traps volume density in oxide.
Hardware-software system designed for automated SOI MOSFETs characteristics measurement, processing and SPICE model parameter extraction taking into account high temperature (HT) effects (to 300°C) is presented. The essence of the system is comprised of a set of selected measurement instru-ments, measurement and data processing methods with the pur-pose of SPICE model library creation in lightly manned condi-tions. This capability to program measurement conditions and data collection, processing and saving is realized with in-house LabVIEW virtual instruments.
Generalized error-locating codes are discussed. An algorithm for calculation of the upper bound of the probability of erroneous decoding for known code parameters and the input error probability is given. Based on this algorithm, an algorithm for selection of the code parameters for a specified design and input and output error probabilities is constructed. The lower bound of the probability of erroneous decoding is given. Examples of the dependence of the probability of erroneous decoding on the input error probability are given and the behavior of the obtained curves is explained.
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
Radiation conditions are described for various space regions, radiation-induced effects in spacecraft materials and equipment components are considered and information on theoretical, computational, and experimental methods for studying radiation effects are presented. The peculiarities of radiation effects on nanostructures and some problems related to modeling and radiation testing of such structures are considered.
This volume presents new results in the study and optimization of information transmission models in telecommunication networks using different approaches, mainly based on theiries of queueing systems and queueing networks .
The paper provides a number of proposed draft operational guidelines for technology measurement and includes a number of tentative technology definitions to be used for statistical purposes, principles for identification and classification of potentially growing technology areas, suggestions on the survey strategies and indicators. These are the key components of an internationally harmonized framework for collecting and interpreting technology data that would need to be further developed through a broader consultation process. A summary of definitions of technology already available in OECD manuals and the stocktaking results are provided in the Annex section.