Tutorials2002



	*2002 IRPS TUTORIAL PROGRAM*

	Chair: Tom Moore, Omniprobe, Inc. Vice Chair: Chris L. Henderson, Sandia National Labs Vice Chair: Cheryl Hartfield, Texas Instruments
		Topic 111. Introduction to Semiconductor Reliability Tim Rost and Vijay Reddy, Texas Instruments As increasing investments are made in VLSI technology and development, it becomes essential that semiconductor processes and IC designs have reliability issues addressed prior to volume manufacturing. Ideally, reliability issues would be addressed and corrected during the design process. This tutorial provides the motivation for understanding semiconductor reliability issues, a basic review of reliability wearout mechanisms, a discussion of how reliability mechanisms can be checked and corrected in the design phase, and how process technologies such as Cu interconnects and low-K dielectrics influence reliability design guidelines. This tutorial will provide the foundation to allow you to build technical depth in the areas of specific interest throughout the rest of the symposium. Topic 112. Characterization, Physical Modeling and Assessment of Gate Oxide Reliability Eric M. Vogel, National Institute of Standards and Technology An overview of past and present oxide reliability characterization techniques and degradation physics will be presented. This overview will provide a background in the physics, statistics, models, and characterization methodologies necessary for understanding the reliability issues present in current technology ultra-thin gate oxides. Topic 113. ESD Basics Charvaka Duvurry, Texas Instruments This presentation will provide an understanding of the ESD phenomena and the impact on IC circuit reliability. In addition, it will provide an insight into the future reliability issues for ESD. Topic 121.01 Soft Errors in Commercial Semiconductor Technology: Overview and Scaling Trends Robert Baumann, Texas Instruments We will examine the three radiation mechanisms responsible for soft errors and see how these sources can be quantified and their impact predicted. We will consider scaling trends in soft error performance and conclude by touching on common design and process strategies used to reduce soft error rate. Topic 121.02 Memory Devices Share of System SER Guenter Schindlbeck, Infineon Technologies What do soft errors look like at the data pins of memory components? We will show how this is influenced by the structure of the devices, and cover results of accelerated tests and system tests for soft errors. Finally the trend of decreasing SER for the last 8 generations of DRAMs is also shown. Topic 121.03 Accelerated Testing For Cosmic Ray Soft-Error Rates In Computer Systems Richard Adkisson, Hewlett Packard This presentation describes accelerated radiation testing experiments performed to investigate cosmic ray soft errors in memory systems. A description of cosmic ray induced memory problems from single and multi-bit errors is presented as well as the implications of those problems on system design

Topic 121.04
Impact of Technology Scaling and Logic Design Style on the Core Logic SER of Microprocessors
Norbert Seifert, Compact Computers

Recent studies have shown that the core logic of microprocessors is becoming increasingly susceptible to single event upsets and can no longer be neglected. This talk analyzes the impact of technology scaling and internal logic design on the soft error rates at the device, circuit, and system levels.

Topic 121.05
Low Activity Alpha Particle Detection
Mike Tucker,Alpha Sciences Inc.

Alpha particles from IC materials are known to cause SEU in semiconductor devices. Since 1978, the semiconductor industry has had to find accurate techniques for measuring these naturally occurring trace amounts of alpha emitting contaminants. This talk discusses some common metrology methods, with emphasis on gas flow proportional counters.

Topic 121.06
New Method for Determining Ultra Low Alpha Emission Levels
Rhys Thomas, Inovatia Labs

Alpha emission surface counting techniques are limited by analysis times and detection limits. Inovatia Laboratories has developed a method for the semiconductor industry that will achieve the equivalent of 0.002 cph/cm2 in 4 hours. The user may achieve lower detection limits by manipulating sample sizes and counting times.

Topic 121.07
CMOS Soft Errors and Server Design
Douglas Bossen, IBM

The occurrence of soft errors in today's CMOS technology is at odds with the high availability requirements of server customers. This presentation will outline the design methodology and a variety of fault masking techniques that are in use in today's servers to eliminate the effect of soft errors.

Topic 121.08
A kind and gentler guide to Soft Error Rate
Hang Nguyen, Intel Corporation

With increasingly advanced process technology, the soft error (SER) susceptibility of ICs poses a formidable challenge to their reliability. This is especially true for mission critical applications. This talk will describe a systematic approach to help designers cope with SER using two basic steps: 1) SER estimation and 2) SER reduction techniques.

Topic 121.09
Memory SER Concerns For Future Server Applications
Charles Slayman, Sun Microsystems

Server designers need to know the type and rate of errors that will occur in order to design systems that meet the reliability/accessibility/ serviceability requirements. A discussion of the needs of server designers and the design trade-offs that must be made to prevent cost or performance penalties will be presented.

Topic 121.10
Comparison of Soft Errors in Protected and Unprotected Processors
Peter Rohr, iROC Technologies

Soft error vulnerability for memories is established. Now, the logic part of chips is just as vulnerable, receiving attention by relatively few. Protection of logic is different from memories. We will demonstrate radiation test results for a SPARC chip with and without protection demonstrating sensitivity to and protection from soft errors.

Topic 121.11
Mitigation Methods for Soft-Errors and Related Phenomena in Spacecraft
Allan Johnston, Jet Propulsion Laboratory

Energetic particles in space produce soft errors and other effects in microelectronics. Methods to deal with this include error detection and correction, power cycling, and operational methods. This paper discusses these techniques, including real examples where they have been applied, along with cases where unexpected responses have caused electronic malfunctions.



	Topic 121.12 Mitigation of Single-Event effects in Mission-Critical Systems Paul E. Dodd and Fred W. Sexton, Sandia National Laboratories Techniques for mitigation of single-event upset, latchup, and gate rupture/burnout will be presented. Mitigation options include component-level technology solutions, hardened circuit designs, and fault-tolerant system architectures. Examples of each of these techniques will be given, and the impact of technology trends on the feasibility of mitigation solutions will be discussed. Topic 131. Errors and Reliability Kristof Croes, XPEQT, and Luc Tielemans Standard reliability testing is done using the “time to failure” test methodology. Over the error budget, the problems of this method and the influences of the inaccuracy of e.g. stress conditions and the influences of sample differences will be demonstrated. Optimisation of the "time to failure" methodology and alternative techniques and possibilities will be discussed. Topic 132. Trends in Failure Analysis Larry Wagner, Texas Instruments Topic 133. New Phenomena in the Device Reliability Physics of Advanced Submicron CMOS Technologies (NBTI) Giuseppe La Rosa, IBM This tutorial will give an overview of some of the new reliability phenomena observed in MOSFET devices of advanced submicron CMOS technologies and their impact to reliability lifetime projections. Some focus will be given to Hot Carrier Reliability Phenomena such as e-e scattering, secondary impact ionization as well as parasitic drain series resistance effects in NMOSFET as well as hot hole damage in PMOSFET devices. In addition the role of Negative Bias Temperature Instabilites (NBTI) as technology limiter in the design of PMOSFET submicron devices will be discussed. The impact of these phenomena to DC and AC based circuit lifetime projections as well as methodologies will be given. Topic 141. The basics of Electromigration with a view towards Cu dual-damascene reliability E. T. Ogawa, Texas Instruments, Inc. Electromigration (EM) has been a major interconnect reliability concern from the early days of integrated circuit technology. This tutorial will describe EM in the context of Al-based technology and lead into present day concerns and new techniques about assessing interconnect reliability, especially in the case of Cu dual-damascene interconnects. Some topics to be discussed will include the Blech effect, mass transport pathways, and early failure. Topic 142. Introduction to Predictive Wafer Level Reliability E. S. Snyder, Sandia Technologies Assuring IC reliability is even more challenging today with new materials and higher than ever levels of material stress. Wafer Level Reliability (WLR) is one tool that can help meet this challenge. Traditional WLR approaches have emphasized test speed over quality of data. This tutorial will introduce Predictive WLR and show how proper attention to the underlying reliability physics can yield WLR that provides quantitative data similar to packaged-level tests in a much shorter time. This predictive WLR supports process monitoring, rapid qualification and development. We describe the theoretical approach needed to maximize the quality of WLR data with examples of Cu/low-k electromigration and vias, ultra-thin oxide breakdown, deep submicron hot-carriers, plasma damage and mobile ions. These technical examples show the features and utility of a WLR that is optimized for predictability and not just speed. Topic 143. Defect Reliability Statistics with Redundancy Glenn Shirley, Intel Defect Reliability Statistics with Redundancy Power and intrinsic wearout have begun to limit the effectiveness and increase the costs of burn-in for high-performance silicon processes. This tutorial covers approaches and models useful in controlling infant mortality today. Power management in burn-in, fault-tolerant chip design, population slicing, etc. will be discussed.

Topic 211.
Reliability Issues for Advanced Silicon Technologies
Anthony S. Oates, Agere

Silicon technology evolution continues at an increasing pace. The need for improved circuit performance and ever-higher levels of circuit integration necessitate aggressive feature size scaling and the introduction into the manufacturing environment of novel materials. In the process, existing materials are being pushed to their physical and electrical limits while the long-term implications of the use of newer materials are not fully understood. One of the major concerns for future technology development is the maintenance of the high level of reliability that the industry has attained. This course will provide an overview of the major silicon - related reliability issues for advanced semiconductor technologies. The emphasis of this course will be on the physical understanding of failure modes relevant to the advanced transistor structures and new materials used in the latest generations of silicon integrated circuit technology.

Topic 212.
Microstructure, Processing and Reliability of Cu-Based Interconnect Structures
John Sanchez, AMD

The implementation of Cu-based interconnect structures is the result of the development of novel processing schemes and the learning of new paradigms for structure-processing relationships, as well the application of relevant portions of the existing Al-based interconnect knowledge foundation. As an example, the challenging tight pitch metallization schemes for 130 nm generation technologies and beyond, require novel damascene patterning of Cu-filled trenches filled by bottom-up electroplating. The stringent Cu diffusion barrier and electroplating requirements dictate refractory metal and Cu "seed" layers, however experience learned during Al-based multilayer metallization development may be applied to barrier metal/Cu interconnect process development. In addition, basic materials' properties and processing effects will also determine the mechanisms controlling Cu interconnect reliability, although the degree to which individual mechanisms may vary since typical Cu microstructures and mechanical properties vary from typical Al-based structures. This tutorial will describe the key factors that control Cu interconnect reliability: interconnect microstructure and the dependence on processing schemes; mechanical stresses and the dependence on dielectric constraint and thermal processing; and diffusional mechanisms that determine stress evolution, voiding, delamination and interconnect failure.

Topic 213.
ESD PROTECTION AND FAILURE MECHANISMS IN RF TECHNOLOGY
Steven Voldman, IBM

With the growth and performance objectives of the radio frequency (RF) applications in the semiconductor industry, electrostatic discharge (ESD) sensitivity is playing an important role as these new technologies and products become mainstream in today's GHz electronic world. This tutorial will discuss ESD physics, devices, circuits and failure mechanisms in RF technology from early technology development to modern devices in this millennium. Failure mechanisms, latency effects, and testing techniques will also be discussed. ESD robustness and failure mechanisms of RF CMOS, Silicon Germanium, Silicon Germanium Carbon, Gallium Arsenide and RF SOI will be discussed.

Topic 221.
GATE OXIDE RELIABILITY
Paul Nicollian, Texas Instruments

We review the effects of voltage and thickness scaling on dielectric reliability breakdown models and mechanisms. The understanding and progress in exploiting breakdown physics for improving reliability margins are discussed.

Topic 222.
ANTENNA CHARGING (PID)
Srikanth Krishnan and Anand Krishnan, Texas Instruments, Inc.

Topic 223.
Atomic Scale Defects Involved in MOS Reliability Problems
Pat Lenahan, Penn State

Although imperfect and incomplete, a fundamental understanding of many of the atomic scale defects involved in important MOS reliability problems now exists. This understanding comes primarily from electron spin resonance (ESR) and statistical mechanics. I'll introduce both (ESR) and statistical mechanics and discuss the most important defects.

Topic 224.
TRAP GENERATION PHENOMENA IN THIN DIELECTRICS UNDER ELECTRICAL STRESS
Gennadi Bersuker, SEMATECH

Aggressive device scaling calls for gate dielectrics with smaller effective oxide thickness and raises concerns about their reliability. So far, extensive research efforts to identify the key factor controlling degradation of SiO₂ films have not yielded a comprehensive model, while our understanding of the high-k materials is even further away. This tutorial provides high-level overview/analysis of the conventional oxide degradation models and discusses an alternative mechanism for defect generation. Defect formation is considered at an atomic level as a multi-step phenomenon subsequently involving several physical and chemical processes. Applications to high-k dielectrics are discussed.

Topic 231.
RAMAN SPECTROSCOPY
Ingrid DeWolf, IMEC

This tutorial addresses the unique application possibilities of Raman spectroscopy for microelectronics. After a short introduction on the Raman spectroscopy theory, the instrumentation is explained, including spatial resolution and confocality. Next examples are given where Raman spectroscopy is used for the study of composition, doping, crystallinity, phase, temperature and mechanical stress. These examples cover different materials, such as Si, InSb, SiGe, AlGaAs, diamond, and silicides. The main focus of this tutorial will be on the use of Raman spectroscopy to study local mechanical stress. Examples are given for stress introduced by isolation (LOCOS, shallow trench, deep trench) and silicidation,. But also packaging related stress is discussed, such as near solder bumps are even in the whole packaged chip. This includes both one and two-dimensional stress maps. Finally, examples are given where the technique was used to study stress in MEMS, such as membranes.

Topic 232.
NEXT GENERATION IMAGING
Gay Samuelson, Intel

This tutorial will focus on the intrinsic and extrinsic defects in current and planned semiconductor package technologies that require imaging techniques to fault isolate and identify failure mechanisms prior to destructive analysis. . The techniques that will be discussed are x-ray radiography/topography, scanning acoustic microscopy, scanning squid microscopy, time domain reflectometry, thermal and terahertz imaging. These tools and techniques will be discussed from the point of view of current capability and limitations and the general direction needed for future capability that is consistent with semiconductor packaging trends.

Topic 233.
DESIGNING MEMS/MEOMS FOR RELIABILITY
Susanne Arney et al., Lucent

This course will provide attendees with a basic working knowledge of how to design MEMS/MOEMS for reliability. The course will concentrate on MEMS design, reliability physics, MEMS-specific fundamental reliability phenomena and failure mechanisms, and accelerated testing protocols. Practical and useful examples from various arenas of MEMS application will be provided. LEARNING OUTCOMES This course will enable you to:
• Develop a design-for-reliability mentality
• Become fluent with the many aspects of MEMS reliability physics and failure mechanisms

• Learn how to efficiently construct a MEMS reliability test plan to expand beyond qualification-based knowledge

• Evaluate specific MEMS designs for reliability investigations

• Understand the importance of fundamental models of MEMS failure mechanisms in designing accelerated testing strategies

• Assess reliability test results to obtain truly robust MEMS designs.

INTENDED AUDIENCE Anyone who needs to learn how to design reliable MEMS. This course will be of value to those who either design their own MEMS or those who work directly or indirectly with MEMS designers. MEMS Materials, Fabrication, Packaging, Design, Reliability and Test engineers will benefit from this overview of MEMS Reliability physics.

Topic 241.
Silicon Analog/Mixed Signal Technology Reliability
Jae-Sung Rieh & Fernando Guarin, IBM

A review on the reliability of analog/mixed signal technologies is provided with SiGe BiCMOS as an example. The forward and reverse mode reliability of SiGe HBTs are discussed as well as CMOS reliability focused on analog applications. Reliability issues for passive components such as capacitors, resistors, and inductors are also reviewed.

Topic 242.
Ferroelectric Material and Device Reliability
Domokos Hadnagy, Ramtron

Topic 243.
DETERMINATION OF GaAs MMIC RELIABILITY
Ken Decker, TriQuint Semiconductor

Numerous aspects of the GaAs MMIC must be considered to accurately determine its reliability. Various common failure mechanisms for GaAs devices and methods of determining lifetime will be discussed. Example of accelerated life tests will be shown. The importance of proper channel temperature evaluation will be explained.

Topic 244.
GaAs -BASED HBT RELIABILITY
Tim Henderson, TriQuint Semiconductor

First, we will discuss the different failure modes and mechanisms responsible for HBT degradation. Next, we will cover a physics-based model that qualitatively and quantitatively describes GaAs HBT degradation. Finally, we will discuss the key parameters that affect reliability, through a description of recent results on InGaP-emitter HBTs.