The application of pulse IV function in nano-prober system

A Nano-Prober System, combining scanning electron microscope (SEM), prober system, and measurement instrument is widely used in failure analysis field for soft localization. Most applications of the nano-prober system utilizes Direct Current (DC) electrical test to measure device characteristics. However, some failure mechanisms can hardly be diagnosed by applying traditional DC measurement. In this paper, Alternating Current (AC) pulse IV functional measurement was applied in soft failure study. A case screened out from speed test is adopted in this study. After non-abnormal is diagnosed via DC measurement, pulse IV measurement is used to conduct further measurement. While using pulse IV measurement method, the rising time of defective die is significantly longer than normal die, which is a convincing evidence that die failure is strongly related timing issue. Further Physical Failure Analysis (PFA) demonstrates that the poor connection between Poly and Contact layer is the major cause of the failure. The result of this paper indicates the effectiveness of pulse IV measurement in failure analysis.