Mbist Diagnosis Algorithm And Self-Repair

As the complexity of VLSI circuits increasing, testing cost is becoming the most significant factor in the overall IC manufacturing cost. The conventional Auto Test Equipments can not meet the demand of at-speed testing of the complex circuits. The proliferation of large, high capacity embedded memory on system-on-a-chip(SOC)microelectronic applications has created the need for built-in self-test(BIST) method. Embedded memories are relatively inaccessibile through a chip's pins, making internal testing effective. Embedded memories, like stand-alone memories, suffer from random physical defects created during fabrication. Such defects are expentive because they decrease the manufacturing yield. Because of this, we research the fault model, algorithm and structure, which are the key to those questions.This paper modifies the inhere test algorithm to put forward the new one which has better coverage and diagnoses---- MARCH_TB+.Through the experiment in Garfield4,which is worked over independently by National Engineering Research Center for ASIC System of Southeast University ,the results show that it makes it. Its coverages over AF, TF, SAF, DRF those main fault are 100%, and expect SAF(1)andTF( /1), it can diagnose all other fault mode, especially it resolves SAF(0)andTF( /0), CFst(1;0)L and CFst(1;0)H, CFst(0;1)LandCFst(0;1)H. Besause of the modification, test time has some increase, but it will meliorate the primary test circuit area and full test time.This dissertation is organized as follows. First, the theoretical background to embedded memory's test and BIST is introduced. Then we bring forward the MARCH_TB+ algorithm on the basis of MARCH C- and test structure, afterward, we provide the experiment and conclusion. In the end, the 6th chapter is a summary of this paper and a prospect for future research.