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Non-volatile memory is the most important memory device in IC chips. As a memory, embedded non-volatile memory (NVM) is a fundamental structure in many kinds of semiconductor devices. It is commonly used in the modern electrical appliance as a code or data memory. For different applications, there are different memory designs or IP, like ROM, OTP, Flash, MRAM, PCRAM etc. The physical mechanism of these NVMs are different, some are electron based, some are resistance based and fuse or anti-fused based. The experiment described in this paper is performed on an electron charge storage based NVM. That means a medium is employed to store electron charge to differentiate two statuses “0” and “1”. Floating Poly gate is this medium used as electron charge storage in this NVM. Since the storage medium is in floating condition, it cannot be accessed externally. The methods of performing direct analysis are limited for this kind of device, especially in the case of subtle defects or soft fail. As semiconductor devices scale, the defects become smaller and more subtle. Nanoprobing is usually the only way to find the defect location electrically before any further physical analysis. In this experiment, the single bit NVM fail was analyzed. Different PFA methods used during the analysis, failed to find the defect. Nanoprobing was employed to precisely isolate the defect. Key word: nanoprobing, NVM, subtle defect, Poly-crystalline, floating gate

Reliability tests, such as High-Temperature Operating Life (HTOL), Hot Carrier Injection (HCI), Time Dependent Dielectric Breakdown (TDDB), etc., is required for the lifetime prediction of an integrated circuit (IC) product. Transmission Electron Microscopy (TEM) analysis is required to provide insights to the defect mechanisms, induced in the scaled gate oxide, by the above reliability tests. In this paper, application of high resolution Nano-probing Electron Beam Absorbance Current (EBAC) to isolate the defective locations for TEM analysis was investigated. We have successfully demonstrated that TEM analysis after Nano-probing EBAC fault isolation is an effective technique to reveal the failure root cause of gate oxide breakdown after reliability stresses.