Method and Apparatus for Sample Analysis

Abstract

A method of sample analysis is offered which provides improved quantitative accuracy. This method starts with irradiating a sample with an electron beam. Characteristic X-rays emanating from the sample are detected. Plural data sets about intensities of characteristic X-rays corresponding to a specific element contained in the sample are obtained. The element is quantitatively analyzed based on the plural data sets. This method includes a step (S 20 ) for calculating quantitative values for the element for the plural data sets, respectively, about the characteristic X-ray intensities, a step (S 30 ) for calculating weights for the quantitative values, respectively, based on the plural data sets about the characteristic X-ray intensities, and a step (S 40 ) for calculating a weighted average of the quantitative values based on the weights.

Having thus described my invention with the detail and particularity required by the Patent Laws, what is desired protected by Letters Patent is set forth in the following claims. 
     
         1 . A method of sample analysis for analyzing a sample by irradiating the sample with an electron beam, detecting characteristic X-rays emanating from the sample, obtaining plural data sets about intensities of characteristic X-rays corresponding to a specific element contained in the sample, and providing a quantitative analysis of the sample based on the data sets about the characteristic X-ray intensities, said method comprising the steps of:
 calculating quantitative values for the element for the plural data sets, respectively, about the characteristic X-ray intensities;   calculating weights for the quantitative values, respectively, based on the plural data sets about the characteristic X-ray intensities; and   calculating a weighted average of the quantitative values based on the calculated weights.   
     
     
         2 . The method of sample analysis as set forth in  claim 1 , further comprising the steps of:
 preparing an electron probe microanalyzer equipped with a plurality of spectrometers; and   detecting characteristic X-rays emanating from the sample by the spectrometers so as to obtain said plural data sets about the characteristic X-ray intensities.   
     
     
         3 . The method of sample analysis as set forth in  claim 1 , wherein said weights are peak intensities of characteristic X-rays corresponding to the element. 
     
     
         4 . The method of sample analysis as set forth in  claim 1 , wherein each of said weights is a ratio of a peak intensity of the characteristic X-rays corresponding to the element to a background intensity. 
     
     
         5 . A sample analyzer for irradiating a sample with an electron beam, detecting characteristic X-rays emanating from the sample, obtaining plural data sets about intensities of characteristic X-ray corresponding to a specific element contained in the sample, and providing a quantitative analysis of the element based on the plural data sets about the characteristic X-ray intensities, said sample analyzer comprising:
 a quantitative value calculator for calculating quantitative values for the element for the plural data sets, respectively, about the characteristic X-ray intensities;   a weight calculator for calculating weights for the quantitative values, respectively, based on the plural data sets about the characteristic X-ray intensities; and   a weighted average calculator for calculating a weighted average of the quantitative values based on the calculated weights.   
     
     
         6 . The sample analyzer as set forth in  claim 5 , wherein there is provided a plurality of spectrometers via which said plural data sets about the characteristic X-ray intensities are obtained. 
     
     
         7 . The sample analyzer as set forth in  claim 5 , wherein said weights are peak intensities of the characteristic X-rays corresponding to the element. 
     
     
         8 . The sample analyzer as set forth in  claim 5 , wherein each of said weights is a ratio of a peak intensity of the characteristic X-rays corresponding to the element to a background intensity.