JP2000199749A - Fluorescence x-ray spectrometer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a fluorescence X-ray spectrometer easy in analytical operation and enabling quantitative analysis, even if the discrimination number of a sample is not definite. SOLUTION: Since a series of operations, wherein a sample S fed to an analyzing position by a start command is irradiated with X-rays and the intensity of fluorescent X-rays generated from the sample S is measured and a group to which the sample S belongs, is selected to quantitatively analyze the sample S are executed, analytical operation can be executed easily. Even if the discrimination number of the sample S is unclear, the quantitative analysis of the sample S becomes possible. Since a group, to which the sample S belongs is selected from a qualitative or semi-quantitative analytical result based on a first measured result, even if there are fluctuations in the measured value of the intensity of fluorescent X-rays, the errors in judgment of the sample S can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray fluorescence analyzer for measuring the intensity of fluorescent X-rays generated from a sample irradiated with X-rays and quantitatively analyzing the sample.

[0002]

2. Description of the Related Art Conventionally, as an apparatus for quantitatively analyzing a sample, an X-ray fluorescence analyzer for measuring the intensity of X-ray fluorescence generated from a sample irradiated with X-rays is known. This apparatus includes an X-ray source that irradiates a sample with X-rays, a spectroscope that separates the fluorescent X-rays generated from the sample, a detector that detects the separated fluorescent X-rays, and an electrical device that converts the detected fluorescent X-rays. A signal processing circuit for performing signal processing, and a controller (computer) for controlling the entire apparatus.

[0003] During quantitative analysis of a sample by this X-ray fluorescence spectrometer, an operator inputs an identification number (ID number) indicating the type of the sample into a computer, and a peak of an element to be measured of the sample, for example, iron (Fe). Measure strength. From the measured peak intensity, a group to which the sample belongs, such as iron ore or cement, is selected. The worker
According to this group, set measurement conditions such as the measurement time of the element to be measured, measure the fluorescent X-ray intensity of the sample under these measurement conditions, and perform quantitative analysis using the calibration curve method or the fundamental parameter method. Do.

[0004] Each of the above-mentioned work contents is displayed on a display screen of a computer, and an operator performs each operation while watching the display screen.

[0005]

However, in the conventional apparatus, an operator inputs a sample ID number, performs a computer operation for each operation, and performs data transmission and the like, so that the operation is complicated. There was a problem. Also,
Mistakes in inputting the ID number of the sample are also likely to occur. Furthermore, if the ID number of the sample is unknown, there is a problem that the measurement cannot be performed.

An object of the present invention is to solve the above-mentioned problems and to provide an X-ray fluorescence spectrometer capable of performing an analysis operation easily and performing a quantitative analysis even if the identification number of the sample is unknown. I have.

[0007]

In order to achieve the above object, the invention of claim 1 irradiates a sample with X-rays, measures the intensity of fluorescent X-rays generated from the sample, and quantitatively analyzes the sample. A fluorescent X-ray analyzer that emits fluorescence from a sample based on a start command to start the series of operations.
A group to which a sample belongs is selected from first measurement control means for measuring the intensity of the line, and a qualitative analysis result or a semi-quantitative analysis result based on the first measurement result obtained by the operation of the first measurement control means. Group selection means for performing measurement, second measurement control means for setting measurement conditions including the element to be measured in accordance with the group, and measuring the fluorescent X-ray intensity under the set measurement conditions, and the second measurement control Quantitative analysis means for obtaining a quantitative analysis value of the sample from the second measurement result of the element to be measured obtained by the operation of the means. Here, the semi-quantitative analysis includes (1) quantitative analysis of only a small number of elements, (2) quantitative analysis using a calibration curve prepared from a small number (for example, two) of standard samples, and (3) qualitative analysis. Includes quantitative analysis using coarse data. Further, the results of the qualitative analysis and the semi-quantitative analysis may be combined.

According to the first aspect of the present invention, the sample conveyed to the analysis position is irradiated with X-rays by a start command, the intensity of fluorescent X-rays generated from the sample is measured, and a group to which the sample belongs is selected. Thus, a series of operations for quantitatively analyzing the sample are automatically performed, so that the analysis operation can be easily performed. Further, even if the identification number of the sample is unknown, quantitative analysis of the sample becomes possible. Furthermore, since the group to which the sample belongs is selected from the qualitative analysis result or semi-quantitative analysis result based on the first measurement result, erroneous determination of the sample can be reduced even if the measured value of the fluorescent X-ray intensity fluctuates.

According to a second aspect of the present invention, in the first aspect, an identifier which is provided on the sample holder for holding the sample and indicates in advance that the sample is for automatic analysis, and the identifier is detected, Identification means for transmitting the start command.

According to the second aspect of the present invention, a start command can be automatically transmitted by detecting the identification body provided on the sample holder.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a configuration diagram of an X-ray fluorescence analyzer according to one embodiment of the present invention. This apparatus is a multi-element simultaneous analysis type for simultaneously analyzing a plurality of elements contained in a sample S such as a bulk sample, and irradiates the sample S transported to the analysis position Q with X-rays to generate the sample S. A series of operations of measuring the intensity of the fluorescent X-rays to be performed and quantitatively analyzing the sample S are performed. When the sample S is a thin film formed on a substrate, the quantitative analysis value obtained is the attached amount or the thickness of the thin film when the sample S is a thin film formed on a substrate.

This apparatus comprises an X-ray irradiator 2 for irradiating a sample S with primary X-rays B1, and a fluorescent X-ray B2 generated from the sample S.
3, a detector 4 for detecting the separated fluorescent X-rays B3 from the spectrometer 3, and a detected fluorescent X-ray B3
And a signal processing circuit 7 for electrically processing the signal. That is, the present apparatus is a chromatic dispersion type X-ray detecting means 2,
3 and 4 are provided. A plurality of spectroscopes 3 are arranged around the sample S.

Further, in the present apparatus, the samples S are transported one by one to the analysis position Q by the sample turret 12 arranged in the sample inlet 11. The sample S is automatically exchanged between a sample storage unit (not shown) and the sample inlet 11 by a sample automatic changer (not shown). The automatic sample changer is, for example, a crane type, which holds the sample S in the sample storage unit, moves the sample S to the sample inlet 11, and releases the sample S.

The sample holder H for holding the sample S is provided with a discriminator 18 such as a black band indicating that the sample S is for automatic analysis. The identification means 16 such as an optical sensor is provided, for example, near the sample input port 11,
The identification body 18 is optically detected.

Further, the present apparatus is provided with a controller 20 for controlling the entire apparatus. The controller 20 incorporates first and second measurement control means 22 and 24, a group selection means 26, and a quantitative analysis means 28 in its CPU (computer), and additionally includes a start command means 25, each data and a calibration curve. Storage means (memory) M for storing formulas and the like
It has a display unit D for displaying each operation content and each data content on the screen, and a printing means P for printing out the display content of the screen.

The start command means 25 sends out a start command d for starting a series of operations upon detection of the identification body 18. Upon receiving the start command d, the sample S
Is transported to the analysis position Q. First measurement control means 22
Opens a shutter (not shown) of the X-ray irradiator 2 to irradiate the sample X with the primary X-rays B1 and controls the signal processing circuit 7 to count the output pulses from the detector 4. The intensity of the fluorescent X-ray B3 generated from the transported sample S is measured. The group selection unit 26 selects a group to which the sample S belongs from a qualitative analysis result or a semi-quantitative analysis result based on the first measurement result obtained by the operation of the first measurement control unit 22. The second measurement control means 24
The measurement conditions including the element to be measured are set according to the group, the signal processing circuit 7 is controlled, the output pulses from the detector 4 are counted under the set measurement conditions, and the fluorescent X-ray intensity B3 is measured. Let it. The quantitative analysis unit 28 obtains a quantitative analysis value of the sample S from the second measurement result of the measurement target element obtained by the operation of the second measurement control unit 24.

The operation of the X-ray fluorescence analyzer having the above configuration will be described with reference to the flowchart of FIG. In this embodiment, a one-touch mode operation in which a series of operations are performed by a one-touch operation, and a normal mode operation in which an operator performs each operation in accordance with the display on the screen of the display unit D of the controller 20 can be selected.

In FIG. 1, first, when the operator starts the apparatus, the screen of the display unit D changes to an automatic analysis screen (step S1), and a sample such as a bulk sample held in the sample holder H is operated by the automatic sample changer. S is placed in the sample inlet 11 from the sample storage unit, or the position where the sample S is placed on the sample turret 12 moves to the sample inlet 11 (step S2). In this example, the automatic sample changer takes out a predetermined number of samples S in the sample storage unit, for example, sequentially from the end in the sample storage unit without specifying an identification number (ID number) indicating the type of the sample S, and takes out the samples. Sample S into sample inlet 1
I'm going to put it in 1.

In the case of the sample S for the one-touch mode, the sample holder H for holding the sample S is provided with a discriminator 18 such as a black band in advance. The presence or absence of the identification body 18 is optically detected by the identification means 16 (step S).
3). If the identification body 18 is not detected, the sample S
Is performed in the normal mode operation (step S10). When the identification body 18 is detected, a start command d for starting a series of operations is transmitted from the start command means 25, and the one-touch mode operation is automatically started (step S).
4) The sample S is transported from the sample inlet 11 to the analysis position Q (step S5). In the present invention, unlike the related art, the ID number of the sample S is not input, and the sample S is transported and subjected to the fluorescent X-ray analysis without specifying the ID number of the sample S. Therefore, the ID number of the sample S may be unknown.

It is to be noted that a start button is provided on the automatic analysis screen of the display unit D or on the apparatus without providing the identification means 18 on the identification means 16 or the sample holder H, and manual input is performed by pressing this button by an operator. A start command d for causing the start command means 25 to start the above series of operations by P
May be transmitted. Further, the operation of the automatic sample changer may be started by pressing this button.

Next, the fluorescent X-ray analysis of the sample S transported to the analysis position Q is started, and the first measurement control means 22 simultaneously outputs the output pulses from each detector 4 in a short measurement time to a signal processing circuit. 7, the intensity of the fluorescent X-ray B3 generated from the transported sample S is measured (first measurement) (step S6). Based on the measured intensities, peak detection and identification analysis of the element to be measured are performed in a data processing unit (not shown).

Thereafter, the group selection means 26 uses a plurality of types of elements to be measured contained in the sample S obtained from the measurement spectrum, for example, the peak intensities of chromium (Cr), nickel (Ni), iron (Fe), and the like. Approximate values of these contents are determined, that is, by semi-quantitative analysis, the sample S belongs to a range of values, such as stainless steel, iron ore, cement, etc., from the specification range of each value stored in the memory M in advance. A group is selected (step S
7). In the case where there is a change in the measured value of the fluorescent X-ray intensity, erroneous determination of the sample S is likely to occur only with the peak intensity of the element to be measured. In this example, not only the peak intensity of the element to be measured but also the approximate value of the content is calculated. Based on the selection of the group based on this, it is possible to reduce erroneous determination of the sample S.

The semi-quantitative analysis is performed by calculating the content of each element contained in the sample based on the measured intensity of the fluorescent X-rays of each element generated from the sample and the theoretical matrix correction constant calculated in advance. This is to determine the approximate composition of the sample.

First, using the equation (1), the content w _k of the known element k in the standard sample, the measured intensity I _mk , the content w _j of the coexisting element _j , and the theoretical matrix correction constant α
_{From kj} , measured X-ray intensity I _pk generated from a pure substance of element k
Is estimated.

[0025]

(Equation 1)

The intensity I of the fluorescent X-ray B3 generated from the sample S
_mk is measured, and for each of the generated fluorescent X-rays B3, the content rate w _k of each contained element _k is calculated by substituting it into the matrix correction formula of the formula (1). Thus, the approximate composition of the sample S is obtained.

FIG. 3 shows an example of a semi-quantitative analysis result in which the approximate values of the respective contents of the plurality of elements to be measured contained in the sample S are obtained. A group selection condition as shown in FIG. 4 is stored in the memory M, and a group of the sample S is automatically selected based on the semi-quantitative analysis result based on the selection condition. In the approximate values of the contents of the plurality of elements Cr, Ni, and Fe in FIG. 3, the element Cr is 16.3 (mass%).
From FIG. 4, the group of stainless steel is selected as the group to which the sample S belongs. Note that semi-quantitative analysis may be performed on all elements contained in the sample S. Further, instead of semi-quantitative analysis, the type of element may be obtained by qualitative analysis, and a group may be selected.

When the sample S is a thin film formed on a substrate, semi-quantitative analysis for obtaining an approximate value of the attached amount or the thickness of the thin film is performed. The content w _k of the element k and the content w _j of the coexisting element j are replaced by the known amount of adhesion or the thickness of the element k and the amount of adhesion of the coexisting element j in the standard sample, respectively. , (1) are applied. The intensity I _mk of the fluorescent X-ray B3 generated from the sample S is measured, and the generated fluorescent X
For each line B3, (1)
By substituting into the equation, the attached amount or film thickness of each contained element k is calculated. Thus, the approximate adhesion amount or film thickness of the sample S is obtained. In the same manner as described above, the memory M stores selection conditions for the adhesion amount and the film thickness as shown in FIG. 5, and the group of the sample S is automatically selected based on the semi-quantitative analysis result based on the selection conditions. You.

When the variation in the measured value of the fluorescent X-ray intensity can be neglected, or when the grouping can be roughly determined, the group should be selected only by the type (peak intensity) of the element to be measured contained in the sample S. It may be.

The range of the element to be measured is limited in the plurality of fixed spectrometers 3 in which the element to be measured is fixed as described above. However, when the range of the element to be measured is not limited, the range is separately set. Alternatively, a scanning goniometer may be provided, and the goniometer may be scanned over a predetermined wide element range to obtain a spectrum.

Then, the second measurement control means 24 applies appropriate measurement conditions according to the selected group, for example, the power of the X-ray irradiator 2, the X-ray irradiation time, the pulse count time of the signal processing circuit 7 ( The measurement time) is read out from the memory M, the X-ray irradiator 2 and the signal processing circuit 7 are controlled, and the output pulses from the detector 4 are counted by the signal processing circuit 7 for each measurement target element simultaneously over each measurement time. Then, the peak intensity of each element to be measured is measured (second measurement) (step S8). Thereafter, the quantitative analysis unit 28 obtains a quantitative analysis value of the sample S from the second measurement result of the element to be measured obtained by the operation of the second measurement control unit 24. That is, from the measured peak intensities, the content of the sample S is determined using a calibration curve method or a fundamental parameter method using a calibration curve equation corresponding to the type of element contained in the sample S stored in the memory M in advance. A rate is determined (step S9). This quantitative analysis result is temporarily stored in the memory M, then displayed on the display means D, and printed out by the printing means P.

FIG. 6 shows an example in which the result of the semi-quantitative analysis is compared with the result of the quantitative analysis based on the result of the semi-quantitative analysis. In this example, a low alloy group is selected as the type of the sample S from semi-quantitative analysis values of Si and Mn, and quantitative analysis is performed under appropriate measurement conditions in the low alloy group. This enables accurate quantitative analysis of the sample S.

When the amount of the sample S attached to the thin film or the thickness of the thin film sample S is analyzed, the appropriate measurement conditions corresponding to the group selected by the semi-quantitative analysis are read out from the memory M and the respective measurement objects are measured. The peak intensity of the element is measured (second measurement), and a calibration curve method using a calibration curve formula corresponding to the type of the element contained in the sample S stored in the memory M in advance from each of the measured peak intensities. Alternatively, a thin film deposition amount or film thickness analysis is performed using a fundamental parameter method. In this case, the quantitative analysis values of the elements contained in the sample S described above may be obtained at the same time.

As described above, in the present invention, the computer operation of the operator is made almost unnecessary by only one-touch operation, so that the analysis operation can be easily performed, and the ID number of the sample S is unknown. This also enables accurate quantitative analysis of the sample S.

The result of the quantitative analysis is transmitted or stored as a file. Information such as a selected group and a standard name is added to the quantitative analysis result file as needed. Also, using this file, C (carbon) measured by another device such as a gas analyzer is used.
Data processing such as recalculation is also performed based on the manually input elements such as the above and the fluorescent X-ray intensity data stored in the memory M.

In this embodiment, one-touch mode operation and normal mode operation can be selected.
Only the one-touch mode operation may be performed. In this case, since all the samples S are analyzed in the one-touch mode, there is no need to provide the identification means 16 or the identification body 18 in the sample holder H.

In this embodiment, the sample S is moved to the analysis position Q by the automatic sample changer and the sample turret 12.
However, the sample S may be manually placed at the analysis position Q.

Although the present embodiment is applied to the multi-element simultaneous analysis type, it may be applied to a scanning X-ray analyzer.

[0039]

As described above, according to the present invention, the sample conveyed to the analysis position is irradiated with X-rays by the start command, the intensity of the fluorescent X-rays generated from the sample is measured, and the sample belongs. Since a series of operations of selecting a group and quantitatively analyzing the sample are performed, the analysis operation can be easily performed. Further, even if the identification number of the sample is unknown, quantitative analysis of the sample becomes possible. Furthermore, since the group to which the sample belongs is selected from the qualitative analysis result or semi-quantitative analysis result based on the first measurement result, erroneous determination of the sample can be reduced even if the measured value of the fluorescent X-ray intensity fluctuates.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a fluorescent X-ray analyzer according to one embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the above device.

FIG. 3 is a diagram showing an example of a semi-quantitative analysis result.

FIG. 4 is a diagram illustrating an example of a group selection condition.

FIG. 5 is a diagram showing an example of a group selection condition.

FIG. 6 is a diagram showing an example of a semi-quantitative analysis result and a quantitative analysis result.

[Explanation of symbols]

11 sample inlet, 16 identification means, 18 identification body, 2
2 ... first measurement control means, 24 ... second measurement control means,
26: group selection means, 28: quantitative analysis means, S: sample.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2G001 AA01 BA04 CA01 EA01 EA08 FA06 GA01 GA13 HA16 JA11 JA13 KA01 LA02 NA10 NA11 NA17 PA01 PA02 PA03 PA06 PA14 SA04 SA12 2G058 AA02 CA05 CB11 CF11 CF16 GA20 GC02 GC05 GD02 GD06 GE01 GE06

Claims (2)

[Claims] A fluorescent X-ray for irradiating a sample with X-rays, measuring the intensity of fluorescent X-rays generated from the sample, and quantitatively analyzing the sample.
A line analyzer, based on a start command to start the series of operations,
First measurement control means for measuring the intensity of the fluorescent X-ray generated from the sample, and a qualitative analysis result or a semi-quantitative analysis result based on the first measurement result obtained by the operation of the first measurement control means, Group selection means for selecting a group to which a sample belongs; second measurement control means for setting a measurement condition including an element to be measured according to the group and measuring the fluorescent X-ray intensity under the set measurement condition; A fluorescent X-ray analysis apparatus comprising: a quantitative analysis unit that obtains a quantitative analysis value of a sample from a second measurement result of the element to be measured obtained by the operation of the second measurement control unit. 2. The identification unit according to claim 1, wherein the identification unit is provided on a sample holder for holding the sample and indicates in advance that the sample is for automatic analysis, and the identification unit is detected and the start command is transmitted. X-ray fluorescence analysis apparatus comprising: an identification unit for performing X-ray fluorescence analysis.