| dc.description.abstract | The systematic error is hard to distinguish in small diesize wafer. In order to solve the problem, this paper analyze six kinds of symptomatic failure types among the nine kinds of systematic errors. Each of failure types have been cut into different shapes. The randomness and homogeneity test are used to enhance the detection resolution of systematic error after doing wafer partition. Then, we observe the resolution ratio in systematic error after doing partition.
After cutting into various shapes, we use the randomness and homogeneity test to test each wafer. In randomness test, the hypothesis test is used. If the alternative hypothesis is over-cluster, the null hypothesis is determined to use a one-tailed test. And, we will check whether B-Score is higher than the critical value 1.64 or not. If the alternative hypothesis is non-random, the null hypothesis is determined to use two-tailed tests. Then, check the absolute value of B-Score is higher than 1.96 or not. Finally, you can draw a gateway diagram and divide it into five blocks. In the homogeneity test, we choose the yield parameter to support us to analyze wafer. If the yield difference of wafer is higher than the threshold after doing partition, the wafer may have systematic error.
Different partition method is used to distinguish different failure types. For example, we change the radius of the donut partition wafer to detect the edge-ring failure type and the defect position. Then, the applications of randomness and homogeneity test is used for the wafer after doing partition. Finally, the results of the test are combined to enhance the systematic errors resolution, so as to improve the yield and reduce costs. | en_US |