In this work, we propose an analysis framework for em lifetime of pg tsv arrays. Tsv power supply array electromigration lifetime analysis in. Electromigration em in onchip metal interconnects is a critical reliability failure mech. Electromigration, electromigration in vlsi, signal integrity, hillocks in vlsi, void in vlsi, opens and shorts in vlsi, current density in vlsi. In boolean algebra, the true state is denoted by the number one, referred as logic one or logic high. Electromigration characteristics of al and alcu submicron lines, two level alcu lines with w studs, al fine lines under pulsed current stressing at high frequencies, and al and alcu fine lines under temperature cycling have been systematically studied. Methodology for electromigration signoff in the presence of. Em is the unenviable conclusion which leads to failures when current passes through the wires 1. In this paper, we propose a static electromigration analysis approach. Electromigration em in metal wires is a serious reliability problem.
Electric is a vlsi program that creates circuits that has the information of both the. Ansys redhawk training is a 8 weeks training program targeted for standard power noise and reliability signoff solution for soc designs. Static electromigration analysis for onchip signal. Rex a vlsi parasitic extraction tool for electromigration and signal analysis jerry p. In comparison to bjt, mosfets can be made very compact as they occupy very small silicon area on ic chip and also in term of manufacturing they are relatively simple.
Power and signal line electromigration design and reliability validation challenges for the 28nmera. Arzt, and nix, 1991 electromigration causes several different kinds of failure in narrow interconnect. Pdf this report describes the work accomplished during the period jan 89 to jan 90 on reliability analysis of vlsi cmos circuits for electromigration. Methodology for electromigration signoff in the presence. Black developed an empirical model to estimate the mttf of a wire segment, taking electromigration into consideration 3. Icpackage codesign of heterogeneous integrated systems xuejun fan. The effect is important in applications where high direct current densities are used, such as in microelectronics and related structures.
It occurs when the current density is high enough to cause the drift of metal ions in the direction of the electron flow, and is characterized by the ion flux density. Problems in developing reliable processors against em in increasing. Nearthreshold electromigration of damascene copper on tin. The temperature effect on electromigration reliability. Electromigration em is the gradual displacement of metal atoms in a semiconductor. Electromigration induced interconnect aging and its repercussions on the performance of nanometerscale vlsi circuits a dissertation submitted to the faculty of the graduate school of the university of minnesota by vivek mishra in partial fulfillment of the requirements for the degree of doctor of philosophy sachin s.
Electromigration em is a phenomenon of mass transport in metal film when the film is stressed with high electrical current density. Unique behavior or electromigration in solder joints 3. In service, an interconnect line carries an intense electric current. This includes metal widths, spacing, via definitions etc. Coupled analysis of electromigration reliability and. During normal circuit operation, the signal interconnects in a very large scale integration vlsi design are actually stressed with pulsed dc currents, rather that with continuous dc currents. Reason for electromigration is increase in current densities in net, which often occurs when strong cell drives thinner net in ctn clock tree network or in. Due to the small crosssectional area of the interconnections or thin films used in microelectronic devices, the current density at normal operating condition is extremely high and as a consequence the em induced mass transport. Icpackage codesign of heterogeneous integrated systems. If the current density is high enough, there can be a momentum transfer from moving electrons to the metal ions that make up the lattice of the interconnect material. The book provides a comprehensive overview of electromigration and its effects on the reliability of electronic circuits. Realistic electromigration lifetime projection of vlsi.
And in the digital electronic, the logic high is denoted by the presence of a voltage potential. Rex also performs network serial and parallel simplifications. The product should be reliable for the life time expected, but. Electromigration and its impact on physical design in. Electro migration in vlsi chips refers to the gradual degradation of interconnects. May 26, 20 electromigration mechanisms are accelerated by current density as well as temperature. Electromigration of flip chip solder joints snpb vs. Electromigration em is a critical problem for interconnect reliability in advanced vlsi design. Chapter 2 fundamentals of electromigration having shown in chap. Apr 11, 2018 electromigration is the gradual displacement of metal atoms in a semiconductor. It introduces the physical process of electromigration, which gives the reader the requisite understanding and knowledge for adopting appropriate counter measures.
Mitigating electromigration of power supply networks using. It covers electromigration, methodologies for electromigration aware design for analog and digital circuits, and methods for mitigating electromigration during the physical design, all in depth. While, the false state is represented by the number zero, called logic zero or logic low. As the structure size in electronics such as integrated circuits ics. Rarely, one can find a book with such scope and such practical applications. Methodology for electromigration signoff in the presence of adaptive voltage scaling weiting jonas chant, andrew b. As it can be noted from the roadmap, after 2024 there is no headroom for 2d geometry scaling where 3d vlsi integration of circuits and systems using sequentialstacked integration approaches. The process, known as electromigration, has been the most menacing and persistent threat to interconnect reliability. Because em is a strong function of current density, a smaller crosssectional area of interconnects can degrade the emrelated lifetime of ic, which is expected to become more severe in future technology nodes. Hwang digital equipment corporation 77 reed road hudson ma 01749 abstract rex is a program that extracts parasitic resistance and capacitance values for nodes in vlsi layouts. Tsv power supply array electromigration lifetime analysis.
Pdf electromigration analysis of vlsi circuits using the finite. Electromigration is an everincreasing problem as integrated circuits are pushed towards further miniaturization. Electromigration is the gradual displacement of metal atoms in a semiconductor. A floorplanning is the process of placing blocksmacros in the chipcore area, thereby determining the routing areas between them. Redhawk helps create highperformance socs which are power efficient and reliable for electromigration, thermal and electrostatic discharge issues. Electromigration what ic designers need to know industry. Cypress semiconductor mts 3 va vz 30% 70% dt input slew 30% 70% fall transition time. Ir drop analysis using redhawk overview vlsi basics. The device packing density in modern vlsi chips increases steadily. Pdf introduction to electromigrationaware physical design. Electromigration measurements of dualdamascene vlsi copper interconnect with sputtered tin barrier was performed to measure both longline jmax performance and em threshold jlmax. In this step, we create container which is known as design library. Electromigration em refers to the unwanted movement of materials in a semiconductor.
Redhawk is the signoff solution for all the foundries. Moreover, digital and memory ics can be employed with circuits that use only mosfets, i. Electromigration is a phenomenon, it can lead to opens and shorts due to metal ion displacement caused by the flow of electrons in metal, which can lead to functional failure of ic device. Ir drop voltage transfer in metal a drop occurs due to resistance of metal this is known as ir drop. It occurs when the current density through the conductor is high enough to cause the drift of metal ions. We show that under conditions that are typically met by vlsi interconnects, the charge transfer through wire segments of a net can be calculated directly by solving a system of linear equations, thereby eliminating the need for time domain simulation. Fundamentals of electromigrationaware integrated circuit. Waferlevel stress of via chains with various segment lengths was combined with a statistical efficient experiment design to explore various conditions with. Electromigrationaware interconnect design acm digital library. There will be changes in the interconnect temperature due to power dissipation of neighbouring interconnects or transistors on the chip, self heating of interconnect due to current flow, poor thermal. Pdf addressing electromigration em during physical design has become crucial to ensure reliable integrated circuits. Electromigrationinduced interconnect aging and its repercussions on the performance of nanometerscale vlsi circuits a dissertation submitted to the faculty of the graduate school of the university of minnesota by vivek mishra in partial fulfillment of the requirements for the degree of doctor of philosophy sachin s.
Signal em excessive current density within interconnects which if not effectively mitigated causes electromigration em. Electromigrationinduced interconnect aging and its. Electromigration is generally considered to be the result of momentum transfer from the electrons, which move in the applied electric field, to the ions which make up the lattice of the interconnect material. Static electromigration analysis for signal interconnects. Reliability verification is an important aspect in the design and development of an integrated circuit to guarantee its continued functioning over years of production use.
Modern design rules necessarily push the limits for. Pdf electromigration is increasingly relevant to the physical design of electronic circuits. Electromigration is the transport of material caused by the gradual movement of the ions in a conductor due to the momentum transfer between conducting electrons and diffusing metal atoms. Electromigration in ulsi interconnects sciencedirect. The most familiar are void failures along the length of the line called internal.
The inputs which are required for physical design are loaded into this design library. Impact of impurities, liner, co cap and short length on electromigration in cu damascene lines, 2014 stress workshop, austin. Ir drop analysis using redhawk overview vlsi basics and. D, university of kentucky, adjunct professor, ece dept. Digital circuit wearout due to electromigration in semiconductor. Study, analysis and modeling of electromigration in srams. Electromigration and its impact on physical design in future.
They guarantee lifetime by ensuring that their algorithms always deliver current densities that are within the limits specified in technology files. Exploiting bus level and bit level inactivity for preventing. It is caused by excessive current density stress in the. Pdf electromigration and the structure of metallic. Electromigration is an important reliability issue in nanoscale vlsi circuit designs. This is a industry standard format that has the information related to pin description and boundaries of the block instances in the design. Issues and challenges nithin s k, gowrysankar shanmugam, sreeram chandrasekar texas instruments india email. Vlsi design 2 verylargescale integration vlsi is the process of creating an integrated circuit ic by combining thousands of transistors into a single chip.
Electromigration modeling and layout optimization for. The conduction electrons impact metal atoms, and motivate the atoms to diffuse in the direction of electron flow. However, it has been shown that, in the absence of. Electromigration in vlsi of thin film interconnects deepdyve. We give the gds, cdl and technology file of the memory instance as the input.
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