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

Abstract—On-chip interconnect demand is becoming the dominant factor in modern processor performance and must be estimated early in the design process. This paper presents a set of heterogeneous architectural models that combines architecture description and Rent’s Rule-based wiring models. These architecture models allow flexible heterogeneous system specifications, enabling investigations of prospective designs in different technology scenarios. Comparisons against actual data demonstrate the models ’ effectiveness for architecture explorations with highly accurate estimations of local and global wiring demand, as well as chip area and cycle time. Simulation of two candidate system designs reveal trends in interconnect delay with increasing architectural complexity, and confirm the need for high computational locality and short global wires for future architectures. Index Terms—Architecture modeling, interconnect prediction, VLSI modeling, wire-demand prediction. I.

Over the years different interpretations of Rent's rule and different ways of estimating the Rent parameters have emerged. In general, these parameters are extracted from the average terminal-gate relationship for a set of circuit modules. We show that this relationship (the Rent characteristic) strongly depends on the definition of the circuit modules. These can be generated in many different ways, either from the topology of the circuit graph or, in a geometric way, by cutting regions from a circuit layout. The resulting Rent parameters can be quite far apart. This paper discusses the fundamental differences between the topological and the two geometric interpretations of the Rent characteristic that are expected to be most appropriate for current wirelength estimation techniques. Our discussion is based on experimental data, as well as on a theoretical model that can be used to estimate certain geometric Rent characteristics from the topological Rent parameters. Using this model, we derive a theoretical lower limit to the value of the average geometric Rent exponent. We also study the impact of the placement approach and placement quality on the geometric Rent characteristics.

Continuous scaling of VLSI circuits is reducing gate delays but rapidly increasing interconnect delays. Semiconductor industry 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. This analysis is based on dividing a chip into separate blocks, each occupying a 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. Various technologies being investigated for 3-D fabrication are reviewed. Finally, implications of 3-D architecture on several circuit designs are also discussed. 1 .

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...

this paper will address the limits that on-chip interconnects place on a GSI system design in the 21st century

Abstract not found

Vertical integration is a novel communications paradigm where interconnect design is a primary focus. By Vasilis F. Pavlidis, Student Member IEEE, and Eby G. Friedman, Fellow IEEE ABSTRACT | Design techniques for three-dimensional (3-D) ICs considerably lag the significant strides achieved in 3-D manufacturing technologies. Advanced design methodologies for two-dimensional circuits are not sufficient to manage the added complexity caused by the third dimension. Consequently, design methodologies that efficiently handle the added complexity and inherent heterogeneity of 3-D circuits are necessary. These 3-D design methodologies should support robust and reliable 3-D circuits while considering different forms of vertical integration, such as system-in-package and 3-D ICs with fine grain vertical interconnections. Global signaling issues, such as clock and power distribution networks, are further exacerbated