Finding the real root cause of electrically damaged devices is often challenging where it can mask out the real failure mechanism. The electrical damages might (might probably, one doubtful word is enough) be a consequence of the real failure mechanism. This paper aims to present cases and techniques to overcome the challenges of electrically damaged devices in identifying the real failure mechanism.

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.

Some of the most challenging task in analyzing fractures is a die that has not been fully cracked apart and a cracked die with electrical overstress damage. Traditional tools such as simple magnifying lens, optical microscope and up to the advance Scanning Electron Microscope are not enough to study the internal fractures or markings that could lead back to the origin of the crack. In order to study these internal fractures, the analyst tends to break the sample into pieces. However, this method creates additional mechanical stress and leads to a secondary crack where the point of origin will be difficult to analyze. This paper aims to introduce infrared microscopy in fractography (mainly on silicon) using cases and techniques to minimize the occurrence of secondary crack in analyzing internal fractures.