Resolution and sensitivity enhancements of scanning optical microscopy techniques for integrated circuit failure analysis

Scanning optical microscopy techniques are effective for optical fault localization of failures that are sensitive to thermal stimulation. In this paper, the recent developments in resolution and sensitivity enhancements that allow these techniques to be used with advanced technology nodes are described. The enhancement methods include refractive solid immersion lens technology, dc-coupling of the laser induced detection system and laser pulsing with signal integration algorithm. The combination of these enhanced scanning optical microscopy techniques and refractive solid immersion lens technology has brought about significantly better localization precision and sensitivity.