Nano-scale defect investigation by site-specific transmission electron microscopy and electron energy loss spectroscopy

For the yield enhancement of sub-micron devices, physical or chemical analysis of very small feature is strongly needed. Transmission Electron Microscopy is well capable of such tasks. This paper gives a few case studies, in which cross-sectional TEM is effectively used for failure analysis. Each of them deals with sub-micron defect, which was isolated by functional and/or electrical tests. The defects were prepared for TEM investigation by using Focused Ion Beam technique with sub-micron special accuracy. Case studies describe an inter-metal contact open, metal to metal short, and diffusion to substrate short, where unique mechanism of dislocation generation in silicon were observed. Practical applications of Electron Energy Loss Spectroscopy (EELS) are also described