Test structure for fixing OPC of 200 nm pitch via chain using inner and outer dummy via array

A new test structure for fixing OPC (optical proximity correction) is proposed in which inner and outer dummy patterns surrounding an electrically connected 200 nm-pitch via chain array are used. An unconnected outer dummy via chain is designed as a protection dummy pattern for OPE (optical proximity effect) and flare caused by the exposure tool. An unconnected inner dummy via chain is designed to act as dummy array for failure analysis using the OBIRCH (optical beam induced resistance change) method. This test structure can be used for both electrical OPC evaluation and process failure analysis in the 65 nm-node wiring technology and beyond.