The sub-surface defects in annealed wafers with an oxide layer were characterized by ultraviolet-excited photoluminescence spectroscopy and mapping. Two types of defect were detected as a reduction of band-edge emission in the region determined to be defect-free by laser scattering tomography: an interface gap state between Si and the oxide layer, and a N-related defect (which was below the detection limit of laser scattering tomography).

Photoluminescence Characterization of Nano-Size Defects in Sub-Surface Region of Silicon Wafers. K.Tanahashi, H.Yamada-Kaneta: Surface and Interface Analysis, 2005, 37[2], 208-10