Photoluminescence and photoreflectance scanning of silicon-on-insulator materials

Photoluminescence (PL) and photoreflectance (PR) intensity maps of silicon-on-insulator (SOI) wafers tend to reveal much more than bare silicon. They are often rich in features due to both reflectance variations arising from the optical properties of the multi-layer stack, and to electrical variations across the wafers. PL scanning of these materials reveals many qualitative features useful in tracking uniformity across the wafer and repeatability between wafers from different fabrication runs