Modeling And Electrothermal Simulation Of Sic Power Devices: Using Silvaco© Atlas


Book Description

The primary goal of this book is to provide a sound understanding of wide bandgap Silicon Carbide (SiC) power semiconductor device simulation using Silvaco© ATLAS Technology Computer Aided Design (TCAD) software. Physics-based TCAD modeling of SiC power devices can be extremely challenging due to the wide bandgap of the semiconductor material. The material presented in this book aims to shorten the learning curve required to start successful SiC device simulation by providing a detailed explanation of simulation code and the impact of various modeling and simulation parameters on the simulation results. Non-isothermal simulation to predict heat dissipation and lattice temperature rise in a SiC device structure under switching condition has been explained in detail. Key pointers including runtime error messages, code debugging, implications of using certain models and parameter values, and other factors beneficial to device simulation are provided based on the authors' experience while simulating SiC device structures. This book is useful for students, researchers, and semiconductor professionals working in the area of SiC semiconductor technology. Readers will be provided with the source code of several fully functional simulation programs that illustrate the use of Silvaco© ATLAS to simulate SiC power device structure, as well as supplementary material for download.




Simulation, Modeling and Characterization of SiC Devices


Book Description

With superior material properties, Silicon carbide (SiC) power devices show great potential for high-power density, high temperature switching applications. Among all the power device structures, SiC MOSFET attracts the most attention because of its high gate input impedance, simple gate control and fast switching speed. However, low inversion channel mobility, high near-interface state density close to the conduction band edge, questionable oxide reliability as well as theoretical limit on the device figure-of-merit still remain to be significant challenges to the development of SiC power MOSFETs. In this dissertation, all of the above challenges are addressed from various approaches. First, simulations on the super-junction structure show that the unipolar theoretical limit of SiC can be broken even with the state-of-the-art processing technologies. An easy-to-implement analytical model is developed for calculations of the blocking voltage, specific on-resistance and charge imbalance effects of 4H-SiC super-junction devices. This model is validated by extensive numerical simulations with a large variety of device parameters. Device design and optimization using this model are also presented. Second, a wafer-level Hall mobility measurement technique is developed to measure channel mobility more accurately, more efficiently and more cost-effectively. Device characterization and development are much more convenient by using this technique. With this method, further explorations of interactions between interface traps and channel carriers as well as device degradation mechanisms become possible. Third, reliability of SiO2 on 4H-SiC is characterized with time dependent dielectric breakdown (TDDB) measurements at various temperatures and electric fields. Lifetime prediction to normal operation conditions suggests that the oxide on SiC has a characteristic lifetime of 10 years at 375° C if the oxide electric field is kept below 4.6 MV/cm. The observed excellent reliability data contradict the widespread belief that the oxide on SiC is intrinsically limited by its physical properties. Detailed discussions are provided to re-examine the arguments leading to the misconception.







Vertical GaN and SiC Power Devices


Book Description

This unique new resource provides a comparative introduction to vertical Gallium Nitride (GaN) and Silicon Carbide (SiC) power devices using real commercial device data, computer, and physical models. This book uses commercial examples from recent years and presents the design features of various GaN and SiC power components and devices. Vertical verses lateral power semiconductor devices are explored, including those based on wide bandgap materials. The abstract concepts of solid state physics as they relate to solid state devices are explained with particular emphasis on power solid state devices. Details about the effects of photon recycling are presented, including an explanation of the phenomenon of the family tree of photon-recycling. This book offers in-depth coverage of bulk crystal growth of GaN, including hydride vapor-phase epitaxial (HVPE) growth, high-pressure nitrogen solution growth, sodium-flux growth, ammonothermal growth, and sublimation growth of SiC. The fabrication process, including ion implantation, diffusion, oxidation, metallization, and passivation is explained. The book provides details about metal-semiconductor contact, unipolar power diodes, and metal-insulator-semiconductor (MIS) capacitors. Bipolar power diodes, power switching devices, and edge terminations are also covered in this resource.




Electro-thermal Modeling of SiC Power Electronic Systems


Book Description

As the development of Silicon (Si) semiconductor technology slows down due to its material limitations, more and more attention is being paid to wide bandgap material based semiconductor technology. Silicon Carbide (SiC) has been widely recognized as the material for next generation power electronic devices. However, a great deal of work needs to be done before SiC power devices can be widely applied. This dissertation addresses this need and has conducted research on the modeling of SiC power electronic system. More specifically, a method for system modeling of a SiC power system based on basic physics and device tests is presented here. It includes temperature-dependent single device models specified for system-level modeling, power loss models for power converters, and thermal models for cooling system. The method is verified by experimental results. Furthermore, it is used to study the system impact of SiC power devices in several different applications, which were funded by Small Business Innovation Research (SBIR) and Oak Ridge National Laboratory (ORNL). A conclusion is drawn from these studies that SiC power devices are more suitable for high-power, high-temperature, and high-frequency systems compared to Si ones. Thus, these kinds of systems will be the potential applications of SiC power devices in the near future.




Transient Electro-Thermal Modeling on Power Semiconductor Devices


Book Description

This book presents physics-based electro-thermal models of bipolar power semiconductor devices including their packages, and describes their implementation in MATLAB and Simulink. It is a continuation of our first book Modeling of Bipolar Power Semiconductor Devices. The device electrical models are developed by subdividing the devices into different regions and the operations in each region, along with the interactions at the interfaces, are analyzed using the basic semiconductor physics equations that govern device behavior. The Fourier series solution is used to solve the ambipolar diffusion equation in the lightly doped drift region of the devices. In addition to the external electrical characteristics, internal physical and electrical information, such as junction voltages and carrier distribution in different regions of the device, can be obtained using the models. The instantaneous dissipated power, calculated using the electrical device models, serves as input to the thermal model (RC network with constant and nonconstant thermal resistance and thermal heat capacity, or Fourier thermal model) of the entire module or package, which computes the junction temperature of the device. Once an updated junction temperature is calculated, the temperature-dependent semiconductor material parameters are re-calculated and used with the device electrical model in the next time-step of the simulation. The physics-based electro-thermal models can be used for optimizing device and package design and also for validating extracted parameters of the devices. The thermal model can be used alone for monitoring the junction temperature of a power semiconductor device, and the resulting simulation results used as an indicator of the health and reliability of the semiconductor power device.










Technology Computer Aided Design


Book Description

Responding to recent developments and a growing VLSI circuit manufacturing market, Technology Computer Aided Design: Simulation for VLSI MOSFET examines advanced MOSFET processes and devices through TCAD numerical simulations. The book provides a balanced summary of TCAD and MOSFET basic concepts, equations, physics, and new technologies related to TCAD and MOSFET. A firm grasp of these concepts allows for the design of better models, thus streamlining the design process, saving time and money. This book places emphasis on the importance of modeling and simulations of VLSI MOS transistors and TCAD software. Providing background concepts involved in the TCAD simulation of MOSFET devices, it presents concepts in a simplified manner, frequently using comparisons to everyday-life experiences. The book then explains concepts in depth, with required mathematics and program code. This book also details the classical semiconductor physics for understanding the principle of operations for VLSI MOS transistors, illustrates recent developments in the area of MOSFET and other electronic devices, and analyzes the evolution of the role of modeling and simulation of MOSFET. It also provides exposure to the two most commercially popular TCAD simulation tools Silvaco and Sentaurus. • Emphasizes the need for TCAD simulation to be included within VLSI design flow for nano-scale integrated circuits • Introduces the advantages of TCAD simulations for device and process technology characterization • Presents the fundamental physics and mathematics incorporated in the TCAD tools • Includes popular commercial TCAD simulation tools (Silvaco and Sentaurus) • Provides characterization of performances of VLSI MOSFETs through TCAD tools • Offers familiarization to compact modeling for VLSI circuit simulation R&D cost and time for electronic product development is drastically reduced by taking advantage of TCAD tools, making it indispensable for modern VLSI device technologies. They provide a means to characterize the MOS transistors and improve the VLSI circuit simulation procedure. The comprehensive information and systematic approach to design, characterization, fabrication, and computation of VLSI MOS transistor through TCAD tools presented in this book provides a thorough foundation for the development of models that simplify the design verification process and make it cost effective.




POWER/HVMOS Devices Compact Modeling


Book Description

Semiconductor power electronics plays a dominant role due its increased efficiency and high reliability in various domains including the medium and high electrical drives, automotive and aircraft applications, electrical power conversion, etc. Power/HVMOS Devices Compact Modeling will cover very extensive range of topics related to the development and characterization power/high voltage (HV) semiconductor technologies as well as modeling and simulations of the power/HV devices and smart power integrated circuits (ICs). Emphasis is placed on the practical applications of the advanced semiconductor technologies and the device level compact/spice modeling. This book is intended to provide reference information by selected, leading authorities in their domain of expertise. They are representing both academia and industry. All of them have been chosen because of their intimate knowledge of their subjects as well as their ability to present them in an easily understandable manner.