ESD in Silicon Integrated Circuits

Esd in Silicon Integrated Circuits Ajith Amerasekera Charvaka Duvvury Texas Instruments Inc, Dallas, USA Electrostatic Discharge (ESD) effects in silicon integrated circuits have become a major concern as today′s high circuit density technologies shrink to sub–micro dimensions. This book provides an understanding of the basic features related to ESD and deals with topics ranging from the physics of devices operating under ESD conditions to approaches for solving and improving ESD performance in advanced ICs. Features include: ∗ Description of the methods used to reproduce ESD–type events in a controlled test environment ∗ Analysis of the behavior of different semiconductor devices under ESD conditions, including the physics and modeling of devices ∗ Detailed study of design and layout requirements for ESD protection circuits ∗ Case studies showing examples of approaches to solving ESD design problems, including failure analysis Covering the state–of–the–art in circuit design for ESD prevention, this practical book is written from an industrial perspective and will appeal to engineers and scientists working in the fields of IC and transistor design. Researchers and advanced students in the fields of device/circuit modeling and semiconductor reliability, seeking to understand the fundamentals of ESD phenomena, will also find this book an invaluable reference source.

Preface 1. Introduction Background The ESD Problem Protecting against ESD Outline of the Book 2. ESD Phenomenon Introduction Electrostatic Voltage Discharge ESD Stress Models 3. Test Methods Introduction Human Body Model (HBM) Machine Model (MM) Charged Device Model (CDM) Socket Device Model (SDM) Metrology, Calibration, Verification Transmission Line Pulsing (TLP) Failure Criteria Summary 4 Physics and Operation of ESD Protection Circuits Introduction Resistors Diodes Transistor Operation Transistor Operation Under ESD Conditions Electrothermal Effects SCR Operation Conclusion 5 ESD Protection Design Concepts and Strategy The Qualities of Good ESD Protection ESD Protection Design Methods Selecting an ESD Strategy Summary 6 Design and Layout Requirements Introduction Thick Field Device NMOS Transistors (FPDs) Gate–Coupled NMOS (GCNMOS) Gate Driven nMOS (GDNMOS) SCR Protection Device ESD Protection Design Synthesis Total Input Protection ESD Protection Using Diode–Based Devices Power Supply Clamps BiPolar and BiCMOS Protection Circuits Summary 7 Advanced Protection Design Introduction PNP Driven NMOS (PDNMOS) Substrate Triggered NMOS (STNMOS) NMOS Triggered NMOS (NTNMOS) ESD for Mixed Voltage I/O CDM Protection SOI Technology High Voltage Transistors BiCMOS Protection RF Designs General I/O Protection Schemes Design/layout Errors Summary 8 Failure Modes, Reliability Issues, and Case Studies Introduction Failure Mode Analysis Reliability and Performance Considerations Advanced CMOS Input Protection Optimizing the Input Protection Scheme Designs for Special Applications Process Effects on Input Protection Design Total IC Chip Protection Power Bus Protection Internal Chip ESD Damage Stress Dependent ESD Behavior Failure Mode Case Studies Summary 9 Influence of Processing on ESD Introduction High Current Behavior Cross–section of a MOS Transistor Drain–Source Implant Effects P–Well Effects N–Well Effects Epitaxial Layers and Substrates Gate Oxides Silicides Contacts Interconnect and Metallization Gate Length Dependencies Silicon–On–Insulator (SOI) Bipolar Transistors Diodes Resistors Reliability Trade–Offs Summary 10 Device Modeling of High Current Effects Introduction The Physics of ESD Damage Thermal ("Second") Breakdown Analytical Models Using the Heat Equation Electrothermal Device Simulations Conclusions Circuit Simulation Basics, Approaches, and Simulations Introduction Modeling the MOSFET Modeling Bipolar Junction Transistors Modeling Diffusion Resistors Modeling Protection Diodes Simulation of Protection Circuits Electrothermal Circuit Simulations Conclusion 12 Conclusions Long–term Relevance of ESD in ICs State–of–the–art for ESD Protection Current Limitations Future Issues