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In this paper a method for analysis and modelling of transmission interconnect lines with zero or nonzero thickness on Si–SiO₂ substrate is presented. The analysis is based on semi‐analytical expressions for the frequency‐dependent transmission line admittances. The electromagnetic concept of free charge density is applied. It allows us to obtain integral equations between electric scalar potential and charge density distributions. These equations are solved by the Galerkin procedure of the method of moments. This new model represents narrow and thick line interconnect behaviour over a wide range of frequencies up to 20 GHz. The accuracy of the developed method in this work is validated by comparing with the rigorous simulation data obtained by full‐wave electromagnetic solver and CAD‐oriented equivalent‐circuit modelling approach. The response of the proposed model is shown to be in good agreement with the frequency‐dependent capacitance and conductance characteristics of general coupled multiconductor on‐chip interconnects.

New analytical approximation for the frequency‐dependent impedance matrix components of symmetric VLSI interconnect on lossy silicon substrate are derived. The results have been obtained by using an approximate quasi‐magnetostatic analysis of symmetric coupled microstrip on‐chip interconnects on silicon. We assume that the magnetostatic field meets the boundary conditions of a single isolated infinite line; therefore, the boundary conditions for the conductors in the structure are approximately satisfied. The derivation is based on the approximate solution of quasi‐magnetostatic equations in the structure (dielectric and silicon semi‐space), and takes into account the substrate skin‐effect. Comparisons with published data from circuit modeling or full‐wave numerical analyses are presented to validate the inductance and resistance expressions derived for symmetric coupled VLSI interconnects. The analytical characterization presented in this paper is well situated for inclusion into CAD codes in the design of RF and mixed‐signal integrated circuits on silicon.

Simple and accurate high frequency modelling approach of on‐chip interconnects on a lossy silicon substrate, that considers conductor and substrate skin effects, is presented. The closed‐form formulas for the frequency‐dependent series impedance parameters are obtained using a closed‐form integration method and the vector magnetic potential equation. The proposed frequency‐dependent inductance L(f) and resistance R(f) per unit length formulas are shown to be in good agreement with the electromagnetic solutions.

The purpose of this paper is to explore and evaluate the performance comparison of carbon nanotubes (CNT) and nickel silicide (NiSi) nanowires interconnects as prospective alternatives to copper wire interconnects.

The increasing resistivity of the copper wire with scaling and rising demands on current density drives the need for identifying new wiring solutions. This paper explores the various alternatives to copper. The metallic bundle CNTs and NiSi nanowires are promising candidates that can potentially address the challenges faced by copper. This paper analyzes various electrical models of carbon nanotube and recently introduced novel interconnect solution using NiSi nanowires.

The theoretical studies proves CNTs and NiSi nanowires to be better alternatives against copper on the ground of performance parameters, such as effective current density, delay and power consumption. NiSi nanowire provides highest propagation speed for short wire length, and copper is the best for intermediate wire length, while bundle CNTs is faster for long wire length. NiSi nanowire has lowest power consumption than copper and CNTs.

This paper investigates, assess and compares the performance of carbon nanotubes (CNT) and NiSi nanowires interconnects as prospective alternatives to copper wire interconnects in future VLSI chips.

Ultrafine feature sizes and high‐performance requirements have necessitated the integration of low‐k dielectrics with silicon‐level interconnects. These are mechanically weaker than previous‐generation materials, a fact that has been recognized to be an industry wide issue. The inherently weaker nature of the low‐k dielectric material can pose significant challenges to downstream electronic‐packaging processes and materials. The purpose of this paper is to focus on the wire bonding of gold wires on a Cu/low‐k pad structure.

The paper presents a numerical model description and simulation procedure.

Numerical methods, particularly finite element method based simulations are a good tool to visualize and understand the reasons for success or failure during a bonding process. It enables one to relate the induced stress to the inherent bulk material's strength and interfacial strength. The results from such simulations clearly indicate the high‐stress locations and the amount of plastic strain that accumulates during the application of compressive force, heat and ultrasonic energy.

These simulations help to understand the device's weaknesses and correlate the failures so as to design the wire bonder equipment with better process control features.

This paper attempts to review recent advances in wire bonding using insulated wire and new challenges in wire bonding for advanced microelectronics packaging.

Dozens of journal articles, conference articles and patents published or issued in 2004‐2007 are reviewed.

The advantages and problems/challenges related to wire bonding using insulated wire are briefly analysed, and several solutions to the problems and recent findings/developments related to wire bonding using insulated wire are discussed.

Because of page limitation of the paper, only brief review is conducted. Further reading is needed for more details.

This paper attempts to provide introduction to recent developments and the trends in wire bonding using insulated wire. With the references provided, readers may explore more deeply by reading the original articles and patent documents.

The goal of this review paper is to provide information on several commonly used thermography techniques in semiconductor and micro‐device industry and research today.

The temperature imaging or mapping techniques include thin coating methods such as liquid crystal thermography and fluorescence microthermography, contact mechanical methods such as scanning thermal microscopy, and optical techniques such as infrared microscopy and thermoreflectance. Their principles, characteristics and applications are discussed.

Thermal issues play an important part in optimizing the performance and reliability of high‐frequency and high‐packing density electronic circuits. To improve the performance and reliability of microelectronic devices and also to validate thermal models, accurate knowledge of local temperatures and thermal properties is required.

The paper provides readers, especially technical engineers in industry, a general knowledge of several commonly used thermography techniques in the semiconductor and micro‐device industries.

Information technology (IT) systems are already ubiquitous, and their future growth is expected to drive the global economy for the next several decades. However, energy consumption by these systems is growing rapidly, and their sustained growth requires curbing the energy consumption, and the associated heat removal requirements. Currently, 20-50 percent of the incoming electrical power is used to meet the cooling demands of IT facilities. Careful co-optimization of electrical power and thermal management is essential for reducing energy consumption requirements of IT equipment. Such modeling based co-optimization is complicated by the presence of several decades of spatial and temporal scales. The purpose of this paper is to review recent approaches for handling these challenges.

In this paper, the authors illustrate the challenges and possible modeling approaches by considering three examples. The multi-scale modeling of chip level transient heating using a combination of Progressive Zoom-in, and proper orthogonal decomposition (POD) is an effective approach for chip level electrical/thermal co-design for mitigation of reliability concerns, such as Joule heating driven electromigration. In the second example, the authors will illustrate the optimal microfluidic thermal management of hot spots, and large background heat fluxes associated with future high-performance microprocessors. In the third example, data center facility level energy usage reduction through a transient measurements based POD modeling framework will be illustrated.

Through modeling based electrical/thermal co-design, dramatic savings in energy usage for cooling are possible.

The multi-scale nature of the thermal modeling of IT systems is an important challenge. This paper reviews some of the approaches employed to meet this challenge.

Low power static‐random access memories (SRAM) has become a critical component in modern VLSI systems. In cells, the bit‐lines are the most power consuming components because of larger power dissipation in driving long bit‐line with large capacitance. The cache write consumes considerable large power due to full voltage swing on the bit‐line. The aim of the paper is to propose a new SRAM cell architecture to reduce the power consumption during write 0 and write 1 operation.

The proposed circuit includes two tail transistors in the pull‐down path of inv‐A and inv‐B. The simulated results of the proposed cell is compared with Conventional 6T SRAM cell and zero‐asymmetric SRAM cell.

The proposed SRAM cell consumes less power than the conventional SRAM cell during write operation. The write access delay is reported to be lower than conventional and ZA SRAMs in the proposed circuit. The read operation is similar to Conventional SRAM cell but due to tail transistors the read access delay and stability is poor in the present circuit which can be improved by careful transistors sizing.

The paper proposes a SRAM cell to reduce the power in write “0” as well as write “1”operation by introducing two tail transistors.