Feasibility study of fully self aligned vias for 5nm node BEOL

In this paper we present the concept of the Fully Self Aligned Via (FSAV) with motivation of achieving manufacturable litho process windows for patterning vias in 5nm-node interconnects. A process flow is proposed for FSAV which includes metal recess etching and insertion of an etch stop layer. Integration challenges for this flow are addressed and solutions demonstrated with complementary capacitance simulation.