A Novel Approach for Improving the Quality of Open Fault Diagnosis

With the shrinking process technologies and the use of copper process, open defects on interconnect wires, contacts and vias often cause failure. Development of an efficient fault diagnosis method for open faults is desired. However, the diagnosis method for open faults has not been established yet. In this paper, we propose a novel approach for improving the diagnostic quality of open faults by introducing a threshold function in which the logical value of the line with open defect depends on the weighted logical values of its adjacent lines. By using the threshold function, we can deduce not only a faulty line but also an open defect site at the faulty line. Experimental results show that the proposed method can identify an exact faulty line in most cases with a very small computation cost. The proposed method can also identify the open defect site within 25%-length of the faulty line.