Advanced SPICE Model for GaN HEMTs (ASM-HEMT): A New Industry-Standard Compact Model for GaN-based Power and RF Circuit Design

Description

This book discusses in detail the Advanced SPICE Model for GaN HEMTs (ASM-HEMT), a new industry standard model for GaN-based power and RF circuit design. The author describes this new, standard model in detail, covering the different components of the ASM GaN model from fundamental derivations to the implementation in circuit simulation tools. The book also includes a detailed description of parameter extraction steps and model quality tests, which are critically important for effective use of this standard model in circuit simulation and product design. Coverage includes both radio-frequency (RF), and power electronics applications of this model. Practical issues related to measurement data and parameter extraction flow are also discussed, enabling readers easily to adopt this new model for design flow and simulation tools. Describes in detail a new industry standard for GaN-based power and RF circuit design;Includes discussion of practical problems and their solutions in GaN device modeling;Covers both radio-frequency (RF) and power electronics application of GaN technology;Describes modeling of both GaN RF and power devices. Preface Acknowledgments Contents Acronyms 1 Gallium Nitride Semiconductor Devices 1.1 Introduction 1.2 Application-Level View of Transistor 1.2.1 Radio-Frequency Power Amplifier Application 1.2.2 Power Electronics Switching Application 1.3 GaN Material Properties 1.3.1 Band-Gap and Breakdown Electric Field 1.3.2 Electron Mobility 1.3.3 Saturation Velocity 1.4 Brief History and Key Advances in GaN Transistors 1.5 Conclusion 2 Compact Modeling 2.1 Introduction to Compact Models 2.2 Types of Compact Models 2.2.1 Measurement-Based Compact Models 2.2.2 Empirical Compact Models 2.2.3 TCAD Models 2.2.4 Neural Network Based Compact Models 2.2.5 Physics-Based Compact Models 2.3 Comparison Among Different Compact Models 2.4 GaN Compact Models 2.5 Compact Model Coalition and Industry Standard GaN Compact Models 3 Introduction to ASM-HEMT Compact Model 3.1 User-Level View of ASM-HEMT Compact Model 3.1.1 Device Geometry Parameters 3.1.2 Model Configuration Switches Model Configuration Switches for Device Architecture Model Configuration Switches for Physical Effects 3.1.3 Device Physics Parameters 3.1.4 Smoothing Parameters 3.2 Components of ASM-HEMT Compact Model 3.3 ASM-HEMT Model Features 4 Core Formulations in ASM-HEMT Model 4.1 Introduction 4.2 Two-Dimensional Electron Gas Model 4.3 Surface-Potential Model 4.4 Terminal Charge Model 4.5 Core Drain Current Model 4.5.1 Mechanisms of Carrier Transport 5 Non-ideal Effects in Device Current and Their Modeling 5.1 Introduction 5.2 Pinch-Off Effect 5.3 Velocity Saturation Effect 5.4 Non-ideal Sub-threshold Slope 5.5 Mobility Dependence of Vertical Field 5.6 Channel-Length Modulation Effect 5.7 Drain-Induced Barrier Lowering Effect 5.8 Non-linear Access Region Resistance Model 6 Trapping Models 6.1 Introduction 6.2 Model with Symmetric Time-Constants 6.3 Model with Asymmetric Time-Constants 6.4 Trapping Model Based on Recombination Generation 6.5 Measurement Results 6.6 Circuit Implementation of a Trap Center 6.6.1 Rates of Charge Capture and Emission at a TrapCenter 6.6.2 Control Potential of a Trap Center 6.6.3 Current Injection into a Trap-Center Region 6.6.4 Circuit Model of a Trap Center 6.6.5 Steady-State Response 6.6.6 Circuit Model for an Electron-Trapping Center 6.7 Discussion 7 Non-Ideal Effects in GaN Capacitances and Their Modeling 7.1 Introduction 7.2 Impact of Fringe Capacitances 7.3 Impact of Field-Plates on Device Capacitance 7.3.1 Gate–Source Capacitance 7.3.2 Gate–Drain Capacitance 7.3.3 Drain–Source Capacitance 7.4 Impact of High Field Region on Capacitance 7.5 Impact of Charge Trapping on Capacitance 7.6 Substrate Bias Effects and Substrate Capacitance 8 Gate Current Model 8.1 Diode-Based Formulation 8.2 Model Based on Frenkel–Poole Mechanism 8.3 Gate Current with Consistency with Drain Current 8.3.1 Thermionic Emission Model 8.3.2 Poole–Frenkel Model 8.3.3 Fowler–Nordheim Model 9 Effect of Ambient Temperature on GaN Device 9.1 Introduction 9.2 Temperature Dependence of Parameters Affecting DrainCurrent 9.2.1 Cut-Off Voltage 9.2.2 Mobility 9.2.3 Saturation Velocity 9.2.4 Access Region Charge Density 9.2.5 Contact Resistance 9.3 Temperature Dependence of Gate Current Parameters 9.4 Self-Heating Effect and Modeling for Multiple Ambient Temperatures 10 Noise Models 10.1 Flicker Noise 10.2 Thermal Noise 11 Parameter Extraction in ASM-HEMT Model 11.1 GaN RF Device Extraction Flow 11.1.1 DC Parameter Extraction 11.1.2 S-Parameter Model 11.1.3 Non-Linear Large Signal Model 11.2 GaN Power Device Extraction Flow 11.2.1 I-V Parameter Extraction 11.2.2 Capacitance Modeling 11.2.3 Modeling the Package Parasitics 11.3 Model Quality Tests 11.3.1 Gummel Symmetry Test Results 11.3.2 Harmonic Balance Simulation Results 11.3.3 AC Symmetry Test Results 11.3.4 Reciprocity Test Results 12 Advance Simulations with ASM-HEMT Model 12.1 Manufacturing Variation and RF Device Stability Analysis 12.1.1 Custom Python Script 12.1.2 Non-Linear Stability Analysis in the Presence of Manufacturing Variations 12.1.3 Nominal Device Non-Linear Stability Analysis 12.2 GaN Power Device Circuit Simulations Using ASM-HEMT 12.3 Design Technology Co-optimization Using ASM-HEMT 12.3.1 Barrier Thickness Dependence of AM/PM 12.3.2 Field-Plate Dependence of AM/PM 13 Resources for ASM-HEMT Model Users 13.1 GITHUB Repository References Index