Pushing Failure Mode Stimulus to Overcome the Limitation/Boundaries of Soft Defect Localization Tools

Temperature dependent failures are some of the most challenging cases that will be encountered by the analyst. Soft Defect Localization (SDL) is a technique used to analyze such temperature-dependent, ‘soft defect’ failures [1]. There are many literatures that discuss this technique and its different applications [2-7]. Dynamic Analysis by Laser Stimulation (DALS) is one of the known SDL implementations [8-11]. However, there are cases where the failure is occurring at a temperature where the laser alone is not sufficient to effectively induce a change of device behavior. In these situations, the analyst needs to think out of the box by understanding how the device will react to external conditions and to make necessary adjustments in DALS settings. This paper will discuss three cases that presents different challenges such as performing DALS analysis where the failing temperature is too high for the laser to induce a change of behavior from ambient temperature, cold temperature failure, complex triggering (Serial Peripheral Interface, SPI), and using an internal signal as input for DALS analysis. The approach used for a successful DALS analysis of each case will be discussed in detail.