Abstract
This paper presents the use of Dynamic Laser Stimulation (DLS) and Time-Resolved DLS (TR-DLS) to provide fail site localization and complementary information on a failed embedded memory IC. In this study, an embedded dual port RAM within a 90nm IC that failed one of the Memory Built-In Self Tests (MBISTs) was investigated. This technique rapidly localized the failing area within the memory read/write circuitry. The TR-DLS provided maps for each operation of the MBIST pattern. With this information, the failure was clearly identified as a read operation failure. The TR-DLS technique also provided much refined site signature (down to just one net) within the sense amp of the Port B of the dual port RAM. This information provided very specific indication on how to improve the operation of that particular sense amp circuitry within the dual port RAM Memory.
