Computer Aided Design Software Development Of Electromigration Reliability Verification For On-chip Interconnects

Chip is ubiquitous in daily life,and it is at the core of medical equipment,spacecraft,weapons and other key equipment and systems.Therefore,the chip reliability has always been the focus of chip manufacturing,and it is largely limited by its reliability of on-chip integrated circuits.With the improvement of IC manufacturing technology,the feature size of IC has scaled down to nanoscale,which makes the reliability of IC face unprecedented challenges.Among the challenges,the problem of electromigration failure is one of the key factors restricting the reliability of IC.Considering the large scale and complex structure of the integrated circuit on the chip,because many Existing electromigration failure analysis algorithms can only work for a few specific wire structures in the circuit,these algorithms cannot analyze and obtain the electromigration reliability of the complete network.In addition,there are many methods that cannot balance the efficiency of operation with the accuracy of results,which need to be improved.In this paper,for the reliability analysis of electromigration on the large scale onchip integrated circuit,we propose a novel eigenfunction-based method for accurate transient analysis of the EM hydrostatic stress evolution.The proposed method could accommodate multi-segment metal interconnect structure,non-uniform thermal and current effects as well as arbitrary residual stress distribution.As multi-segment interconnect is the basic structure of IC,this method can be used to analyze arbitrary complex on-chip circuit structure.At the same time,in the process of solving partial differential equations,because this method does not require the,the proposed method is more efficient than the numerical solution method since it does not require any discretization either spatially or temporally.In the experimental part,by comparing with the results of existing simulation analysis methods,it is verified that this algorithm can not only guarantee the correctness,but also effectively improve the performance of the analysis.Based on the proposed transient stress analysis method,this paper develops an electromigration failure simulation system for the power grids where the phenomenon of electromigration is most prominent.It realizes the reliability analysis of electromigration for the on-chip power grids.The system can be used as an auxiliary tool to analyze the electromigration reliability of the IC in the chip design phase.The aided design system has important scientific significance and practical value for the reliability verification of the chip.