Application of AFP (Atomic Force Probing) on the failure analysis of 65nm technology SRAM

Static random-access memory (SRAM) is a critical component across production and application. So the failure analysis for the SRAM is very important for the monitoring of the process. With the scale down of the technology, there come more challenges that the traditional method cannot deal with. In this paper, a real case of 65nm technology SRAM was studied. Nothing abnormal was found by the traditional FA method. A new method, current image-Atom Force Microscopy combined with Atom Force Probing, was employed. Abnormal current image contrast and abnormal family curve in the transistors of the SRAM cell was obtained easily According to the AFP result, the defect position was localized. TEM and EDX were performed on the localized position, and root cause was found.