Richard Ulrich

Integrated passive component technology

Contributors.Preface.1 Introduction (Richard K. Ulrich).1.1 Status and Trends in Discrete Passive Components.1.2 Definitions and Configurations of Integrated Passives.1.3 Comparison to Integrated Active Devices.1.4 Substrates and Interconnect Systems for Integrated Passives.1.5 Fabrication of Integrated Passives.1.6 Reasons for Integrating Passive Devices.1.7 Problems with Integrating Passive Devices.1.8 Applications for Integrated Passives.1.9 The Past and Future of Integrated Passives.1.10 Organization of this Book.References.2 Characteristics and Performance of Planar Resistors (Richard K. Ulrich).2.1 Performance Parameters.2.2 Resistance in Electronic Materials.2.3 Sizing Integrated Resistors.2.4 Trimming.References.3 Integrated Resistor Materials and Processes (Richard K. Ulrich).3.1 Single-Component Metals.3.2 Metal Alloys and Metal-Nonmetal Compounds.3.3 Semiconductors.3.4 Cermets.3.5 Polymer Thick Film.3.6 Ink Jet Deposition.3.7 Commercialized Processes.3.8 Summary.References.4 Dielectric Materials for Integrated Capacitors (Richard K. Ulrich).4.1 Polarizability and Capacitance.4.2 Capacitance Density.4.3 Temperature Effects.4.4 Frequency and Voltage Effects.4.5 Aging Effects.4.6 Composition and Morphology Effects.4.7 Leakage and Breakdown.4.8 Dissipation Factor.4.9 Comparison to EIA Dielectric Classifications.4.10 Matching Dielectric Materials to Applications.References.5 Size and Configuration of Integrated Capacitors (Richard K. Ulrich).5.1 Comparison of Integrated and Discrete Areas.5.2 Layout Options.5.3 Tolerance.5.4 Mixed Dielectric Strategies.5.5 CV Product.5.6 Maximum Capacitance Density and Breakdown Voltage.References.6 Processing Integrated Capacitors (Richard K. Ulrich).6.1 Sputtering.6.2 CVD, PECVD and MOCVD.6.3 Anodization.6.4 Sol-Gel and Hydrothermal Ferroelectrics.6.5 Thin- and Thick-Film Polymers.6.6 Thick-Film Dielectrics.6.7 Interlayer Insulation.6.8 Interdigitated Capacitors.6.9 Capacitor Plate Materials.6.10 Trimming Integrated Capacitors.6.11 Commercialized Integrated Capacitor Technologies.6.12 Summary.References.7 Defects and Yield Issues (Richard K. Ulrich).7.1 Causes of Fatal Defects in Integrated Capacitors.7.2 Measurement of Defect Density.7.3 Defect Density and System Yield.7.3.1 Predicting Yield from Defect Density.7.4 Yield Enhancement Techniques for Capacitors.7.5 Conclusions.References.8 Electrical Performance of Integrated Capacitors (Richard K. Ulrich and Leonard W. Schaper).8.1 Modeling Ideal Passives.8.2 Modeling Real Capacitors.8.3 Electrical Performance of Discrete and Integrated Capacitors.8.4 Dissipation Factor of Real Capacitors.8.5 Measurement of Capacitor Properties.8.6 Summary.References.9 Decoupling (Leonard W. Schaper).9.1 Power Distribution.9.2 Decoupling with Discrete Capacitors.9.3 Decoupling with Integrated Capacitors.9.4 Dielectrics and Configurations for Integrated Decoupling.9.5 Integrated Decoupling as an Entry Application.References.10 Integrated Inductors (Geert J. Carchon and Walter De Raedt).10.1 Introduction.10.2 Inductor Behavior and Performance Parameters.10.3 Inductor Performance Prediction.10.4 Integrated Inductor Examples.10.5 Use of Inductors in Circuits: Examples.10.6 Conclusions.Acknowledgments.References.11 Modeling of Integrated Inductors and Resistors for Microwave Applications (Zhenwen Wang, M. Jamal Deen, and A. H. Rahal).11.1 Introduction.11.2 Modeling of Spiral Inductors.11.3 Modeling of Thin-Film Resistors.11.4 Conclusions.References.Appendix: Characteristics of Microscript Lines.12 Other Applications and Integration Technologies (Elizabeth Logan, Geert J. Carchon, Walter De Raedt, Richard K. Ulrich, and Leonard W. Schaper).12.1 Demonstration Devices Fabricated with Integrated Passives.12.2 Commercialized Thin-Film Build-Up Integrated Passives.12.3 Other Integrated Passive Technologies.12.4 Summary.Acknowledgments.References.13 The Economics of Embedded Passives (Peter A. Sandborn).13.1 Introduction.13.2 Modeling Embedded Passive Economics.13.3 Key Aspects of Modeling Embedded Passive Costs.13.4 Example Case Studies.13.5 Summary.Acknowledgments.References.14 The Future of Integrated Passives (Richard K. Ulrich).14.1 Status of Passive Integration.14.2 Issues for Implementation on Organic Substrates.14.3 Progress on Board-Level Implementation.14.4 Three Ways In for Organic Boards.14.5 Conclusion.Index.About the Editors.

Advanced electronic packaging

Chapter 1: Introduction and overview of microelectronic packaging. Chapter 2: Materials for microelectronic packaging. Chapter 3: Processing technologies. Chapter 4: Organic printed circuit board materials and processes. Chapter 5: Ceramic substrates. Chapter 6: Electrical considerations, modeling, and simulation. Chapter 7: Thermal considerations. Chapter 8: Mechanical design considerations. Chapter 9: Discrete and embedded passive devices. Chapter 10: Electronic package assembly. Chapter 11: Design considerations. Chapter 12: Radio frequency and microwave packaging. Chapter 13: Power electronics packaging. Chapter 14: Multichip and three-dimensional packaging. Chapter 15: Packaging of MEMS and MOEMS: challenges and a case study. Chapter 16: Reliability considerations. Chapter 17: Cost evaluation and analysis. Chapter 18: Analytical techniques for materials characterization.

Growth of Serratia liquefaciens under 7 mbar, 0°C, and CO2-Enriched Anoxic Atmospheres

Twenty-six strains of 22 bacterial species were tested for growth on trypticase soy agar (TSA) or sea-salt agar (SSA) under hypobaric, psychrophilic, and anoxic conditions applied singly or in combination. As each factor was added to multi-parameter assays, the interactive stresses decreased the numbers of strains capable of growth and, in general, reduced the vigor of the strains observed to grow. Only Serratia liquefaciens strain ATCC 27592 exhibited growth at 7 mbar, 0°C, and CO2-enriched anoxic atmospheres. To discriminate between the effects of desiccation and hypobaria, vegetative cells of Bacillus subtilis strain 168 and Escherichia coli strain K12 were grown on TSA surfaces and simultaneously in liquid Luria-Bertani (LB) broth media. Inhibition of growth under hypobaria for 168 and K12 decreased in similar ways for both TSA and LB assays as pressures were reduced from 100 to 25 mbar. Results for 168 and K12 on TSA and LB are interpreted to indicate a direct low-pressure effect on microbial growth with both species and do not support the hypothesis that desiccation alone on TSA was the cause of reduced growth at low pressures. The growth of S. liquefaciens at 7 mbar, 0°C, and CO2-enriched anoxic atmospheres was surprising since S. liquefaciens is ecologically a generalist that occurs in terrestrial plant, fish, animal, and food niches. In contrast, two extremophiles tested in the assays, Deinococcus radiodurans strain R1 and Psychrobacter cryohalolentis strain K5, failed to grow under hypobaric (25 mbar; R1 only), psychrophilic (0°C; R1 only), or anoxic (< 0.1% ppO2; both species) conditions.

Embedded resistors and capacitors for organic-based SOP

System-on-package (SOP) architectures take advantage of compact, high-performance designs to place the maximum amount of functionality on a subsystem that can then be mounted on a lower-cost, lower density interconnect board. Embedding passive components is a key technology in achieving these goals since this enables smaller SOP substrate footprints or, equivalently, higher functional density, along with better power distribution, increased design flexibility and improved reliability. The resulting footprint areas of integrating capacitors will have more of an effect on the layer count of SOP assemblies than will integrating resistors due to the rather low specific capacitances of most embeddable dielectrics, but the situation is improving steadily. It may be necessary to use two different dielectric materials to cover the entire required range. The inherently lower parasitic inductance of embedded capacitors makes them much more useful in decoupling than surface mount capacitors, enabling more robust power distribution and decreased power/ground noise. The key to this performance enhancement in large boards is the use of a thin dielectric to decrease the inductance but, for the smaller SOP substrates, the dielectric constant must also be high to provide sufficient decoupling capacitance in the reduced area.

Matching embedded capacitor dielectrics to applications

All capacitor dielectric materials, whether used for discrete or embedded applications, can be grouped into two general categories: paraelectric and ferroelectric. Ferroelectrics generally exhibit much higher dielectric constants, but are also less stable with regard to temperature, frequency, voltage, time and film thickness. There are dozens of each of these materials that have been used in discrete capacitors and about ten that are either available for use in embedded capacitors or will soon be marketed for that purpose. The commercialized materials can be broken down into four sub‐categories: thick‐film polymers, ferroelectric powder in polymer binders, thin‐film paraelectrics, and thick‐film ferroelectrics. These four classifications are evaluated with regard to their electrical performance, ease of fabrication, and suitability for specific applications.

Dynamic Temperature Fields under Mars Landing Sites and Implications for Supporting Microbial Life

While average temperatures on Mars may be too low to support terrestrial life-forms or aqueous liquids, diurnal peak temperatures over most of the planet can be high enough to provide for both, down to a few centimeters beneath the surface for some fraction of the time. A thermal model was applied to the Viking 1, Viking 2, Pathfinder, Spirit, and Opportunity landing sites to demonstrate the dynamic temperature fields under the surface at these well-characterized locations. A benchmark temperature of 253 K was used as a lower limit for possible metabolic activity, which corresponds to the minimum found for specific terrestrial microorganisms. Aqueous solutions of salts known to exist on Mars can provide liquid solutions well below this temperature. Thermal modeling has shown that 253 K is reached beneath the surface at diurnal peak heating for at least some parts of the year at each of these landing sites. Within 40 degrees of the equator, 253 K beneath the surface should occur for at least some fraction of the year; and, within 20 degrees , it will be seen for most of the year. However, any life-form that requires this temperature to thrive must also endure daily excursions to far colder temperatures as well as periods of the year where 253 K is never reached at all.

PECVD silicon and nitride postbond films for protecting bondpads, bonds and bondwires from corrosion failure

It was demonstrated experimentally that the ultimate strain of PECVD thin-film silicon nitride coatings increased as the films were made thinner, giving them better mechanical properties for protecting underlying bulk Al structures such as bondwires, bond, and bondpads. In sections of under a micron, the films did not crack over Al bonds or bondwires during standard industrial temperature cycling. Temperature ramping tests indicated that 1000-A films had at least three times the ultimate strain expected from bulk values. Film thickness was consistent around bondwires and in the vicinity of the bonds from the plasma deposition. The most susceptible part of the films was the area in the occluded cavity under the foot of the bond. The spread of Al metallization corrosion under these films proceeded at a slower rate than the thinner films due to their more favorable mechanical properties. The results of this project indicate that PECVD silicon nitride films are good candidates as protective films for mounted and bonded microelectronic or hybrid devices and have the potential of outperforming polymeric films by a wide margin.<<ETX>>

High capacitance density thin film integrated tantalum pentoxide decoupling capacitors

The process development and analysis of a multilayered thin film integrated capacitor is presented. Thin film integrated capacitors show great promise as IC power supply decoupling capacitors. Their low intrinsic inductance allows them to deliver fast switching high currents to the IC. However, current thin film capacitors are limited in capacitance due to the limitation of substrate area in boards or packages. Generally, there is not enough area available to produce the capacitance needed so that integrated capacitors can completely replace discretes. In this paper a multilayer thin film integrated capacitor design was discussed. The details of the multilayer process was described, as well as process challenges and preliminary results of the research. Currently capacitance densities in the range of 0.4 /spl mu/P/cm/sup 2/ have been obtained with a two layer process.

Potentiostatic testing of plasma-deposited silicon nitride thin protective films for bonds, bondwires and bondpads in microelectronic assemblies

Abstract A potentiostatic method was developed to investigate the ability of plasma-deposited silicon nitride thin films to protect microelectronic assemblies from corrosion due to aggressive contaminants. Test articles were immersed in 0.5 M NaCl at 0.0 V(SCE) and the resulting anodic current measured. The protective films reduced the corrosion current density by four orders of magnitude over the smooth, flat metallized Al regions representing bondpads, but by only one order of magnitude over the bondwires and by about 50% at the stitch bonds. These differences were due to the roughness of the bondwires and the occluded geometry of the bonds relative to the smooth metallized silicon areas.

Advanced decoupling in high performance IC packaging

This paper describes progress in the implementation of the Stealth/spl trade/ decoupling capacitor in high performance IC packaging applications. The Stealth is an integrable or surface-mountable capacitor with superior electrical performance characteristics compared with conventional surface mount devices. Simulations showing the effectiveness of the capacitor in reducing power distribution noise in IC packages are presented and a current application is discussed. Measurements on actual devices, demonstrating the sensitivity of decoupling effectiveness to intervening power distribution inductance, are shown. Finally, data on the reliability of the devices is presented. The use of the Stealth as part of a hierarchy of decoupling in the context of an advanced power distribution system is examined and ways of integrating the Stealth into a printed wiring board or BGA substrate are discussed. Also, a program under way to demonstrate this integration is described.