JP2006313132A - Sample analyzing method and x-ray analyzing system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To nondestructively analyze an element which exists in a sample and is in a specific chemical bond state, and further analyze its concentration distribution along the depth direction. <P>SOLUTION: The sample is irradiated with X rays, and an X-ray edge absorption spectrum of fluorescent X rays emitted from the sample is measured, and then the chemical bond state of the element existing in the sample is specified from the pre-edge peak which appears on the low-energy side of the absorption edge. Then, a content concentration of the element whose chemical bond state is specified, is obtained from the fluorescence intensity of the pre-edge peak. Preferably, the sample is irradiated with the X rays having the wavelength of the pre-edge peak at two or more different angles of incidence, and fluorescence intensities of the pre-edge peaks are measured at respective different angles of incidence. Then, a depth distribution of the element whose chemical bond state is specified, is obtained from the fluorescence intensities of the pre-edge peaks measured at the different angles of incidence. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sample analysis method and an X-ray analyzer for detecting a compound having a specific chemical bonding state present in a sample and measuring the distribution in the depth direction in a nondestructive manner.

  Conventionally, it has been difficult to detect a compound having a compound having a specific chemical bonding state (for example, bonding at a specific valence) in a sample. SIMS (secondary ion mass spectrometry) is known as a highly sensitive sample analysis method, but SIMS cannot determine the chemical bonding state even if the amount and depth distribution of a single element can be evaluated.

  In contrast, in XPS (photoelectron spectroscopy), the energy of the detected photoelectrons slightly changes depending on the chemical bond, but the separation is difficult due to the energy resolution of the detector. Therefore, a method has been proposed in which the sample thin film is sandwiched between high-density films and the X-ray intensity in the film is increased using multiple reflection to facilitate detection (see, for example, Patent Document 1). This method can evaluate the concentration of trace elements in the thin film and the chemical bonding state.

  However, since photoelectrons are emitted only from the surface of the sample, when the film thickness to be evaluated is large and the element concentration and chemical bonding state change in the depth direction, the distribution in the depth direction cannot be evaluated.

On the other hand, in chemical analysis methods, a specific element is extracted by elution method, and its concentration is quantified with a chemical solution, but the elution ratio may vary depending on the sample or the chemical binding state may change depending on the elution treatment itself. .
JP 2000-55841 A

  Thus, the conventional analysis method has a problem that the chemical bonding state cannot be determined by SIMS, and the depth distribution cannot be evaluated by XPS.

  In addition, in chemical analysis methods such as elution methods, there is a high possibility of changing the chemical bonding state itself.

  Therefore, an object of the present invention is to provide a technique for identifying a chemical bond state of a compound present in a sample in a non-destructive manner and analyzing the amount and the distribution in the depth direction.

  It is another object of the present invention to provide a correction method that uses the content of a compound having a specific chemical bonding state determined nondestructively as a correction value for an analysis result obtained by a conventional chemical analysis method.

  It is another object of the present invention to provide an X-ray analyzer that analyzes the content and depth distribution of a compound having a specific chemical bonding state.

  In order to solve the above-mentioned problem, by irradiating a sample with X-rays and measuring the X-ray absorption edge spectrum of the generated fluorescent X-rays, a pre-edge peak peculiar to the chemical bonding state appearing near the absorption edge is used. The chemical bonding state (valence, etc.) of the elements present in the sample is specified.

  Here, fluorescent X-rays are used instead of the photoelectron yield method and the sample current method because the fluorescent X-rays generated in the sample have a larger escape depth than the photoelectrons generated at the same time. This is because distribution measurement is possible.

  Based on the detected fluorescence intensity, the concentration in the depth direction of the compound having a specific chemical binding state is analyzed.

  Further, the analysis result by the fluorescent X-ray is used as a correction value to correct the analysis result by the conventional chemical analysis method.

In a first aspect of the present invention, a sample analysis method is provided. The sample analysis method is
(A) irradiating the sample with X-rays;
(B) measuring an X-ray absorption edge spectrum of fluorescent X-rays generated from the sample, and identifying a chemical bonding state of an element present in the sample from a pre-edge peak appearing on a low energy side of the absorption edge; ,
(C) obtaining the concentration of the element whose chemical bonding state is specified from the fluorescence intensity of the pre-edge peak;
including.

In a preferred embodiment,
(D) irradiating the sample with two or more different incident angles at the pre-edge peak wavelength; and
(E) measuring the fluorescence intensity of the pre-edge peak at each of the different incident angles;
(F) obtaining a depth distribution of the element having the specified chemical bonding state based on the fluorescence intensity of the pre-edge peak at the different incident angles;
Further included.

In a second aspect of the present invention, a sample analysis correction method is provided. This correction method is
(A) Measure the concentration of an element that has a specific chemical bonding state in a sample by chemical analysis,
(B) including a step of correcting the measured concentration based on the concentration contained in the fluorescent X-ray spectrum described above.

According to a third aspect of the present invention, there is provided an X-ray analyzer capable of analyzing the presence and concentration of an element having a specific chemical bonding state in a non-destructive manner. X-ray analyzer
(A) a light source for irradiating the sample with X-rays;
(B) a detector for measuring the intensity of fluorescent X-rays generated from the sample;
(C) extracting a pre-edge peak appearing on the low energy side of the absorption edge of the fluorescent X-ray from the measurement result, and specifying a chemical bonding state of an element present in the sample based on the pre-edge peak; From the fluorescence intensity of the pre-edge peak, an analysis unit that analyzes the content concentration of the element in which the chemical bonding state is specified;
Is provided.

  Detection of a compound having a specific chemical bonding state present in a sample and measurement of its depth distribution can be performed accurately in a non-destructive manner.

  Further, by using the content concentration calculated based on the fluorescent X-ray intensity, the result obtained by a simple destructive analysis method such as an elution method can be corrected, and an accurate analysis result can be derived.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the accompanying drawings.

  FIG. 1 is a schematic configuration diagram of an X-ray analyzer according to an embodiment of the present invention. The X-ray analyzer 1 includes a light source 11 that irradiates a sample 10 with emitted X-rays, a detector 13 that detects fluorescent X-rays generated in the sample 10, and a measurement result detected by the detector. An analysis unit 15 is provided that identifies a compound in a chemical bonding state present therein and analyzes its content and distribution in the depth direction.

  In the example of FIG. 1, the emitted X-rays are guided to the sample 10 through the ion chamber 12. The ion chamber 12 is used to monitor the intensity of incident X-rays on the sample 10 and normalize intensity variations due to time or the like. The detector 13 is, for example, an SDD (Silicon Drift Detector), and measures fluorescence emitted by absorbing irradiated X-rays.

  The incident angle φ of the X-ray to the sample 10 is adjusted by changing the relative angle of the sample 10 with respect to the X-ray by an incident angle adjusting mechanism (rotation mechanism or the like) (not shown).

In this embodiment, a black chromate film coated on an iron substrate for rust prevention is used as a sample. The chromate film contains hexavalent chromium (Cr ⁶⁺ ) and trivalent chromium (Cr ³⁺ ), and the base material contains zero-valent chromium (Cr ⁰⁺ ). The analysis is performed with the measurement symmetry.

  First, X-rays are irradiated to the sample 10 while changing the energy of incident X-rays in the vicinity of the chromium absorption edge, and fluorescent X-ray measurement is performed at the X-ray absorption edge of the chromate film. At this time, the fluorescent X-ray spectrum depending on the incident angle is acquired by changing the angle of the sample 10 with respect to the X-ray (that is, changing the incident angle φ to the sample 10).

  The fluorescent X-rays are used instead of the photoelectrons because the fluorescent X-rays generated in the sample 10 have a larger escape depth than the photoelectrons generated at the same time, so that it is possible to measure the distribution up to the deep position of the sample 10. is there.

  FIG. 2 is a graph of the fluorescent X-ray spectrum measured by the detector 13. X-ray fluorescence is measured at five angles of incidence angle φ of 0.1 °, 0.5 °, 1.0 °, 5.0 °, and 20.0 °. By changing the incident angle, the penetration depth of the X-ray into the sample 10 changes, and information on the depth direction of the sample 10 can be obtained. For example, when the incident angle is 0.1 °, only the vicinity of the surface of the film is measured, and when the incident angle is 20 °, the measurement is performed covering the deep region from the surface.

  In the graph, the peak indicated by the arrow B is the absorption edge of the chromate film. A peak (arrow A) appearing at 5.993 (keV) on the lower energy side than the absorption edge B is a pre-edge peak of hexavalent chromium. That is, it is understood that hexavalent chromium is present in the sample (chromate film) by detecting the pre-edge peak at this incident energy (wavelength). If divalent or tetravalent chromium is contained, a pre-edge peak is displayed at the corresponding energy position. Therefore, whether or not divalent or tetravalent chromium is present depending on the presence or absence of such a pre-edge peak. Can be judged. Trivalent chromium does not show a pre-edge peak.

In the region indicated by the arrow C, that is, 6.087 to 6.124 (keV), the incident angle dependency is not shown, and the intensity I ₁ of the fluorescent X-rays emitted from the chromate film is almost constant.

The analyzing unit 15 calculates I ₁ / I ₀ from such a fluorescent X-ray spectrum based on the intensity I ₁ of the fluorescent X-ray generated from the chromate film at each energy and the incident X-ray intensity I ₀ . Further, normalization is performed so that the average value of I ₁ / I ₀ becomes 1 in the region of 6.087 to 6.124 (keV) indicated by the arrow C. I ₁ / I ₀ in 6.087 to 6.124 (keV) is a substantially constant value, indicating information on the total amount of chromium constituting the chromate film.

  FIG. 3 is an enlarged view of the vicinity of the pre-edge peak at 5.993 (keV) in the graph of FIG. As described above, the pre-edge peak at 5.993 (keV) is a peak peculiar to hexavalent chromium. That the intensity of the pre-edge peak of hexavalent chromium varies depending on the X-ray incident angle means that there is a distribution of the content (concentration) of hexavalent chromium in the depth direction. In the example of FIG. 3, it can be seen that the intensity of the pre-edge peak at the incident angle of 1.0 ° is the strongest, and the average content of hexavalent chromium from the surface to the penetration depth at the incident angle is the largest.

Since the peak specific to hexavalent chromium is standardized by the total amount of chromium, the analysis unit 15 analyzes the intensity of this peak to determine the content ratio of hexavalent chromium (Cr ⁶⁺ ) to the total amount of chromium (Cr). calculate. For example, if the sample is composed of zero-valent chromium, trivalent chromium and hexavalent chromium, Cr = Cr ⁰⁺ + Cr ³⁺ + Cr ⁶⁺ . Calculate the ratio.

That is, the same measurement is performed for a standard sample whose content of hexavalent chromium is known to be 100%, and the ratio of hexavalent chromium to the total amount of chromium (Cr ⁶⁺ / Cr) is calculated using Equation (1). calculate.

ここで、Ｉ（標準試料）は６価クロムが１００％である酸化クロム（ＶＩ）の５．９９３（keV）におけるピークの積分強度、Ｉ（クロメート膜）は、クロメート膜の５．９９３（keV）におけるピークの積分強度を示す。

Here, I (standard sample) is the integrated intensity of the peak at 5.993 (keV) of chromium oxide (VI) in which hexavalent chromium is 100%, and I (chromate film) is 5.993 (keV) of the chromate film. ) Shows the integrated intensity of the peak.

FIG. 4 is a graph showing the calculation results of the hexavalent chromium content ratio (Cr ⁶⁺ / Cr) at each incident angle. The Cr ⁶⁺ / Cr ratios at incident angles of 0.1 °, 0.5 °, 1.0 °, 5.0 °, and 20.0 ° are 14.1%, 15.3%, and 25.9%, respectively. 15.9% and 11.8%. These content ratios are average information from the surface to the penetration depth at the corresponding incident angle. Thus, by measuring the fluorescence intensity of the peak appearing near the absorption edge at a plurality of different incident angles, the depth distribution of the compound in a specific chemical bonding state can be obtained.

  Next, depth distribution analysis according to the second embodiment will be described. Also in the second embodiment, a general chromate film is used as the sample 10.

FIG. 5 is a graph showing the results of measuring the dependence of the total amount of chromium and the incident angle of hexavalent chromium on the chromate film of the second embodiment. From the spectrum measurement result of the first embodiment, it is known that there is a hexavalent chromium peak at 5.993 (keV). Therefore, the X-ray analyzer 1
(1) 5.993 (keV): hexavalent chromium peak,
(2) 5.988 (keV): hexavalent chromium low energy side background,
(3) 5.997 (keV): Hexavalent chromium high energy side background,
(4) 6.120 (keV): total amount of chromium,
With the four incident energies, an incident angle scan is performed to measure the fluorescent X-rays by changing the incident angle.

  The analysis unit 15 calculates the intensity of hexavalent chromium by estimating the intensity of the background from the low energy background and the high energy background and subtracting the estimation result from the intensity of the hexavalent chromium peak. The calculated incident angle dependent intensity of hexavalent chromium is indicated by a triangular measurement point (line A) in the graph of FIG. On the other hand, as the strength of the total amount of chromium, the measured strength at 6.120 (keV) is used as it is. The incident angle dependent intensity of the total amount of chromium is indicated by a black circle measurement point (line B) in the graph.

Next, the analysis unit 15 equally divides the sample 10 in the film thickness direction (for example, 10 divisions). If the chromate film thickness is 1550 nm, it is divided into 10 layers of 155 nm. Then, the electric field strength in each layer is calculated from the density and surface roughness of each layer. For example, LG Parratt, “Surface Studies of Solids by Total Reflection of
X-rays ”, Physical Review Vol. 95, at 359 (1954).

If the refractive index in the _jth layer from the surface is n _j ,
n _j = 1−δ _j −iβ _j (2)
It is expressed as here,
_{δ j = N A (ρ j} / A j) r e λ 2 (f 0j + f 'j) / (2π)
_{β j = N A (ρ j} / A j) r e λ 2 (f "j) / (2π) (3)
In and, N _A is the density of Avogadro number, [rho _j is the j-th layer, A _j is the atomic weight, r _e is the classical electron radius, lambda is the wavelength of X-rays, f _0j Thomson scattering term, f _'j is anomalous dispersion The real part of the term, f ″ _j means the imaginary part of the anomalous dispersion term.

Also, the Fresnel coefficients for reflection r _j and transmission t _j at the interface between the j layer and the (j + 1) layer are respectively
r _j = (N _j −N _{j + 1} ) exp (−2N _j N _{j + 1} σ ² _j ) / (N _j + N _{j + 1} ) (4)
t _j = 2N _j exp ((N _j −N _{j + 1} ) ² σ ² _j ) / (N _j + N _{j + 1} ) (5)
It is represented by Here, N _j = (θ ² −2δ _j −2iβ _j ) ^1/2 , θ is the X-ray incident angle, and σ is roughness.

The transmitted electric field E ^t _j and the reflected electric field E ^r _j in the j layer are respectively
E ^t _{j + 1} = a _j E ^t _j t _j / (1 + a ² _{j + 1} X _{j + 1} r _j ) (6)
E ^r _j = a ² _j X _j E ^t _j (7)
It is. here,
a _j = exp (−2πid _j N _j / λ)
X _j = (r _j + a ² _{j + 1} X _{j + 1} ) / (1 + a ² _{j + 1} X _{j + 1} r _j ) (8)
In and, d _j denotes the thickness of the j layer.

From the above, the electric field E _j (Z) at the depth Z of the j layer is
E _j (Z) = E ^t _j exp (−2πiN _j Z / λ) + E ^r _j exp (2πiN _j Z / λ)
(9)
Thus, the electric field intensity | E _j (Z) | ² is calculated.

Since the fluorescence intensity is proportional to the electric field intensity and the concentration in the depth direction of the target hexavalent chromium, the hexavalent chromium depth concentration distribution C _j divided into 10 is added to the electric field intensity obtained as described above. By multiplying and integrating in the depth direction, the fluorescence intensity I _cal can be calculated.

I _cal ∝ΣC _j | E _j (Z) | ² (10)
Comparing the calculated fluorescence intensity I _cal with the measured fluorescence intensity I shown in FIG.
χ ² = Σ (I−I _cal ) ² (11)
And the depth concentration distribution C _j is determined so that the difference is minimized.

FIG. 6 is a depth concentration distribution of hexavalent chromium obtained as described above. The horizontal axis in FIG. 6 is the layer number from the surface side (that is, the depth from the surface), and the vertical axis is the content (%) of hexavalent chromium (Cr ₆₊ ) with respect to the total amount of chromium (Cr).

  The number of layers in which the film thickness of the sample 10 is divided can be appropriately set depending on the film thickness of the sample 10, the measurement efficiency of fluorescent X-rays, the target analysis accuracy, and the like.

  Next, a concentration calibration method according to the third embodiment will be described. In the third embodiment, an example in which the measurement result (concentration) of the chemical analysis method using the elution test method is calibrated using the concentration of hexavalent chromium obtained from the measurement result of fluorescent X-rays will be shown.

  FIG. 7 shows the result of comparing the hexavalent chromium content calculated from the fluorescent X-ray measurement and the hexavalent chromium elution amount calculated from the dissolution test. In the dissolution test, when a zinc film is present on the underlayer of the chromate film or when the chromate film is thick, it is difficult to elute, and how much hexavalent chromium is eluted out of the hexavalent chromium contained in the film. Not clear.

  Therefore, as shown in FIG. 7, by creating a calibration table based on the hexavalent chromium content calculated from the X-ray absorption edge measurement, the concentration calibration for chemical analysis can be performed. In FIG. 7, the dotted line indicates the content of hexavalent chromium obtained by fluorescent X-ray measurement, and the solid line indicates the correlation with the elution amount of hexavalent chromium measured by the elution method. The fact that the correlation does not become a straight line indicates a difference in elution efficiency depending on the thickness of the sample. That is, as the film thickness increases, elution efficiency decreases, and the actual concentration cannot be reflected. In the example of FIG. 7, from the surface to about the sixth layer, the fluorescent X-ray measurement and the measurement result by the elution method are almost the same, but the elution amount is insufficient in a deeper region.

  Since the elution method can easily measure the concentration of a compound in a specific chemical binding state without the need for a large-scale measuring device, it is based on the measurement result of the chemical elution method based on the fluorescent X-ray measurement result (reference content). By applying the correction, the content of a specific compound can be obtained accurately and simply.

  FIG. 8 is a schematic block diagram of the analysis unit 15 used in the X-ray analysis apparatus 1 of FIG. The result of fluorescent X-ray measurement by the detector (fluorescence intensity measurement unit) 13 such as SDD is input to the analysis unit 15. In the analysis unit 15, the pre-edge peak detection unit 21 detects a pre-edge peak that appears on the low energy side of the absorption edge from the X-ray absorption edge spectrum of fluorescent X-rays. The chemical bond state specifying unit 22 specifies the chemical bond state of an element (compound) present in the sample 10 from the detected pre-edge peak. The chemical bonding state may be specified by using a table or the like in which the absorption energy at the pre-edge peak is associated with various elements and chemical bonding states in advance.

  The depth concentration distribution calculation unit 23 obtains the concentration (content ratio) of the compound in the specified chemical bonding state from the fluorescence intensity of the pre-edge peak.

  The depth concentration distribution calculation unit 23 also calculates the sample 10 from the intensity of the fluorescent X-ray obtained as a result of the incident angle scan at the wavelength of the pre-edge peak, that is, the X-rays irradiated to the sample 10 at two or more different incident angles. The concentration distribution in the depth direction is calculated (first embodiment).

  From the measurement result of the X-ray absorption edge spectrum, the depth concentration distribution calculation unit 23 further calculates the fluorescence intensity at the pre-edge peak and the fluorescence intensity at an X-ray energy higher than the absorption edge (region C in FIG. 2). The concentration of the compound (element) in a specific chemical bonding state in the sample 10 is calculated from the intensity ratio.

  Furthermore, the thickness of the sample 10 is divided by a predetermined number, and the content ratio of the compound in a specific chemical bond state is calculated for each of the divided thicknesses, thereby obtaining a distribution in the depth direction (second embodiment). ).

  Such an operation of the analysis unit 15 may be realized by a software program. In that case, the software program detects a pre-edge peak appearing on the low energy side of the absorption edge from the X-ray absorption edge spectrum measured by the detector (fluorescence intensity measurement section) 13 in the analysis unit 15. And a procedure for analyzing the concentration of an element having a specific chemical bonding state present in the sample 10 from the intensity of the pre-edge peak.

  Furthermore, a specific chemical bonding state existing in the sample 10 is determined from the measured intensity of the fluorescent X-ray generated from the sample 10 irradiated with X-rays at two or more different incident angles at the pre-edge peak wavelength. The procedure for obtaining the depth distribution of the element is executed.

  Further, the fluorescence intensity at the pre-edge peak and the fluorescence intensity at the X-ray energy higher than the absorption edge (region C in FIG. 2) are extracted from the measurement result of the X-ray absorption edge spectrum to the analysis unit 15; From the intensity ratio, a procedure for calculating the concentration of the compound in a specific chemical bonding state in the sample 10 is executed.

  In addition, the analyzer 15 divides the film thickness of the sample 10 by a predetermined number, calculates the content ratio of the compound in a specific chemical bond state for each divided film thickness, and obtains the distribution in the depth direction. Let it run.

  As mentioned above, although this invention was demonstrated based on specific embodiment, this invention is not limited to these embodiment.

  In the embodiment, the measurement and analysis are performed using the chromate film, but the present invention may be applied to a chromium-containing sample other than the chromate film. The analysis target is not limited to chromium, and other transition elements such as vanadium and copper having a specific valence may be used.

  Further, although radiation light is used as the X-ray light source, a laboratory X-ray light source such as tungsten or molybdenum may be used.

  Further, in this measurement, the fluorescence is detected by the SDD, but other detectors such as an SSD (Solid State Detector) or a rifle detector may be used.

  In addition, when preparing a large number of X-ray incident energies corresponding to pre-edge peaks of a compound in various chemical bonding states and obtaining a concentration distribution of a specific compound, the incident energy of the pre-edge peak is used. If the incident angle scan is performed, the concentration distribution of a wide variety of compounds can be obtained efficiently.

Finally, the following notes are disclosed regarding the above description.
(Appendix 1) irradiating the sample with X-rays;
Measuring an X-ray absorption edge spectrum of fluorescent X-rays generated from the sample, and identifying a chemical bonding state of an element present in the sample from a pre-edge peak appearing on a low energy side of the absorption edge;
From the fluorescence intensity of the pre-edge peak, obtaining the content concentration of the element for which the chemical bonding state is specified;
A sample analysis method comprising:
(Supplementary Note 2) The method further includes a step of measuring the fluorescent X-ray intensity as a standard intensity when the content concentration of the element in which the chemical bonding state is specified is 100%,
The sample analysis method according to appendix 1, wherein the content concentration of the element whose chemical state is specified is obtained from a ratio between the fluorescence intensity of the pre-edge peak and the standard intensity.
(Supplementary Note 3) Irradiating the X-rays at two or more different incident angles to the sample at the wavelength of the pre-edge peak;
Measuring fluorescence intensity of pre-edge peaks at each of the different incident angles;
Obtaining a depth distribution of the element with the specified chemical bonding state based on the fluorescence intensity of the pre-edge peak at the different incident angles;
The sample distribution method according to supplementary note 1, further comprising:
(Supplementary Note 4) From the measurement result of the X-ray absorption edge spectrum, the fluorescence intensity at the pre-edge peak and the fluorescence intensity at an X-ray energy higher than the absorption edge are measured, and the chemical ratio is calculated from the intensity ratio. The sample analysis method according to claim 1, further comprising a step of calculating a content concentration of the element whose binding state is specified.
(Supplementary Note 5) A step of dividing the film thickness of the sample by a predetermined number, calculating a content ratio of the compound in which the chemical bonding state is specified for each divided film thickness, and obtaining a distribution in the depth direction. The sample analysis method according to supplementary note 1, further comprising:
(Appendix 6) By chemical analysis, measure the concentration of elements present in a sample with a specific chemical bonding state,
A sample analysis correction method, wherein the measured concentration is corrected based on the content concentration obtained by the method according to any one of appendices 1 to 5.
(Supplementary note 7) a light source for irradiating the sample with X-rays;
A detector for measuring the intensity of fluorescent X-rays generated from the sample;
From the measurement result, a pre-edge peak that appears on the low energy side of the absorption edge of fluorescent X-rays is extracted, and based on the pre-edge peak, a chemical bonding state of an element existing in the sample is specified, and the pre-edge An analysis unit for analyzing the concentration of the element whose chemical bonding state is specified from the fluorescence intensity of the peak;
An X-ray analysis apparatus comprising:
(Additional remark 8) In the wavelength of the said pre-edge peak, It further has an incident angle adjustment mechanism which adjusts an incident angle so that the said X-ray may irradiate with respect to the said sample at 2 or more different incident angles,
The detector measures the fluorescence intensity of the pre-edge peak at each of the different incident angles,
The X-ray according to appendix 7, wherein the analysis unit obtains a depth distribution of the element with the specified chemical bonding state based on the fluorescence intensity of the pre-edge peak measured at the different incident angles. Analysis equipment.
(Supplementary Note 9) The detector measures an absorption edge spectrum of the fluorescent X-ray,
The analysis unit measures a fluorescence intensity at the pre-edge peak and a fluorescence intensity at an X-ray energy higher than the absorption edge from the X-ray absorption edge spectrum, and from the intensity ratio, the chemical bonding state The X-ray analyzer according to appendix 7, wherein the content concentration of the element identified by is calculated.
(Supplementary Note 10) Installed in the X-ray analyzer,
A procedure for extracting a pre-edge peak appearing on the low energy side of the absorption edge from an X-ray absorption edge spectrum obtained by measuring fluorescent X-rays generated from the sample;
A procedure for identifying a chemical bonding state of an element present in the sample based on the pre-edge peak;
An X-ray analysis program for executing a procedure for obtaining a content concentration of an element whose chemical bonding state is specified from the intensity of the pre-edge peak.

1 is a schematic configuration diagram of an X-ray analyzer according to an embodiment of the present invention. It is a graph which shows the incident angle dependence of the fluorescence X-ray spectrum of the X-ray absorption edge vicinity of a chromate film | membrane. FIG. 3 is an enlarged view near a pre-edge peak in the graph of FIG. 2. It is a graph which shows the incident angle dependence of the content rate of the hexavalent chromium which exists in a chromate film | membrane. It is a graph which shows the intensity | strength ratio of hexavalent chromium with respect to chromium whole quantity. It is a graph which shows distribution of the depth direction of hexavalent chromium. It is a graph used for correction | amendment of the detection result of hexavalent chromium by the elution method. It is a schematic block diagram of the analysis part of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 X-ray analyzer 10 Sample 11 Light source 12 Ion chamber 13 Detector (fluorescence intensity measurement part)
15 Analyzing unit 21 Pre-edge peak detecting unit 22 Chemical bond state specifying unit 23 Depth concentration distribution calculating unit

Claims (5)

Irradiating the sample with X-rays;
Measuring an X-ray absorption edge spectrum of fluorescent X-rays generated from the sample, and identifying a chemical bonding state of an element present in the sample from a pre-edge peak appearing on a low energy side of the absorption edge;
From the fluorescence intensity of the pre-edge peak, obtaining the content concentration of the element for which the chemical bonding state is specified;
A sample analysis method comprising: Irradiating the sample with two or more different incident angles at the wavelength of the pre-edge peak;
Measuring fluorescence intensity of pre-edge peaks at each of the different incident angles;
Obtaining a depth distribution of the element with the specified chemical bonding state based on the fluorescence intensity of the pre-edge peak at the different incident angles;
The sample distribution method according to claim 1, further comprising: Chemical analysis measures the concentration of elements present in a sample in a specific chemical bonding state,
3. The sample analysis correction method, wherein the measured concentration is corrected based on the content concentration obtained by the method according to claim 1 or 2. A light source for irradiating the sample with X-rays;
A detector for measuring the intensity of fluorescent X-rays generated from the sample;
From the measurement result, a pre-edge peak that appears on the low energy side of the absorption edge of fluorescent X-rays is extracted, and based on the pre-edge peak, a chemical bonding state of an element existing in the sample is specified, and the pre-edge An analysis unit for analyzing the concentration of the element whose chemical bonding state is specified from the fluorescence intensity of the peak;
An X-ray analysis apparatus comprising: Installed in the X-ray analyzer,
A procedure for extracting a pre-edge peak appearing on the low energy side of the absorption edge from an X-ray absorption edge spectrum obtained by measuring fluorescent X-rays generated from the sample;
A procedure for identifying a chemical bonding state of an element present in the sample based on the pre-edge peak;
An X-ray analysis program for executing a procedure for obtaining a content concentration of an element whose chemical bonding state is specified from the intensity of the pre-edge peak.

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