Interconnect performance and scaling strategy at 7 nm node

In this paper, optimization of 1X BEOL wiring level of 7 nm node is presented. We focus on the interconnect delay from 10 nm node to 7 nm node using a single stage driver circuit. The device delay is calculated based on the characteristics of the 10 nm driver circuit. Then the result is compared with a shrunk version of the circuit at the 7 nm dimension. Therefore, the impact of the BEOL on the circuit performance can be determined. The interconnect delay is plotted as a function of wire resistance, via resistance and capacitance. In order to better optimize the BEOL architecture, contour plots of resistance versus capacitance are presented in this paper. The result of this paper is indicating a strong dependency of circuit performance on the wiring length which is a new challenge. Optimization of BEOL architecture therefore requires a new approach which is outlined in this paper. As a result, we would like to bring this to the design community's attention.