Detection of Fast Diffusing Metal Impurities in Silicon by Haze Test and by Modulated Optical Reflectance: A Comparison

Si‐<100>‐ and ‐<111>‐wafers intentionally contaminated by Fe, Co, Cu, Ni, and Pd have been subjected to rapid thermal annealing at 1200°C for 30s and studied by modulated optical reflectance (MOR) and defect etching. It is shown that there is 1:1 correspondence between wafer regions of increased MOR‐signal and high etch pit density ("haze"). Therefore it is possible to detect metal impurity precipitates by MOR in much the same manner as the haze test, with the advantage that no defect etching is necessary and that the measurements can be carried out in a process line.