Crystal defects analysis using nano-probe technologies
With the device size shrinking to deep sub-micron region, silicon crystal defects become critical to device parameters. It also brings FA (Failure Analysis) great challenges on timely and exactly identifying the defect by EFA (Electrical Failure Analysis) and PFA (Physical Failure Analysis) methods. In this paper, we report the FA's on the single bit failure of a 6T-SRAM using nano-probe technologies for electrical localization. PFA methods, such as SEM (Scanning Electron Microscope), TEM (Transmission Electron Microscope), and chemical etching were performed for failure visualization.
Study on SRAM soft failure using planar-view transmission electron microscopy techniques
Soft failure in static random access memory (SRAM), where there are several mechanisms related to it, is a kind of major obstruction to improve the yield. Transmission electron microscopy (TEM) is a powerful failure analysis tool, which has a high spatial resolution and is widely used in IC failure analysis with the shrinkage of integrated circuit to a nano-level transistor. Planar-view TEM techniques have great advantages in finding failure location and mechanism. In this paper, two kinds of soft failure root causes are identified by the planar-view TEM techniques.
Application of FIB Circuit Edit and Electrical Characterization in Failure Analysis for Invisible Defect Issues
As semiconductor process technology rapidly develops into deep-sub-micron or nanometer regime, the feature size of semiconductor devices continues to shrink down. As a result, the defect being able to cause a device malfunction is also becoming smaller and smaller, and even certain defect is invisible with high-resolution SEM or TEM. It makes conventional physical failure analysis (PFA) face a great challenge for deep-sub-micron processed devices and the PFA success rate decrease because of such tiny or invisible defects. Thus electrical failure analysis (EFA) is becoming more and more important. FIB circuit edit and electrical characterization can provide critical clues of the failure mechanism through diagnosing the behaviour of a suspected defective transistor even if the defect is invisible with high-resolution SEM and TEM. This paper has demonstrated its application in failure analysis for two cases of invisible defect issues