Published online by Cambridge University Press: 15 February 2011
To inspect quality of the surface region (the depth < 0.5μm) of Si wafer, where devices are to be fabricated, a new measurement method named Optical Shallow Defect Analyzer (OSDA) is developed. This method is based on light scattering at two wavelengths having different penetration depths in silicon. The system measures the depth distribution and the size distribution of defects near the surface by comparing intensities of the two scattered lights. The depth resolution of 0.1 μm, the high measuring throughput (total 6“Φ surface area/1hr) and the minimum detectable defect size of 20 nm are achieved. The OSDA is a powerful measurement system for nondestructive quality check of silicon wafers. We first present the data of epitaxial grown-in defects in μm order thickness epitaxial layers about the defect densities, the size distribution and the depth distribution.