| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a standard sample from which the intensity of fluorescent X-rays can be measured by dropping a contaminated solution prepared by diluting a contaminant with a solvent having lower surface tension and a lower boiling point than water on the surface of the sample and drying the contaminated solution. SOLUTION: A contaminated solution 4 containing a metallic impurity of Ni is prepared by accurately diluting a standard solution for atomic absorption of an aimed element, for example, Ni with a solvent of high-purity isopropyl alcohol so that the concentration of the solution 4 may become a prescribed value. Then an amount of 100μl accurately collected from the contaminated solution 4 containing the metallic impurity 3 by means of a micropipet 5 and the collected solution 4 is dropped onto the hydrophilic surface 2 having natural oxide film of a silicon wafer 1 which becomes the basis of a standard sample. When the solution 4 is naturally dried, the solution 4 is dried in a moment due to the isopropyl alcohol having a low boiling point and the contaminant 3 is left on the surface 2 of the wafer 1, because the contaminant 3 is not able to follow the solution 4. Therefore, a contaminated area 6 in which the contaminant 3 is circularly spread is formed on the surface 2 of the wafer 1 in such a way that the area 6 is not concentrated to a narrow area after the solution 4 is completely dried.</p> |
