Accurate prediction of interconnect capacitance in Self-Aligned Quadruple Patterning

This paper proposes a simple yet sufficient interconnect modeling for parasitic capacitance extraction in a Self-Aligned Quadruple Patterning (SAQP) process. The proposed modeling expresses capacitance deviation as uniform sizing to interconnect edges. This model makes the SAQP more attractive compared to the Litho-Etch-Litho-Etch-Litho-Etch (LELELE) type of triple patterning, which includes variability due to mask misalign in principle. We experimentally prove the accuracy using FDM (Finite Difference Method) based simulations of electromagnetic fields. We also show a method to determine the amount of sizing.