Sentaurus DeviceVersion Y-2006.06, June 2006

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Sentaurus Device, Y-2006.06

SENTAURUS DEVICE CONTENTS

Sentaurus DeviceAbout this manual ............................................................................................................................xxiii

Audience ..........................................................................................................................................................xxiiiRelated publications.........................................................................................................................................xxiiiTypographic conventions ................................................................................................................................ xxivCustomer support............................................................................................................................................ xxivAcknowledgments ............................................................................................................................................ xxv

Part I Getting Started................................................................................................ 1Chapter 1 Overview...............................................................................................................................3

About Sentaurus Device ......................................................................................................................................3Creating and meshing device structures ........................................................................................................5Tool flow .........................................................................................................................................................6

Starting Sentaurus Device ...................................................................................................................................6From command line........................................................................................................................................6From Sentaurus Workbench ..........................................................................................................................7

Simulation examples ............................................................................................................................................8Example: Simple MOSFET IdVg simulation.......................................................................................................8

Input command file .........................................................................................................................................8File section .....................................................................................................................................................9Electrode section..........................................................................................................................................10Physics section.............................................................................................................................................11Plot section...................................................................................................................................................12Math section .................................................................................................................................................12Solve section ................................................................................................................................................13Simulated IdVg characteristic.....................................................................................................................14Analysis of 2D output data ...........................................................................................................................15

Example: Advanced hydrodynamic IdVd simulation ........................................................................................17Input command file .......................................................................................................................................17File section ...................................................................................................................................................19

Main options..........................................................................................................................................20Parameter file ...............................................................................................................................................20

Listing of mos.par..................................................................................................................................20Report in protocol file n3_des.log..........................................................................................................20

Electrode section..........................................................................................................................................21Main options..........................................................................................................................................21

Physics section.............................................................................................................................................21Main options..........................................................................................................................................22

Interface physics ..........................................................................................................................................23Main options..........................................................................................................................................23

Plot section...................................................................................................................................................23CurrentPlot section.......................................................................................................................................23

Main options..........................................................................................................................................24Math section .................................................................................................................................................24

Example ................................................................................................................................................24Solve section ................................................................................................................................................25Two-dimensional output data .......................................................................................................................28

Example: Mixed-mode CMOS inverter simulation .............................................................................................29Input command file .......................................................................................................................................29Device section ..............................................................................................................................................31System section .............................................................................................................................................32File section ...................................................................................................................................................33

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Plot section...................................................................................................................................................33Math section .................................................................................................................................................33Solve section ................................................................................................................................................34Results of inverter transient simulation ........................................................................................................35

Example: Small-signal AC extraction .................................................................................................................35Input command file .......................................................................................................................................36Device section ..............................................................................................................................................37File section ...................................................................................................................................................38System section .............................................................................................................................................38Solve section ................................................................................................................................................39Results of AC simulation ..............................................................................................................................40

Chapter 2 Basic Sentaurus Device ....................................................................................................41Overview ............................................................................................................................................................41

Specifying the device ...................................................................................................................................41Defining the output .......................................................................................................................................41Specifying the simulation..............................................................................................................................42Inserting files ................................................................................................................................................42

File section .........................................................................................................................................................43Electrode section................................................................................................................................................43

Workfunction and material specifications for contacts .................................................................................44Thermode section ..............................................................................................................................................46Physics section ..................................................................................................................................................47

Physics section example ..............................................................................................................................47Region-specific and material-specific physics..............................................................................................48Physics at interfaces ....................................................................................................................................49

Interface model syntax ..........................................................................................................................49Interface model parameters ..................................................................................................................49

Physics at electrodes ...................................................................................................................................50Plot section.........................................................................................................................................................50

Interface plots...............................................................................................................................................51CurrentPlot section.............................................................................................................................................52

Example: Node numbers..............................................................................................................................53Example: Mixed mode..................................................................................................................................54Example: Advanced options.........................................................................................................................54Example: Physical parameter values ...........................................................................................................55

TrappedCarDistrPlot section ..............................................................................................................................55NonLocalPlot section .........................................................................................................................................55Solve section......................................................................................................................................................55

Coupled command .......................................................................................................................................56Plugin command...........................................................................................................................................57Quasistationary command............................................................................................................................58

Ramping boundary conditions...............................................................................................................59Ramping physical parameter values .....................................................................................................60Saving and plotting data during Quasistationary solve sequence.........................................................62

Transient command......................................................................................................................................62Large-signal cyclic analysis..........................................................................................................................63

Description of method ...........................................................................................................................64Using cyclic analysis .............................................................................................................................66

Plot, Save, and Load commands .................................................................................................................66Example: Solve section of input file with Plot, Save, and Load operations...........................................67Example: Solve section of input file with multiple Save and Load operations.......................................68

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System command.........................................................................................................................................69NewCurrentPrefix statement ........................................................................................................................69CurrentPlot section.......................................................................................................................................70

Example: CurrentPlot statements .........................................................................................................71Set command ...............................................................................................................................................72

Math section.......................................................................................................................................................72Device-specific Math keywords ....................................................................................................................72

Physics-related Math keywords ............................................................................................................73Derivatives ............................................................................................................................................73Discretization methods..........................................................................................................................74

Math parameters for nonlinear iterations convergence control ....................................................................75Math parameters for transient analysis ........................................................................................................76Solver-oriented Math keywords....................................................................................................................77Break criteria ................................................................................................................................................78Parallelization ...............................................................................................................................................80Nonlocal line meshes ...................................................................................................................................81

Specifying nonlocal line meshes ...........................................................................................................81Visualizing nonlocal line meshes ..........................................................................................................81Visualizing data defined on nonlocal line meshes.................................................................................82Constructing nonlocal line mesh ...........................................................................................................83Special handling of 1D Schrdinger equation .......................................................................................84Special handling of nonlocal tunneling model .......................................................................................85Performance suggestions .....................................................................................................................85

Monitoring convergence behavior ................................................................................................................86CNormPrint ...........................................................................................................................................86NewtonPlot............................................................................................................................................86

Incomplete Newton algorithm.......................................................................................................................87Specifying model parameters.............................................................................................................................88

Specifying region and material parameters..................................................................................................88Generating a copy of parameter file .............................................................................................................88Changing parameter values in parameter file ..............................................................................................89Library of materials.......................................................................................................................................89Parameters of compound materials .............................................................................................................91Undefined physical models ..........................................................................................................................92Default parameters.......................................................................................................................................93

Hierarchy of models and parameters .................................................................................................................93Model hierarchy............................................................................................................................................94Parameter hierarchy.....................................................................................................................................94

Material and doping specification.......................................................................................................................95User-defined materials .................................................................................................................................96User-defined species....................................................................................................................................97

Tcl command file ................................................................................................................................................99Overview ......................................................................................................................................................99sdevice command ......................................................................................................................................101sdevice_init command................................................................................................................................101sdevice_solve command ............................................................................................................................101sdevice_finish command ............................................................................................................................102Flowchart....................................................................................................................................................102sdevice_parameters command ..................................................................................................................102Extraction ...................................................................................................................................................103Output redirection.......................................................................................................................................104Known restrictions ......................................................................................................................................104

Saving snapshots.............................................................................................................................................104

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Chapter 3 Mixed-mode Sentaurus Device.......................................................................................107Overview ..........................................................................................................................................................107

Compact models ........................................................................................................................................107Hierarchical description of compact models...............................................................................................108Example: Compact models ........................................................................................................................110

SPICE circuit files.............................................................................................................................................111Device section..................................................................................................................................................112System section.................................................................................................................................................113

Physical devices.........................................................................................................................................114Circuit devices ............................................................................................................................................115Electrical and thermal netlist ......................................................................................................................115Set, Unset, Initialize, and Hint ....................................................................................................................117System Plot ................................................................................................................................................118AC System Plot ..........................................................................................................................................119

File section .......................................................................................................................................................120SPICE circuit models .......................................................................................................................................121User-defined circuit models..............................................................................................................................121Solve section....................................................................................................................................................122

Coupled command .....................................................................................................................................122Circuit and contact equation-variable keywords..................................................................................122Selecting individual devices ................................................................................................................123

Quasistationary command..........................................................................................................................124ACCoupled: Small-signal AC analysis .......................................................................................................125

Example: AC analysis of simple device ..............................................................................................126Optical AC analysis ....................................................................................................................................127Harmonic balance ......................................................................................................................................128

Performing harmonic balance analysis ...............................................................................................128Harmonic balance analysis output ......................................................................................................129Application notes.................................................................................................................................130

Continuation: Alternative ramping method .................................................................................................130Example: Solve entry for continuation.................................................................................................131

Set and Unset section ................................................................................................................................132Accessing SPICE vector parameters .........................................................................................................132

Math section.....................................................................................................................................................133Using mixed-mode simulation ..........................................................................................................................133

From single-device file to multidevice file...................................................................................................133File-naming convention: Mixed-mode extension ........................................................................................135

Part II Physics in Sentaurus Device..................................................................... 137Chapter 4 Introduction to physics in Sentaurus Device................................................................139

Transport equations .........................................................................................................................................139Poisson equation and continuity equations ................................................................................................140Drift-diffusion model ...................................................................................................................................140Thermodynamic transport model................................................................................................................141

Thermodynamic model........................................................................................................................141Using the thermodynamic model.........................................................................................................142

Uniform self-heating ...................................................................................................................................143Using uniform self-heating ..................................................................................................................144

Hydrodynamic transport model ..................................................................................................................144Using the hydrodynamic model...........................................................................................................145Hydrodynamic model ..........................................................................................................................145

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Hydrodynamic model parameters .......................................................................................................149Conductivity of metals ................................................................................................................................149Conductive insulators .................................................................................................................................152

Quasi-Fermi potential.......................................................................................................................................155Fermi statistics .................................................................................................................................................156

Using Fermi statistics .................................................................................................................................157Boundary conditions.........................................................................................................................................157

Electrical boundary conditions....................................................................................................................157Ohmic contacts ...................................................................................................................................157Gate contacts ......................................................................................................................................158Schottky contacts ................................................................................................................................159Barrier lowering at Schottky contacts..................................................................................................160Resistive contacts ...............................................................................................................................160Floating metal gates............................................................................................................................162Floating semiconductor gates .............................................................................................................163Boundaries without contacts ...............................................................................................................164

Thermal boundary conditions for thermodynamic model ...........................................................................164Thermal boundary conditions for hydrodynamic model..............................................................................165Total thermal resistance .............................................................................................................................165

Estimating thermal resistance .............................................................................................................166Periodic boundary conditions .....................................................................................................................166

Starting solution or initial guess......................................................................................................................168Electrostatic potential and quasi-Fermi potentials: Wells ...........................................................................168Regionwise specification of initial quasi-Fermi potentials ..........................................................................169Thermodynamic and hydrodynamic simulations ........................................................................................169Save file overrides the initial guess ............................................................................................................169

Chapter 5 Semiconductor band structure ......................................................................................171Intrinsic density ................................................................................................................................................171Band gap and electron affinity..........................................................................................................................171

Selecting the band gap model....................................................................................................................172Bandgap and electron-affinity models ........................................................................................................172

Bandgap narrowing for BennettWilson model...................................................................................173Bandgap narrowing for Slotboom model.............................................................................................173Bandgap narrowing for del Alamo model ............................................................................................174Table specification of bandgap narrowing...........................................................................................174Bandgap narrowing with Fermi statistics.............................................................................................175

Bandgap parameters..................................................................................................................................175Effective masses and effective density-of-states .............................................................................................176

Electron effective mass and DOS ..............................................................................................................177Formula 1 ............................................................................................................................................177Formula 2 ............................................................................................................................................177

Electron effective mass and conduction band DOS parameters................................................................178Hole effective mass and DOS ....................................................................................................................178

Formula 1 ............................................................................................................................................178Formula 2 ............................................................................................................................................179

Hole effective mass and valence band DOS parameters...........................................................................179

Chapter 6 Incomplete ionization ......................................................................................................181Using incomplete ionization .............................................................................................................................181Incomplete ionization model.............................................................................................................................182Physical model parameters..............................................................................................................................183

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Chapter 7 Quantization models .......................................................................................................185Overview ..........................................................................................................................................................185van Dort quantization model ............................................................................................................................186

van Dort model ...........................................................................................................................................186Using the van Dort model...........................................................................................................................186

1D Schrdinger solver......................................................................................................................................187Nonlocal mesh for 1D Schrdinger ............................................................................................................187Using 1D Schrdinger ................................................................................................................................1881D Schrdinger parameters .......................................................................................................................189

Explicit ladder specification .................................................................................................................189Automatic extraction of ladder parameters .........................................................................................189

Visualizing Schrdinger solutions...............................................................................................................1911D Schrdinger model................................................................................................................................1911D Schrdinger application notes ..............................................................................................................192

Density gradient quantization model ................................................................................................................192Density gradient model...............................................................................................................................192Using the density gradient model ...............................................................................................................194Density gradient application notes .............................................................................................................195

Modified local-density approximation ...............................................................................................................196MLDA model...............................................................................................................................................196Using MLDA ...............................................................................................................................................196MLDA application notes .............................................................................................................................197

Chapter 8 Mobility models................................................................................................................199How mobility models combine..........................................................................................................................199Mobility due to phonon scattering ....................................................................................................................200Doping-dependent mobility degradation ..........................................................................................................200

Using doping-dependent mobility ...............................................................................................................200Masetti model .............................................................................................................................................201Arora model................................................................................................................................................202University of Bologna bulk mobility model..................................................................................................202

Mobility degradation at interfaces ....................................................................................................................204Using mobility degradation at interfaces ....................................................................................................204Enhanced Lombardi model ........................................................................................................................205University of Bologna surface mobility model.............................................................................................207Computing transverse field.........................................................................................................................209

Normal to interface..............................................................................................................................209Normal to current flow .........................................................................................................................210

Carriercarrier scattering .................................................................................................................................210Using carriercarrier scattering ..................................................................................................................211ConwellWeisskopf model .........................................................................................................................211BrooksHerring model................................................................................................................................211Physical model parameters ........................................................................................................................212

Philips unified mobility model ...........................................................................................................................212Using Philips model....................................................................................................................................212Using an alternative Philips model .............................................................................................................213Philips model description............................................................................................................................213Screening parameter..................................................................................................................................215Philips model parameters...........................................................................................................................215

High-field saturation .........................................................................................................................................217Using high-field saturation..........................................................................................................................217Extended Canali model ..............................................................................................................................217Transferred electron model ........................................................................................................................219

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Basic model................................................................................................................................................219MeinerzhagenEngl model.........................................................................................................................220Lucent model..............................................................................................................................................220Velocity saturation models .........................................................................................................................221

Selecting velocity saturation models ...................................................................................................221Driving force models...................................................................................................................................221

Monte Carlocomputed mobility for strained silicon.........................................................................................222Monte Carlocomputed mobility for strained SiGe in npn-SiGe HBTs.............................................................223Incomplete ionizationdependent mobility models...........................................................................................223

Chapter 9 Generationrecombination .............................................................................................225ShockleyReadHall (SRH) recombination .....................................................................................................225

Using SRH recombination ..........................................................................................................................226SRH doping dependence ...........................................................................................................................226Lifetime profiles from files...........................................................................................................................227SRH temperature dependence...................................................................................................................227SRH doping- and temperature-dependent parameters ..............................................................................228SRH field enhancement .............................................................................................................................228

Using field enhancement.....................................................................................................................229Schenk trap-assisted tunneling (TAT) model ......................................................................................229Schenk TAT density correction ...........................................................................................................231Hurkx TAT model ................................................................................................................................231Field-enhancement parameters ..........................................................................................................232

Trap-assisted Auger recombination ...........................................................................................................232Surface SRH recombination.............................................................................................................................233Coupled defect level (CDL) recombination ......................................................................................................234

Using CDL ..................................................................................................................................................234CDL model .................................................................................................................................................235

Radiative recombination...................................................................................................................................236Using radiative recombination ....................................................................................................................236Radiative model..........................................................................................................................................236

Auger recombination ........................................................................................................................................237Avalanche generation ......................................................................................................................................238

Using avalanche generation.......................................................................................................................238van Overstraeten de Man model .............................................................................................................239OkutoCrowell model .................................................................................................................................240Lackner model............................................................................................................................................240University of Bologna impact ionization model...........................................................................................241New University of Bologna impact ionization model...................................................................................242Driving force ...............................................................................................................................................244Avalanche generation with hydrodynamic transport...................................................................................245

Approximate breakdown analysis: Poisson equation approach.......................................................................246Using breakdown analysis..........................................................................................................................247

Band-to-band tunneling models .......................................................................................................................248Schenk model.............................................................................................................................................248

Using Schenk band-to-band tunneling ................................................................................................249Simple band-to-band model .......................................................................................................................249

Using simple band-to-band model ......................................................................................................249Hurkx band-to-band model.........................................................................................................................250

Using Hurkx band-to-band model .......................................................................................................250Tunneling near interfaces and equilibrium regions.....................................................................................251

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Chapter 10 Traps and fixed charges ...............................................................................................253Basic syntax for traps.......................................................................................................................................253Trap types ........................................................................................................................................................254Energetic and spatial distribution of traps ........................................................................................................254Trap models and parameters ...........................................................................................................................255

Trap occupation dynamics .........................................................................................................................255Local trap capture and emission ................................................................................................................256

J-model cross sections........................................................................................................................257Hurkx model for cross sections ...........................................................................................................258PooleFrenkel model for cross sections .............................................................................................258

Tunneling and traps....................................................................................................................................258Trap numeric parameters.................................................................................................................................259Visualizing traps ...............................................................................................................................................260Explicit trap occupation ....................................................................................................................................261Trap examples .................................................................................................................................................262Insulator fixed charges .....................................................................................................................................262

Chapter 11 Degradation model ........................................................................................................265Overview ..........................................................................................................................................................265Trap formation kinetics.....................................................................................................................................265

Power law and kinetic equation..................................................................................................................265Si-H densitydependent activation energy.................................................................................................266Diffusion of hydrogen in oxide ....................................................................................................................266

Syntax and parameterized equations...............................................................................................................267Device lifetime and simulation..........................................................................................................................270

Chapter 12 Optical generation .........................................................................................................273Generating photon beams................................................................................................................................273Absorption models ...........................................................................................................................................276

Default absorption model from parameter file ............................................................................................277Table-based optical properties of materials in parameter file.....................................................................278Absorption coefficient model ......................................................................................................................279

Optical generation by raytracing ......................................................................................................................280Physical model ...........................................................................................................................................281Refractive index model...............................................................................................................................282Absorption model .......................................................................................................................................283Using absorption model..............................................................................................................................283Window of ray.............................................................................................................................................284Two-dimensional device and window description ......................................................................................286Three-dimensional device and window description....................................................................................287Spatial distribution of intensity....................................................................................................................288Polarization.................................................................................................................................................292Boundary condition for raytracing...............................................................................................................293

Constant reflectivity boundary condition .............................................................................................293Thin-layer-stack boundary condition ...................................................................................................294

Additional options for raytracing .................................................................................................................296Dual-grid setup for raytracing .....................................................................................................................296

Optical generation by transfer matrix approach ...............................................................................................298Physical model ...........................................................................................................................................298Using optical generation.............................................................................................................................301

Optical generation from FDTD simulation (EMW)............................................................................................303Files of EMW generation ............................................................................................................................303

Creating the tensor grid and EMW input command file.......................................................................304

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User-defined input or tensor grid.........................................................................................................304Log of EMW run ..................................................................................................................................305

Syntax of EMW generation: Input file of EMW ...........................................................................................305Boundary.............................................................................................................................................306Excitation.............................................................................................................................................307Excitation example 1 ...........................................................................................................................309Material/AutoMatGen ..........................................................................................................................309

EMW generation: Tensor grid, syntax, and algorithm ................................................................................313GridBoundX, GridBoundY, and GridBoundZ.......................................................................................313SmoothingFactor.................................................................................................................................315

Multithreading for EMW generation: Syntax...............................................................................................315Optical generation by beam propagation method ............................................................................................316

Physical model ...........................................................................................................................................316Boundary conditions............................................................................................................................317

Using beam propagation method ...............................................................................................................318General ...............................................................................................................................................318Excitation.............................................................................................................................................318Boundary.............................................................................................................................................321Optics stand-alone option ...................................................................................................................321Ramping input parameters..................................................................................................................322

Loading optical generation from file .................................................................................................................323Wavelength ramping for computing optical generation ....................................................................................323Optical AC analysis ..........................................................................................................................................325

Chapter 13 Radiation models...........................................................................................................327Generation by gamma radiation.......................................................................................................................327

Using gamma radiation model....................................................................................................................327Yield function..............................................................................................................................................327

Alpha particles..................................................................................................................................................328Using alpha particle model .........................................................................................................................328Alpha particle model...................................................................................................................................329

Heavy ions .......................................................................................................................................................330Using heavy ion model ...............................................................................................................................330Heavy ion model.........................................................................................................................................330Examples: Heavy ions................................................................................................................................332

Example 1 ...........................................................................................................................................332Example 2 ...........................................................................................................................................333

Improved alpha particle/heavy ion generation rate integration ........................................................................333

Chapter 14 Noise and fluctuation analysis .....................................................................................335Performing noise and fluctuation analysis........................................................................................................335Noise sources ..................................................................................................................................................337

Diffusion noise............................................................................................................................................337Equivalent monopolar generationrecombination noise ............................................................................337Bulk flicker noise ........................................................................................................................................338Random dopant fluctuations.......................................................................................................................338Noise from SPICE circuit elements ............................................................................................................339

Impedance field method...................................................................................................................................339Noise output data .............................................................................................................................................340

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Chapter 15 Tunneling........................................................................................................................343Tunneling model overview ...............................................................................................................................343FowlerNordheim tunneling .............................................................................................................................344

Using FowlerNordheim.............................................................................................................................344FowlerNordheim model ............................................................................................................................345FowlerNordheim parameters....................................................................................................................345

Direct tunneling ................................................................................................................................................346Using direct tunneling.................................................................................................................................346Direct tunneling model................................................................................................................................347

Image force effect ...............................................................................................................................347Direct tunneling parameters .......................................................................................................................349

Nonlocal tunneling at interfaces and contacts..................................................................................................349Defining nonlocal mesh ..............................................................................................................................350Specifying nonlocal tunneling model ..........................................................................................................350Nonlocal tunneling parameters...................................................................................................................352Visualizing nonlocal tunneling ....................................................................................................................353Physics of nonlocal tunneling model ..........................................................................................................353

WKB tunneling probability ...................................................................................................................353Schrdinger equationbased tunneling probability .............................................................................355Density gradient quantization correction .............................................................................................356Nonlocal tunneling current ..................................................................................................................356Band-to-band contributions to nonlocal tunneling current...................................................................357Carrier heating ....................................................................................................................................357Implementation consideration .............................................................................................................359

Chapter 16 Hot-carrier injection models .........................................................................................361Overview ..........................................................................................................................................................361Classical lucky electron injection......................................................................................................................363Fiegna hot-carrier injection...............................................................................................................................364Carrier injection with explicitly evaluated boundary conditions for continuity equations ..................................365

Chapter 17 Heterostructure device simulation...............................................................................367Physics models and differential equations .......................................................................................................367Mole fraction materials .....................................................................................................................................367Mole fraction specification................................................................................................................................369Composition-dependent models ......................................................................................................................371Ternary semiconductor composition ................................................................................................................372

Example 1: Specifying electron effective mass ..........................................................................................373Example 2: Specifying dielectric permittivity ..............................................................................................374Example 3: Specifying band gap................................................................................................................374

Quaternary semiconductor composition...........................................................................................................375Default model parameters for compound semiconductors...............................................................................376Abrupt and graded heterojunctions ..................................................................................................................377Thermionic emission current ............................................................................................................................378

Using thermionic emission current .............................................................................................................378Thermionic emission model........................................................................................................................379

Chapter 18 Energy-dependent parameters.....................................................................................381Overview ..........................................................................................................................................................381Energy-dependent energy relaxation time .......................................................................................................381

Spline interpolation.....................................................................................................................................383Energy-dependent mobility ..............................................................................................................................384

Spline interpolation.....................................................................................................................................385

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Energy-dependent Peltier coefficient ...............................................................................................................386Spline interpolation.....................................................................................................................................387

Chapter 19 Anisotropic properties ..................................................................................................389Anisotropic mobility ..........................................................................................................................................390

Crystal reference system............................................................................................................................390Anisotropy factor ........................................................................................................................................390Current densities ........................................................................................................................................390Driving forces .............................................................................................................................................392Total anisotropic mobility............................................................................................................................393Total direction-dependent anisotropic mobility ...........................................................................................393Self-consistent anisotropic mobility ............................................................................................................394Plot section.................................................................................................................................................395

Anisotropic avalanche generation ....................................................................................................................396Anisotropic electrical permittivity ......................................................................................................................397Anisotropic thermal conductivity.......................................................................................................................398

Chapter 20 Ferroelectric materials ..................................................................................................401Using ferroelectrics ..........................................................................................................................................401Ferroelectrics model.........................................................................................................................................402

Chapter 21 Modeling mechanical stress effect ..............................................................................405Overview ..........................................................................................................................................................405Deformation of band structure..........................................................................................................................406

Using deformation potential model.............................................................................................................407Piezoresistive mobility change .........................................................................................................................408

Using piezoresistive model.........................................................................................................................410Strain-induced mobility model ..........................................................................................................................410

Using strain-induced mobility model...........................................................................................................412Intel stress-induced hole mobility model ..........................................................................................................413

Stress dependencies..................................................................................................................................414Generalization of model .............................................................................................................................414Using Intel mobility model ..........................................................................................................................416

Using stress-dependent models.......................................................................................................................417Dependence saturation velocity on stress .......................................................................................................418Stress mobility model for minority carriers .......................................................................................................419Piezoelectric polarization .................................................................................................................................420

Strain model ...............................................................................................................................................421Stress model ..............................................................................................................................................421Poisson equation........................................................................................................................................422Parameter file .............................................................................................................................................422Coordinate systems....................................................................................................................................423

Chapter 22 Galvanic transport model .............................................................................................425Syntax and implementation..............................................................................................................................425Model description .............................................................................................................................................425

Chapter 23 Thermal properties ........................................................................................................427Heat capacity ...................................................................................................................................................427Temperature-dependent lattice heat capacity..................................................................................................427Thermal conductivity ........................................................................................................................................428Temperature-dependent thermal conductivity..................................................................................................428Thermoelectric power (TEP) ............................................................................................................................429

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SENTAURUS DEVICECONTENTS

Part III Physics of Lasers and Light-Emitting Diodes ......................................... 431Chapter 24 Introduction to lasers and LEDs ..................................................................................433

Overview ..........................................................................................................................................................433Command file syntax........................................................................................................................................435

Simulating single-grid edge-emitting laser .................................................................................................435Simulating dual-grid edge-emitting laser ..