Abstract A failure incurred in the front-end is typically a bottleneck to production due the need for physical failure analysis (PFA). Often the challenge is to perform timely localization of the front-end defect, or finding the exact physical defect for process improvement. Many process parameters affect the device behaviour and cause the front-end defect. Simply, the failures are of two types: high-resistance and leakage. A leakage mode defect is the most difficult to inspect. Although conductive atomic force microscopy and six probes nano-probing are popular tools for front-end failure inspection, some specific defects still need more effort. The electrical phenomenon and analysis of a crystalline defect will be demonstrated in this paper. The details will be discussed below.