The Impact of TaS$_{2}$-Augmented Interconnects on Circuit Performance: A Temperature-Dependent Analysis

TL;DR

This paper presents a comprehensive temperature-dependent model for TaS$_{2}$-augmented copper interconnects, analyzing their circuit performance and identifying conditions for performance improvements over traditional interconnects.

Contribution

It introduces a detailed temperature-dependent modeling framework for Cu-TaS$_{2}$ interconnects and evaluates their circuit performance using RTL-GDSII flow at 7nm process node.

Findings

Cu-TaS$_{2}$ interconnects improve AES circuit clock frequency by up to 10.6%

Vertical resistivity of TaS$_{2}$ must be below 22 kΩ·nm for performance gains

The model captures surface and grain boundary scattering effects

Abstract

Monolayer TaS$_{2}$ is being explored as a future liner/barrier to circumvent the scalability issues of the state-of-the-art interconnects. However, its large vertical resistivity poses some concerns and mandates a comprehensive circuit analysis to understand the benefits and trade-offs of this technology. In this work, we present a detailed temperature-dependent modeling framework of TaS$_{2}$-augmented copper (Cu) interconnects and provide insights into their circuit implications. We build temperature-dependent 3D models for Cu-TaS$_{2}$ interconnect resistance capturing surface scattering and grain boundary scattering and integrate them in an RTL-GDSII design flow based on ASAP7 7nm process design kit. Using this framework, we perform synthesis and place-and-route (PnR) for advanced encryption standard (AES) circuit at different process and temperature corners and benchmark the circuit performance of Cu-TaS$_{2}$ interconnects against state-of-the-art interconnects. Our results show that Cu-TaS$_{2}$ interconnects yield an enhancement in the effective clock frequency of the AES circuit by 1%-10.6%. Considering the worst-case process-temperature corner, we further establish that the vertical resistivity of TaS$_{2}$ must be below 22 k${\Omega}$-nm to obtain performance benefits over conventional interconnects.