A semiconductor substrate is exposed to an acid vapor, an impurity on the surface of the semiconductor substrate exposed to the acid vapor is scanned and collected with an acid solution, the acid solution after being subjected to the scanning and collecting is changed to a concentrated and dried object on a substrate having a mirror surface, the concentrated and dried object is changed to a particle-like concentrated object using an acid, and the particle-like concentrated object is analyzed using a total reflection X-ray fluorescence analysis device.