A topology-based ECO routing methodology for mask cost minimization

Although several Engineering Change Order (ECO) routers had been proposed to obtain a routing solution based on different design objectives, mask re-spin cost still cannot be effectively reduced because the ECO routing problem is handled in a sequential manner. This paper presents a three-stage ECO routing flow which can simultaneously route all ECO nets while considering routing layer minimization. Experimental results demonstrate that our proposed ECO routing flow can effectively reduce the number of changed masks with only negligible wirelength and via overhead.