JPS60135849A - Qualitative analysis by electron probe microanalyzer - Google Patents

Abstract

PURPOSE:To elevate the detection accuracy and the reliability in the qualitative analysis of a trace of elements contained by a method wherein the intensity of characteristic X ray of a sample is measured to identify an element with the highest peak in a wavelength profile and then, judgement is made on the presence of peak in the intensity data of higher order rays obtained sequentially. CONSTITUTION:The highest peak PA1 in the wavelength profile of a characteristic X rays of a sample point analyzed with an EPMA1 is detected with a peak detector section 12 of a qualitative analyzer 2 to identify an element A. In this profile which indicates the intensity of the primary ray of the element A, the intensity data PA2-PA4 of higher order rays are calculated with an arithmetic processing section 14 from the ratio of intensity PA1 of the primary ray and the intensity data of the element A is subtracted from the waveform profile to determine the intensity data PB1-PB5 of identified elements B. This operation is repeated until no peak exists in the remaining profiles PC1-PC4. This prevents the overlapping of peaks in two elements to eliminate misrecognition of peak thereby improving the accuracy of the qualitative analysis free from the presence of a trace element.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention mainly relates to a method for qualitatively analyzing measurement data obtained by using an electron probe microanalyzer (KPMA).

(b) Prior Art Generally, when applying FiPMA to perform qualitative analysis of elements contained in a sample, the intensity of characteristic X-rays is measured to determine the wavelength profile. In this case, conventionally, even when a trace element is contained in a sample, it is not possible to clarify whether it is a higher-order line peak of another element that exhibits strong intensity or whether it is the original peak of the trace element. As a result, the reliability of qualitative analysis could be compromised due to incorrect judgment of peak recognition.

(c) Purpose The present invention aims to solve the conventional problems and improve the reliability of the analysis by making it possible to sufficiently qualitatively analyze even trace amounts of elements.

In order to achieve this purpose, the present invention applies an electron probe microanalyzer (KPMA) to measure the characteristic X-ray intensity of the sample to determine the wavelength profile, and calculates the maximum peak contained within this wavelength profile. The element is identified based on the wavelength, the intensity of the higher-order line is determined sequentially from the primary line intensity of the identified element, the intensity data of the identified element is subtracted from the wavelength profile, and the remaining peak is calculated based on the subtracted wavelength profile. The presence or absence of such elements is determined and the elements contained in the sample are sequentially analyzed.

(e) Examples Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block configuration diagram including a qualitative analysis device and FiPMA applied to carry out the present invention. Looking at the same figure, code 1 is F! , PMA, 2 is a qualitative analysis device, and 4 is an interface connecting EPMAl and the qualitative analysis device 2. This qualitative analysis device 2 includes a central control unit 6 that performs various control processes, a first storage unit that stores characteristic Xligj1 wavelength data files and various program data, and an EPM.
A second storage unit that temporarily stores characteristic X-ray intensity data measured by Ai and data processed by the central control unit 6, a peak detection unit 12 that detects the presence or absence of a peak included in the wavelength profile of the characteristic X-rays, and a characteristic It is comprised of a calculation processing section 14 that performs calculation processing such as subtraction of X-ray intensity data, and a display section 16 that displays the calculation results.

Next, a qualitative analysis method using this apparatus will be explained with reference to the flowchart of FIG.

First, perform point analysis on the sample to be analyzed using PMAI, measure the intensity of characteristic X-rays emitted from the sample by turning EPMA I's X-ray spectrometer, and send the obtained wavelength profile data to interface 4. The data is sent to the qualitative analysis device 2 via the host computer (step n,).

The wavelength profile data input to the central control unit 6 of the qualitative analysis device 2 is transferred to the peak detection unit 12. The peak detection unit 12 detects whether a peak exists in the obtained wavelength profile (step ILi). If the wavelength profile has a peak as shown in FIG. 3(a), the maximum peak (
Since FA□) in FIG. 3(a) indicates the primary line intensity of one element A, the central control unit 6 selects the element showing the peak P A1 based on the peak detection signal of the peak detection unit 12.
Identification is performed with reference to the characteristic X-ray wavelength data file stored in the storage unit 8 (step na). Subsequently, the central control unit 6 transfers the read intensity data for the identified element from the first storage unit 8 to the calculation processing unit $14.
is calculated from the X-ray intensity data PA2 to PA of higher-order lines higher than the two normal lines of the identified element A under this measurement condition from the intensity PA of the -normal line and the ratio. Then, the central control unit 6 transfers the identified element A calculated by the arithmetic processing unit 14 and the intensity data PA1 to PA4 indicated by the identified element A to the second storage unit 10 and stores it therein (step n). Furthermore, the central control unit 6 reads out the previously measured wavelength profile (FIG. 2(a)) and the intensity data pA□-PA4 of the identified light amateurs from the second storage unit 10, and reads them again. Since it is sent to the arithmetic processing unit 14, the arithmetic processing unit 14 calculates the intensity data of the identified light amateur from the previous wavelength profile P A, ~P
Subtract A4 (to step). Next, the central control unit 6 transfers the remaining wavelength profile data subtracted by the arithmetic processing unit 14 to the peak detection unit 12, so the peak detection unit 12 determines whether or not a peak exists (step n6). If the peak still exists as shown in FIG. 3 (1)), return to step ) and calculate js of the maximum peak within the measurement target section X (FIG. 3 (1)) in the same manner as described above.
, ) indicates the primary line intensity of one element B. Based on this, the central control unit 6 selects the element exhibiting the peak PB1 by referring to the characteristic X-ray wavelength data file stored in the first storage unit 8. identify Then, the arithmetic processing unit 14 calculates the intensity data PB1 to PB5 of the identified element B, stores it in memory, and further calculates the intensity data PB1 to PB5 of the identified element B from the already subtracted wavelength profile (FIG. 3(b)). P Subtract B5. Then, the remaining wavelength profile is shown in Figure 3 (C
)become that way. In this way, the operations from step - to step are repeated in sequence until there are no remaining peaks. The results of the completed processing are then displayed on the display 16. Therefore, even when there is a possibility that the peak of one element overlaps with the peak of another element, the peak is clarified for each element, so there will be no error in identifying the peak.

(F) Effects As described above, according to the present invention, the intensity data shown by each identified element is subtracted, so if there are trace amounts of elements present, this becomes clear and increases the reliability of qualitative analysis. Excellent effects such as improved performance can be obtained.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a block diagram of an apparatus applied to carry out the present invention, FIG. 2 is a flowchart for explaining the procedure of qualitative analysis, and FIG.
The figure is a diagram showing a wavelength profile. Applicant: Shimadzu Corporation Representative: Patent Attorney Kazuhide Okada Figure 1

Claims (1)

[Claims] il+ Electron Probe Micro Analyzer (K
PMA) is applied to measure the characteristic X-ray intensity of the sample to determine the wavelength profile, identify the element based on the maximum peak wavelength included in this wavelength profile, and sequentially identify the higher-order line intensity from the primary line intensity of the identified element. The intensity data of the identified element for which the intensity of the identified element was determined is obtained from the wavelength profile 7? 1. A qualitative analysis method using an electron probe microanalyzer, characterized in that elements contained in a sample are sequentially analyzed by subtracting the wavelength profile from I-L and determining the presence or absence of a residual peak with respect to the subtracted wavelength profile.