Redundant Via Insertion Based on SCA
Junping Wang, Runsen Xing, Dan Xu, Yong-Bang Su, Ruiping Feng, Rong Wei, Yaning Li, Teng-Wei Zhao · IEEE Transactions on Very Large Scale Integration (VLSI) Systems · 2015
The redundant via (RV) insertion is a widely used technique to enhance chip reliability. However, inserting an RV adjacent to a single via (SV) may create extra critical area (CA) between nets and worsen the circuit's yield. In this paper, we present a short CA (SCA)-constrained RV insertion method for yield optimization with a consideration of the SCA. First, we find the candidate ranges of the SVs, judge whether they can be inserted by RVs, and set the values of their corresponding direction marks and weight. Then, we update the direction marks and the weight of the candidate ranges. Finally, according to the direction marks and the weight of the candidate ranges, we determine the optimization sequence of the candidate ranges and complete the insertion of the RVs. The simulation results show that our method can get a high insertion rate and a good control of the incremental SCA between nets for yield.