| 摘要 |
PROBLEM TO BE SOLVED: To provide an impurity analysis method of a semiconductor substrate, which is capable of analyzing impurities existing in a depth direction from a surface of a semiconductor substrate and of specifying in-plane positions of the impurities.SOLUTION: First, vapor of a mixture of hydrofluoric acid and nitric acid is generated (S11). A silicon substrate is placed in a reaction chamber, and the vapor of the mixture is introduced to the reaction chamber to etch (decompose) a surface layer part of the silicon substrate by the vapor of the mixture (S12). Supply of the vapor of the mixture to the reaction chamber is stopped, and only N2 gas is supplied to the reaction chamber. The surface (decomposed surface) of the silicon substrate after decomposition is blown with the N2 gas for a prescribed time to remove silicon reaction residues from reaction residues remaining on the decomposed surface (S13). Thereafter, impurities on the decomposed surface are measured by a total reflection fluorescent X-ray analysis method (S14). In addition, a distribution in a depth direction of impurities can be evaluated by repeating the steps S12 to S14. |
