Design And Characterization Of Novel Devices For New Generation Of Electrostatic Discharge Esd Protection Structures

This dissertation presents a comprehensive design methodology for implementing custom on-chip ESD protection structures in different commercial technologies. First, the ESD topic in the semiconductor industry is revised, as well as ESD standards and commonly used schemes to provide ESD protection in ICs. The general ESD protection approaches are illustrated and discussed using different types of protection components and the concept of the ESD design window.

Technology Computer Aided Design (TCAD) and Simulation Program with Integrated Circuit Emphasis (SPICE) simulation is widely used in ESD protection design. In this dissertation, TCAD and SPICE simulation are carried out for a few times for both of pre-tapeout evaluation on characteristics of the proposed device and circuit and post-tapeout analysis on structure operating mechanism.

ESD Protection Device and Circuit Design for Advanced CMOS Technologies is intended for practicing engineers working in the areas of circuit design, VLSI reliability and testing domains. As the problems associated with ESD failures and yield losses become significant in the modern semiconductor industry, the demand for graduates with a basic knowledge of ESD is also increasing. Today, there is a significant demand to educate the circuits design and reliability teams on ESD issues. This book makes an attempt to address the ESD design and implementation in a systematic manner. A design procedure involving device simulators as well as circuit simulator is employed to optimize device and circuit parameters for optimal ESD as well as circuit performance. This methodology, described in ESD Protection Device and Circuit Design for Advanced CMOS Technologies has resulted in several successful ESD circuit design with excellent silicon results and demonstrates its strengths.

Electrostatic discharge (ESD) is one of the most prevalent threats to electronic components. In an ESD event, a finite amount of charge is transferred from one object (i.e., human body) to another (i.e., microchip). This process can result in a very high current passing through the microchip within a very short period of time. Thus, more than 35 percent of single-event chip damages can be attributed to ESD events, and designing ESD structures to protect integrated circuits against the ESD stresses is a high priority in the semiconductor industry. Electrostatic Discharge Protection: Advances and Applications delivers timely coverage of component- and system-level ESD protection for semiconductor devices and integrated circuits. Bringing together contributions from internationally respected researchers and engineers with expertise in ESD design, optimization, modeling, simulation, and characterization, this book bridges the gap between theory and practice to offer valuable insight into the state of the art of ESD protection. Amply illustrated with tables, figures, and case studies, the text: Instills a deeper understanding of ESD events and ESD protection design principles Examines vital processes including Si CMOS, Si BCD, Si SOI, and GaN technologies Addresses important aspects pertinent to the modeling and simulation of ESD protection solutions Electrostatic Discharge Protection: Advances and Applications provides a single source for cutting-edge information vital to the research and development of effective, robust ESD protection solutions for semiconductor devices and integrated circuits.

Electrostatic Discharge (ESD) is a significant hazard to electronic components and systems. Based on a specific processing technology, a given circuit application requires a customized ESD consideration that includes the devices' operating voltage, leakage current, breakdown constraints, and footprint. As new technology nodes mature every 3-5 years, design of effective ESD protection solutions has become more and more challenging due to the narrowed design window, elevated electric field and current density, as well as new failure mechanisms that are not well understood. The endeavor of this research is to develop novel, effective and robust ESD protection solutions for both emerging technologies and modern complementary metal-oxide-semiconductor (CMOS) technologies. The Si nanowire field-effect transistors are projected by the International Technology Roadmap for Semiconductors as promising next-generation CMOS devices due to their superior DC and RF performances, as well as ease of fabrication in existing Silicon processing. Aiming at proposing ESD protection solutions for nanowire based circuits, the dimension parameters, fabrication process, and layout dependency of such devices under Human Body Mode (HBM) ESD stresses are studied experimentally in company with failure analysis revealing the failure mechanism induced by ESD. The findings, including design methodologies, failure mechanism, and technology comparisons should provide practical knowhow of the development of ESD protection schemes for the nanowire based integrated circuits. Organic thin-film transistors (OTFTs) are the basic elements for the emerging flexible, printable, large-area, and low-cost organic electronic circuits. Although there are plentiful studies focusing on the DC stress induced reliability degradation, the operation mechanism of OTFTs subject to ESD is not yet available in the literature and are urgently needed before the organic technology can be pushed into consumer market. In this work, the ESD operation mechanism of OTFT depending on gate biasing condition and dimension parameters are investigated by extensive characterization and thorough evaluation. The device degradation evolution and failure mechanism under ESD are also investigated by specially designed experiments. In addition to the exploration of ESD protection solutions in emerging technologies, efforts have also been placed in the design and analysis of a major ESD protection device, diode-triggered-silicon-controlled-rectifier (DTSCR), in modern CMOS technology (90nm bulk). On the one hand, a new type DTSCR having bi-directional conduction capability, optimized design window, high HBM robustness and low parasitic capacitance are developed utilizing the combination of a bi-directional silicon-controlled-rectifier and bi-directional diode strings. On the other hand, the HBM and Charged Device Mode (CDM) ESD robustness of DTSCRs using four typical layout topologies are compared and analyzed in terms of trigger voltage, holding voltage, failure current density, turn-on time, and overshoot voltage. The advantages and drawbacks of each layout are summarized and those offering the best overall performance are suggested at the end.

Electrostatic Discharge is a pervasive issue in the semiconductor industry affecting both manufacturers and users of semiconductors. This easy-to-read, practical handbook presents an overview of ESD as it effects electronic circuits and provides a concise introduction for students, engineers, circuit designers and failure analysts.

Electrostatic discharge (ESD) is defined as the transfer of charge between bodies at different potentials. The electrostatic discharge induced integrated circuit damages occur throughout the whole life of a product from the manufacturing, testing, shipping, handing, to end user operating stages. This is particularly true as microelectronics technology continues shrink to nano-metric dimensions. The ESD related failures is a major IC reliability concern and results in a loss of millions dollars to the semiconductor industry each year. Several ESD stress models and test methods have been developed to reproduce the real world ESD discharge events and quantify the sensitivity of ESD protection structures. The basic ESD models are: Human body model (HBM), Machine model (MM), and Charged device model (CDM). To avoid or reduce the IC failure due to ESD, the on-chip ESD protection structures and schemes have been implemented to discharge ESD current and clamp overstress voltage under different ESD stress events. Because of its simple structure and good performance, the junction diode is widely used in on-chip ESD protection applications. This is particularly true for ESD protection of low-voltage ICs where a relatively low trigger voltage for the ESD protection device is required. However, when the diode operates under the ESD stress, its current density and temperature are far beyond the normal conditions and the device is in danger of being damaged. For the design of effective ESD protection solution, the ESD robustness and low parasitic capacitance are two major concerns. The ESD robustness is usually defined after the failure current It2 and on-state resistance Ron. The transmission line pulsing (TLP) measurement is a very effective tool for evaluating the ESD robustness of a circuit or single element. This is particularly helpful in characterizing the effect of HBM stress where the ESD-induced damages are more likely due to thermal failures. Two types of diodes with different anode/cathode isolation technologies will be investigated for their ESD performance: one with a LOCOS (Local Oxidation of Silicon) oxide isolation called the LOCOS-bound diode, the other with a polysilicon gate isolation called the polysilicon-bound diode. We first examine the ESD performance of the LOCOS-bound diode. The effects of different diode geometries, metal connection patterns, dimensions and junction configurations on the ESD robustness and parasitic capacitance are investigated experimentally. The devices considered are N+/P-well junction LOCOS-bound diodes having different device widths, lengths and finger numbers, but the approach applies generally to the P+/N-well junction diode as well. The results provide useful insights into optimizing the diode for robust HBM ESD protection applications. Then, the current carrying and voltage clamping capabilities of LOCOS- and polysilicon-bound diodes are compared and investigated based on both TCAD simulation and experimental results. Comparison of these capabilities leads to the conclusion that the polysilicon-bound diode is more suited for ESD protection applications due to its higher performance. The effects of polysilicon-bound diode's design parameters, including the device width, anode/cathode length, finger number, poly-gate length, terminal connection and metal topology, on the ESD robustness are studied. Two figures of merits, FOM_It2 and FOM_Ron, are developed to better assess the effects of different parameters on polysilicon-bound diode's overall ESD performance. As latest generation package styles such as mBGAs, SOTs, SC70s, and CSPs are going to the millimeter-range dimensions, they are often effectively too small for people to handle with fingers. The recent industry data indicates the charged device model (CDM) ESD event becomes increasingly important in today's manufacturing environment and packaging technology. This event generates highly destructive pulses with a very short rise time and very small duration. TLP has been modified to probe CDM ESD protection effectiveness. The pulse width was reduced to the range of 1-10 ns to mimic the very fast transient of the CDM pulses. Such a very fast TLP (VFTLP) testing has been used frequently for CDM ESD characterization. The overshoot voltage and turn-on time are two key considerations for designing the CDM ESD protection devices. A relatively high overshoot voltage can cause failure of the protection devices as well as the protected devices, and a relatively long turn-on time may not switch on the protection device fast enough to effectively protect the core circuit against the CDM stress. The overshoot voltage and turn-on time of an ESD protection device can be observed and extracted from the voltage versus time waveforms measured from the VFTLP testing. Transient behaviors of polysilicon-bound diodes subject to pulses generated by the VFTLP tester are characterized for fast ESD events such as the charged device model. The effects of changing devices' dimension parameters on the transient behaviors and on the overshoot voltage and turn-on time are studied. The correlation between the diode failure and poly-gate configuration under the VFTLP stress is also investigated. Silicon-controlled rectifier (SCR) is another widely used ESD device for protecting the I/O pins and power supply rails of integrated circuits. Multiple fingers are often needed to achieve optimal ESD protection performance, but the uniformity of finger triggering and current flow is always a concern for multi-finger SCR devices operating under the post-snapback region. Without a proper understanding of the finger turn-on mechanism, design and realization of robust SCRs for ESD protection applications are not possible. Two two-finger SCRs with different combinations of anode/cathode regions are considered, and their finger turn-on uniformities are analyzed based on the I-V characteristics obtained from the transmission line pulsing (TLP) tester. The dV/dt effect of pulses with different rise times on the finger turn-on behavior of the SCRs are also investigated experimentally. In this work, unless noted otherwise, all the measurements are conducted using the Barth 4002 transmission line pulsing (TLP) and Barth 4012 very-fast transmission line pulsing (VFTLP) testers.

This book addresses key aspects of analog integrated circuits and systems design related to system level electrostatic discharge (ESD) protection. It is an invaluable reference for anyone developing systems-on-chip (SoC) and systems-on-package (SoP), integrated with system-level ESD protection. The book focuses on both the design of semiconductor integrated circuit (IC) components with embedded, on-chip system level protection and IC-system co-design. The readers will be enabled to bring the system level ESD protection solutions to the level of integrated circuits, thereby reducing or completely eliminating the need for additional, discrete components on the printed circuit board (PCB) and meeting system-level ESD requirements. The authors take a systematic approach, based on IC-system ESD protection co-design. A detailed description of the available IC-level ESD testing methods is provided, together with a discussion of the correlation between IC-level and system-level ESD testing methods. The IC-level ESD protection design is demonstrated with representative case studies which are analyzed with various numerical simulations and ESD testing. The overall methodology for IC-system ESD co-design is presented as a step-by-step procedure that involves both ESD testing and numerical simulations.

An authoritative single-volume reference on the design and analysis of ESD protection for ICs Electrostatic discharge (ESD) is a major reliability challenge to semiconductors, integrated circuits (ICs), and microelectronic systems. On-chip ESD protection is a vital to any electronic products, such as smartphones, laptops, tablets, and other electronic devices. Practical ESD Protection Design provides comprehensive and systematic guidance on all major aspects of designs of on-chip ESD protection for integrated circuits (ICs). Written for students and practicing engineers alike, this one-stop resource covers essential theories, hands-on design skills, computer-aided design (CAD) methods, characterization and analysis techniques, and more on ESD protection designs. Detailed chapters examine an array of topics ranging from fundamental to advanced, including ESD phenomena, ESD failure analysis, ESD testing models, ESD protection devices and circuits, ESD design layout and technology effects, ESD design flows and co-design methods, ESD modelling and CAD techniques, and future ESD protection concepts. Based on the author’s decades of design, research and teaching experiences, Practical ESD Protection Design: • Features numerous real-world ESD protection design examples • Emphasizes on ESD protection design techniques and procedures • Describes ESD-IC co-design methodology for high-performance mixed-signal ICs and broadband radio-frequency (RF) ICs • Discusses CAD-based ESD protection design optimization and prediction using both Technology and Electrical Computer-Aided Design (TCAD/ECAD) simulation • Addresses new ESD CAD algorithms and tools for full-chip ESD physical design verification • Explores the disruptive future outlook of ESD protection Practical ESD Protection Design is a valuable reference for industrial engineers and academic researchers in the field, and an excellent textbook for electronic engineering courses in semiconductor microelectronics and integrated circuit designs.