Open critical area-constrained redundant via insertion

To improve via yield and reliability, redundant via insertion is a highly recommended technique proposed by foundries. However, inserting a redundant via can create extra open critical area between nets. A novel redundant via insertion method is proposed in this paper. In this work, we first address the problem of incremental open critical area for redundant via insertion, and then present an open critical area constrained redundant via insertion method. The experimental results show that under different extra open critical area constraint, the redundant via insertion rate declines in varying degrees. A large quantity of simulation data indicates that, when we choose 10% extra open critical area constraint, we can get a high insertion rate and have a good control of open critical area.