Statistical SDFC: A metric for evaluating test quality of small delay faults

As the technology node continues to shrink, an effective and accurate metric is essential to measure the test quality of small delay faults (SDFs), which may cause failure at circuit outputs. Owing to including gross delay fault (GDF) coverage, prior metrics cannot concentrate on the detection of SDFs. We propose a new metric, statistical SDF Coverage (S-SDFC), for differentiating SDFs and GDFs and evaluating the test quality of SDFs under the statistical delay quality model. Experimental results show that S-SDFC is more conservative and effective in evaluating the quality of test sets in detecting SDFs and outperforms other metrics in guiding test generation.