Electrical simulation on the localized NVM failed cell by AFP nanoproing

As semiconductor technology advance, NVM memory structure find more and more application in the IC product. Majority part of NVM is charge-based where charge can be injected into or removed from a critical region of a device. This storage cell is normally floating and cannot be accessed directly. So the analysis on this floating structure is quite challenge, especially on the specific cell of the prime die. In this paper, a kind of NVM structure, OTP, was analyzed by the AFP nanoprobing. Combined with layout physical structure analysis an d electrical simulation on the failed cell by AFP, the failure mechanism was built up. Based on the electrical and circuit analysis, physical analysis, TEM cut, on the specific location was performed. Physical defect was observed, and the electrical analysis was proven.