Low voltage In-lens secondary electron imaging in device failure analysis

With the increasing importance in understanding surface structures and in obtaining high resolution images at very low accelerating voltages, the recent developments in most of the detection systems are geared towards the use of In-lens secondary electron imaging. The In-lens detector collects only secondary electrons generated from the upper range of the interaction volume allowing to reveal more detailed surface information and to emphasize material differences in specimens. In-lens secondary electron imaging is, therefore, used to reveal surface features, film contaminants, and slight material contrasts in specimens that are not seen by common SE imaging. This paper will demonstrate the detection principle along with specific case studies where In-lens SE imaging facilitated in the resolution of device failure mechanisms.