Cracks on silicon die occur in a variety of patterns, because of varying amounts of force applied on die in varying directions. A common, non-destructive technique to detect cracked die is analysis with a Scanning Acoustic Microscope (SAM).[1] Although SAM is widely used to detect cracked die, empirical data infer that the technique does not quite detect several cases of crack that are observed by optical inspection after decapsulation of a package using chemicals - i.e., a destructive inspection technique. This study introduces a new, non-destructive inspection technique for die crack and crack pattern using a memory tester. The concept of the technique is based upon the fact that almost ninety percent of the space of a memory device consists of cell memories, thus if micro-crack is present, the phenomenon would cause malfunctioning of the memory- e.g., unable to be programmed, erased or read. By detecting and plotting - e.g., as a physical BITMAP-any electrical abnormalities in the memory cells, micro-crack pattern could be easily observed and studied.
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