| 摘要 |
PROBLEM TO BE SOLVED: To provide a contamination evaluation method that can evaluate even a minute amount of metal pollution introduced in a wafer with high sensitivity.SOLUTION: A cleaned silicon wafer is immersed in chemical liquid in which metal impurities are dissolved, and a defect (pit, projection) derived from metal pollution existing on the surface of the wafer are actualized (S3). Subsequently, the defect on the wafer surface is detected by a surface inspection device (S4), and SEM-EDX analysis is executed on the defect (S5, S6). The defect is classified in terms of defect seed on the basis of the analysis result (S7). The cross-sections of the defect is observed by TEM, and the depth or height of the defect is determined on the basis of an observation image of TEM. Subsequently, the volume of the defect is determined on the basis of the surface area of the defect determined from an SEM observation image and the depth or height of the defect determined from the TEM observation image (S9). The metal atom density in the defect is further determined. The metal pollution concentration in the wafer is calculated on the basis of the number of defects classified in terms of a predetermined defect seed and the volume and metal atom density of the defect (S11, S12). |
