This paper analyzes the limitations of the existing interconnect technologies and design methodologies and presents a novel three-dimensional (3-D) chip design strategy that exploits the vertical dimension to alleviate the interconnect related problems and to facilitate heterogeneous integration of technologies to realize a system-on-a-chip (SoC) design. A comprehensive analytical treatment of these 3-D ICs has been presented and it has been shown that by simply dividing a planar chip into separate blocks, each occupying a separate physical level interconnected by short and vertical interlayer interconnects (VILICs), significant improvement in performance and reduction in wire-limited chip area can be achieved, without the aid of any other circuit or design innovations. A scheme to optimize the interconnect distribution among different interconnect tiers is presented and the effect of transferring the repeaters to upper Si layers has been quantified in this analysis for a two-layer 3-D

The era of low power microelectronics began with the invention of the transistor in the late 1940 's and came of age with the invention of the integrated circuit in the late 1950's. Historically, the most demanding applications of low power microelectronics have been battery operated products such as wrist watches, hearing aids, implantable cardiac pacemakers, pocket calculators, pagers, cellular telephones and prospectively the hand-held multi-media terminal. However, in the early 1990's low power microelectronics rapidly evolved from a substantial tributary to the mainstream of microelectronics. The principal reasons for this transformation were the increasing packing density of transistors and increasing clock frequencies of CMOS microchips pushing heat removal and power distribution to the forefront of the problems confronting the advance of microelectronics. The distinctive thesis of this discussion is that future opportunities

In this paper the fundamental electrical limits of MOSFETs are discussed and modeled to predict the scaling limits of digital bulk CMOS circuits. Limits discussed include subthreshold leakage, short channel effects (SCE), gate induced drain leakage (GIDL), gate tunneling current, time dependent dielectric breakdown (TDDB), and hot carrier effects (HCE). This paper predicts the scaling of bulk CMOS MOSFETs for high performance microprocessors to reach its limits at drawn lengths of approximately 0:08¯m. Trends in scaling interconnects are also discussed. The device limits presented are used to project the characteristics of future processor technologies and to find scaling factors for the SPICE level 3 model parameters. A SPICE device model which can be scaled to reflect a range of MOSFET technologies from drawn lengths of 0:5¯m to 0:1¯m is presented along with a scalable wire model. Key Words and Phrases: MOSFET, device scaling, interconnect scaling, subthreshold leakage, short channel...

This work presents a new and computationally efficient performance optimization technique for distributed RLC interconnects based on a rigorous delay computation scheme. The new optimization technique has been employed to analyze the impact of line inductance on the circuit behaviour and to illustrate the implications of technology scaling on wire inductance. It is shown that reduction in the driver capacitance and output resistance with scaling makes deep submicron (DSM) designs increasingly susceptible to inductance effects. Also, the impact of inductance variations on performance has been quantified. Additionally, the impact of the wire inductance on catastrophic logic failures and IC reliability issues have been analyzed.

Continuous scaling of VLSI circuits is reducing gate delays but rapidly increasing interconnect delays. Semiconductor Industry Association (SIA) roadmap predicts that, beyond the 130 nm technology node, performance improvement of advanced VLSI is likely to begin to saturate unless a paradigm shift from present IC architecture is introduced. This paper presents a comprehensive analytical treatment of ICs with multiple Si layers (3-D ICs). It is shown that significant improvement in performance (more than 145%) and reduction in wire-limited chip area can be achieved with 3-D ICs with vertical inter-layer interconnects (VILICs). This analysis is based on dividing a chip into separate blocks, each occupying a separate physical level. A scheme to optimize interconnect distribution among different interconnect tiers is presented and the effect of transferring the repeaters to upper Si layers has been quantified in this analysis. Furthermore, thermal analysis of ICs with two Si layers is pres...