Particularly in advanced technology nodes, interconnects significantly affect the
power, performance, area and reliability of integrated circuits. Requirements of high
integration density, performance, complex patterning technology and cost implications
make it imperative to determine optimal back-end-of-line (BEOL) stack dimensions for
sub-22nm technology nodes. This thesis studies copper interconnect scaling strategies
for high-performance IC designs. It focuses on determining optimal dimensions of the
BEOL interconnect stack to achieve least possible delay while maintaining low power
consumption. Degrees of freedom of the optimization technique in this work are wire aspect ratio (AR) and wire line-space duty cycle (DC).1 Our study targets the interconnect
scaling strategy for 28nm through 7nm integrated device manufacturer (IDM) nodes,
which have a more rigorous scaling trend than what is seen in the pure-play foundry
“node” taxonomy. For example, the 14nm IDM node has a minimum Metal-1 pitch of
52nm [31], while the corresponding pitch for the pure-play foundry 14nm technology
node is 64nm [39]. The studies in this thesis also indicate the advantages of using a low
wire aspect ratio and a high line-space duty cycle for sub-22nm technology nodes.
1 We define AR by T/W = metal thickness / metal width, and DC using L/(L + S) = line-width /
pitch.