Accurately Localizing In Integrated Circuit Failure Analysis

In the Failure Analysis Of Integrated Circuit,it is difficult to find hard defects with a single defect location technology of Functionally Failing Integrated Circuits.With the temperature or other conditions changing,soft defects may cause some changes of the integrated circuit functional test results.It is increased the difficulty of accurately positioning with soft defects.This paper details the main defect examples and their damage to the circuit.The main methods of positioning defects in the world now are listed.There are two main defect location methods,Optical Beam Induced Resistance Change(OBIRCH)and Photon Emission Microscopy(PEM).Based on a large number of experiments,this paper develop a process method of hard defect locking with advantages.This method can gradually reduce the research scope of the failed circuit in a short time,and finally determine the defect point.In this way,it is can be achieved the purpose of efficiently and accurately locking various hard defections.Research shows,with the single single defect location method,it is needs at least two weeks or more time to locate the hard defects.The success rate also reduced to 60%.However,the hard defect locating period can be shorted to 5 days with the procedure method developed in this paper.The success rate will increased to about 95%.As to the soft defect,it is not easy to locate with this method.There are some solutions: achieve dynamic synchronization of integrated circuit test module and OBIRCH laser scanning system dynamic synchronization method;Achieve digital normalization with integrated circuit test conclusions of simulate mixed signals;efficiently and accurately lock soft defects in analog mixed-signal circuits and digital circuits with the defect location method of OBIRCH.The following are the innovations in this paper:Focusing on the advantages of the PEM method and the OBIRCH method,summarizing the optimization process method related to hard defect location,it can quickly reduce the analysis scope of the failed circuit in a short time,and finally locate the defect point,so as to efficiently and accurately lock the hard defect.In facing soft defects in digital circuits,this paper develop the dynamic synchronization method to achieve the purpose of integrated circuit test module and OBIRCH dynamic synchronization.In this way,it can locate soft defects effectively and precisely with OBIRCH method.There are some solution for soft defects in analog signal circuits.First,the variations of various analog signal parameters will be unified and converted into digital test result indicators.Therefore it can be recognized by OBIRCH while meeting the needs of dynamic synchronization.Furthermore,the OBIRCH method is used to efficiently and accurately lock soft defects in the analog mixed signal circuit.