Materials Impact on SRAM Timing: An Ab Initio Study of Interconnects

In this work, we demonstrate our first-principles based methodology to include atomistic level simulations to evaluate the promise of different metals on the performance of MOL/BEOL interconnects. The specific metals that we focus on include Cu, Ru (both fcc and hcp), Co, Mo, and W where the conductivity of these metals, including the degradation from grain boundaries is extracted from ab initio simulations, is included in a parasitic field solver and subsequently used to extract the interconnect parasitics of standard cells. PPA is evaluated through simulations of an 128x128 SRAM memory array where we find significant improvement in the read and write delay of 20% and 40%, respectively when we replace M1 with Ru(fcc).