Defect inspection challenges and solutions for ultra-thin SOI

This paper will explain the challenges and solutions for ultra thin SOI inspection using a laser light scattering based system. The impact of reflectivity on haze, sizing and minimum threshold will be detailed. We will show how the required sensitivity for 28nm (and beyond node) SOI inspection was achieved using a commercially available unpatterned DUV inspection system. We will also study improvements in defect classification.