Query: element edge tcad

Candidate papers:

abstract: Technology computer aided design (TCAD) semiconductor device simulators solve partial differential equations (PDE) using the finite volume method (FVM) or related methods. While this approach has been in use over several decades, its methods continue to be extended, and are still applicable for investigating novel devices. In this paper, we present an element edge based (EEB) FVM discretization approach suitable for capturing vector field effects. Drawing from a 2D approach in the literature, we have extended this method to 3D. We implemented this method in a TCAD semiconductor device simulator, which uses a generalized PDE (GPDE) approach to simulate de vices with the FVM. We describe how our EEB method is compatible with the GPDE approach, allowing the modeling of vector effects using scripting. This method is applied to solve polarization effects in a 3D ferro capacitor, and a 2D ferroelectric field effect transistor. An example for field dependent mobility in a 3D MOSFET is also presented.
title: Element Edge Based Discretization for TCAD Device Simulation
venue: IEEE Transactions on Electron Devices
year: 2021

abstract: In this work, the magnitude of the electric field and the deple tion inside a simplified two dimensional model of the ATLAS planar pixel sensor for th e insertable b layer and the super LHC upgrade have been studied. The parameters influen cing the breakdown behavior were studied using a finite element method to solve the drift iffusion equations coupled to Poisson's equation. Using these models, the number of guard rings, dead edge width and sensor's thickness were modified with respect to the ATLAS ac tual pixel sensor to investigate their influence on the sensor's depletion at the edge and on its internal electrical field distribution. The goal of the simulation is to establish a mo del to discriminate between different designs and to select the most optimized to fit the need s in radiation hardness and low material budget of ATLAS inner detector during super LHC op eration. A three defects level model has been implemented in the simulations to study the be avior of such sensors under different level of irradiation. Using the results of our sim ulations, we propose guidelines for the design of future pixel sensor structures and propose test structures to be inserted in a wafer production to verify and calibrate our simulation mod el.
author_names: A Lounis

Dominique Martinot

Giovanni Calderini

Giovanni Marchiori

Mathieu Benoit

Nicoleta Dinu
title: TCAD Simulation of ATLAS Pixel Guard Ring and Edge Structure for Super LHC Upgrade
year: 2010

abstract: In this work, the magnitude of the electric field and the depletion inside a simplified two dimensional model of the ATLAS planar pixel sensor for the insertable b layer and the super LHC upgrade have been studied. The parameters influencing the breakdown behavior were studied using a finite element method to solve the drift diffusion equations coupled to Poisson's equation. Using these models, the number of guard rings, dead edge width and sensor's thickness were modified with respect to the ATLAS actual pixel sensor to investigate their influence on the sensor's depletion at the edge and on its internal electrical field distribution. The goal of the simulation is to establish a model to discriminate between different designs and to select the most optimized to fit the needs in radiation hardness and low material budget of ATLAS inner detector during super LHC operation. A three defects level model has been implemented in the simulations to study the behavior of such sensors under different level of irradiation. Using the results of our simulations, we propose guidelines for the design of future pixel sensor structures and propose test structures to be inserted in a wafer production to verify and calibrate our simulation model.
author_names: A Lounis

Dominique Martinot

Giovanni Marchiori

Mathieu Benoit

Nicoleta Dinu

Giovanni Calderini
title: TCAD Simulations of ATLAS Pixel Guard Ring and Edge Structure for SLHC Upgrade
year: 2010

abstract: Two dimensional and three dimensional finite element TCAD simulations have been used to investigate the electrical and charge collection properties of fine pitch 3D sensors. The electrical characteristics were compared to experimental results of non irradiated devices, showing a very good agreement, and also proving the effectiveness of the slim edge termination. The charge collection properties of 3D sensors after irradiation up to the maximum fluence expected at HL LHC have been estimated, confirming the very high radiation tolerance of fine pitch devices. SIMULATION OF 3D PIXEL SENSORS CELLS Deliverable: D7.1
author_names: V Radulovic
title: AIDA 2020 Advanced European Infrastructures for Detectors at Accelerators Deliverable Report Simulation of 3 D pixel sensors cells
year: 2016

abstract: Abstract Using finite element simulations with Sentaurus TCAD (Technology Computer Aided Design) software, a progress from simple and classic termination for a Schottky diode to new topology termination has been studied in this paper. A polyimide trench under field plate termination has been used. The efficiency increases from 67% for a simple field plate with optimum parameters up to 97% The maximum electric field in the termination dielectric has been evaluated also. A wide study of the termination geometry has been made in order to extract the optimum parameters in two directions. The first one is to obtain a high efficiency regarding the breakdown voltage, and the second one is to have the minimum electric field peak at the termination edge.
author_names: Houssam Arbess

Karine Isoird

Moustafa Zerarka

Henri Schneider

Marie Laure Locatelli

Dominique Planson
title: High termination efficiency using polyimide trench for high voltage diamond Schottky diode
year: 2015

abstract: An element edge method is developed for the evaluation of stiffness matrix for the 8 node brick element. Handling of large data leads to take more computational time in finite element analysis. The.
author_names: Shyjo Johnson

T Jeyapoovan
title: Evaluation of stiffness matrix in finite element analysis using element edge method for the 8 node brick element
year: 2019

abstract: CMOS scaling became popular among researchers and the semiconductor industry since it provides many advantages like faster speed, higher performance, and increased integration density on a chip. Despite the above advantages, short channel effects are a major concern for planar devices at lower technology nodes which led to the development of multiple gate FETs (MugFET) such as Nanosheet FETs (NSFET) Nanowire FET (NWFET) and FinFET as a replacement for planar MOSFETs. Among all these MugFETs, for sub 7nm technology node, NSFETs are a potential replacement of FinFET and NWFETs due to their high drive current and speed. However, the small channel area and doping profile make these MugFETs more susceptible to Process induced variation. In this thesis, some of these issues are discussed and solutions are proposed. The work presented in this thesis is done using Synopsys Sentaurus TCAD and all the characterization is done using Cascade manual prober along with Keysight B1500 parameter analyzer. In the initial part of the thesis, CMOS FETs are designed and simulated using Sentaurus TCAD to match Semiconductor Laboratory (SCL) CMOS 0.18mm device's physical design and electrical characteristics. Id Vgs of n and p type FETs are measured in linear as well as in the saturation region and finally calibrated using the Sentaurus TCAD model. SOI device's faster speed, resistance to latch up, and immunity against radiation make it preferable over conventional planar devices. PD SOI and FD SOI FETs are also designed to a specific 0.18um CMOS target using a calibrated TCAD model for radiation analysis. MugFETs with small channel area are subject to Line edge roughness (LER) due to process induced variation. LER can result in a high mismatch in FET's electrical characteristics. In this thesis, a 3 D LER model has been taken for the accurate analysis of mismatch in NS and NW FETs electrical characteristics. The mismatch performance of NSFET is investigated and reported for different NS widths. Also, SCE performance parameters, like DIBL (mV) and SS (mV/dec) sensitivity to LER are investigated in this chapter. Moreover, the Junctionless mode devices (JL) are preferred over Inversion mode (IM) devices for nanoscale FETs design due to their simple fabrication process, high drive current, and feasibility of doing short channel length design. However, JL FETs are more susceptible to process induced variation. This thesis also includes a study of matching the performance of inversion (INV) and junctionless (JL) NS/NW FETs devices for 3 D LER. Semiconductor devices are also being widely used in space for various applications, also affected by the presence of Cosmic rays consist of different particles such as heavy ions, neutrons, protons, electrons, alpha particles, and gamma rays. Among these cosmic ray particles, heavy ions cause a change in the state of memory element or temporary circuit failure due to instantaneous transient current spike in devices. In the next part of the thesis, heavy ion induced single event transient (SET) in bulk and SOI NSFET are discussed. Vertically stacked nanosheets are designed and simulated using the inbuilt heavy ion Sentaurus TCAD model. SET current in bulk and SOI NSFETs for different device dimensions are investigated and discussed in this thesis. Also, the effect of the different angles of ion incidence on SET performance is analyzed. SOI NSFETs show a distinct advantage over bulk devices for heavy ion SET. Further, different 3 D SOI MugFETs, such as FinFET, NSFET, and NWFET are simulated for SET due to heavy ion irradiation and compared. Finally, an empirical model is also presented in this thesis to predict the SET current with physical design parameters of MugFETs, and as well as the heavy ion model parameters. Physical design as well as heavy ion parameters, such as nanosheet fin width/ thickness, the diameter of a nanowire, linear energy transfer (LET) angle of incidence, and channel doping are incorporated to accurately predict SET due to heavy ion irradiation on these MugFETs.
title: TCAD Based Modelling of Line Edge Roughness and Radiation Effects in Advanced CMOS Devices
year: 2021

abstract: This paper presents a technique to evaluate the fracture parameters by combining the edge based smoothed finite element method (ESFEM) and the scaled boundary finite element method (SBFEM) A semi analytical solution is sought in the region close to the vicinity of the crack tip using the SBFEM, whilst, the ESFEM is used for the rest of the domain. As both methods satisfy the partition of unity and the compatibility condition, the stiffness matrices obtained from both methods can be assembled as in the conventional finite element method. The stress intensity factors (SIFs) are computed directly from their definition. Numerical examples of linear elastic bodies with cracks are solved without requiring additional post processing techniques. The SIFs computed using the proposed technique are in a good agreement with the reference solutions. A crack propagation study is also carried out with minimal local remeshing to show the robustness of the proposed technique. The maximum circumferential stress criterion is used to predict the direction of propagation.
author_names: Mahesh Surendran

A L N Pramod

Sundararajan Natarajan
title: Evaluation of Fracture Parameters by Coupling the Edge Based Smoothed Finite Element Method and the Scaled Boundary Finite Element Method
year: 2019

abstract: The logical element of matching on the STG DICE cell for a content addressable memory was simulated. The element contains two identical groups of transistors. The TCAD simulation of the 65 nm CMOS element showed the resistance to impacts of single nuclear particles up to 60 MeVxcm2/mg comparing to elements on 6 transistors memory cells. The charge collection from the track of single nuclear particles by only transistors of just one of the two groups doesn't lead to the failure state of the cell. In combinational logic of the element of matching can be short term noise pulses can be registered in the range of the linear energy transfer 20 60 MeVxcm2/mg on the tracks of single nuclear particles.
author_names: Yu V Katunin

Vladimir Ya Stenin
title: TCAD simulation of single event transients in the 65 nm CMOS element of matching for a content addressable memory
venue: 2017 25th Telecommunication Forum (TELFOR)
year: 2017

abstract: Soil tillage is an energy intensive operation and design improvements that reduce forces have been pursued for many different tools. Due to the high cost of prototyping and testing, computer modelling has been adopted to design tillage equipment. In order to model soil tool interaction two methods namely; finite element method (FEM) and discrete element method (DEM) have been used. Fielke (1994 and 1996) found that for shallow working low rake angle tools the cutting edge geometry of a tillage tool has a major effect on tillage forces and soil movement. FEM modelling of the tests was also carried out in Fielke (1999) In this paper the experimental work of Fielke (1994) was simulated using DEM techniques and the results were compared to both the measured data and FEM predicted results. The results of the study showed that better vertical force prediction was obtained using DEM whereas forward soil movements below the tillage depth were simulated more accurately using FEM. This can be attributed to the larger size of particles used in DEM simulation than needed to pass around the cutting edge. It was also shown that DEM can be used to accurately predict soil failure planes.
author_names: Mustafa Ucgul

Chris Saunders

John M Fielke
title: Comparison of the discrete element and finite element methods to model the interaction of soil and tool cutting edge
year: 2018