JP2000321222A - Filter for x-ray analysis and x-ray analyzer using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform the X-ray analysis of a sample without receiving adverse effect by X-ray of low energy having large intensity. SOLUTION: Incident X-rays 5 being white X-ray from an X-ray source and guided to a filter for X-ray analysis, part of white X-ray is totally reflected 7, and residual X-ray 9 transmit through the filter while they are refracted to irradiate a sample 15. An X-rays 16 reflected by the sample 15 are guided to an X-ray detection means 17 and the intensity corresponding to the energy of the reflected X-rays 16 is detected. The filter 1 for X-ray analysis is constituted by forming thin films 3, 4 of Au or Pt on both surfaces of a support plate 2 comprising Be.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a filter for selectively absorbing and attenuating X-rays used for analyzing a sample using X-rays, and an X-ray analyzer having the filter.

[0002]

2. Description of the Related Art Commercial prior art obliquely irradiates a sample with characteristic X-rays having a relatively high intensity from an X-ray source,
The intensity of the reflected X-ray is detected by X-ray detection means. The incident angle θ of the X-ray is equal to the reflection angle, and this angle θ
And an X-ray interference image can be obtained. This commercial prior art has a problem that the X-ray sources and the X-ray detection means disposed on both sides of the sample need to be angularly scanned with high precision so as to have the same angle θ. is there.

In order to solve this problem, as a prior art at the research stage, the X-ray source irradiates a sample with white X-rays, and the X-ray detecting means converts the energy of the X-rays, that is, the wavelength. It has a function to detect the corresponding intensity. Thus, the X-ray source and the X-ray detecting means do not need to be angularly displaced with high precision in conjunction with each other, and X-ray analysis of the sample can be performed.

When a sample has, for example, a structure in which a thin film is formed on a semiconductor substrate, of the white X-rays, the X-rays having a long wavelength equal to or less than the critical energy corresponding to the material of the sample are emitted from the semiconductor substrate and the thin film. X-rays that are totally reflected at the boundary surface of, that is, the contact surface, and have a short wavelength equal to or longer than the critical energy are reflected (ie, specular reflection).
I do. The X-ray detection means simultaneously detects an X-ray interference image of the X-ray totally reflected by the sample and the reflected X-ray,
Solves the problem of angular scanning.

A new problem of this prior art is that the intensity of the totally reflected X-rays incident on the X-ray detecting means is very large (10 ⁴ to 10 ⁶ times) as compared with the intensity of the reflected X-rays. Therefore, it is difficult to accurately detect the intensity corresponding to the energy of the reflected X-ray having the small intensity by the X-ray detecting means, and thus the method remains in the research stage and is being commercialized.

In order to solve this problem, it is easy to interpose a filter made of aluminum or the like for absorbing X-ray energy between the X-ray source and the sample or between the sample and the X-ray detecting means. Would be considered. In such a configuration, the energy absorbed by the filter depends on the material such as aluminum that constitutes the filter, and cannot fully absorb the X-rays that are totally reflected at a long wavelength equal to or less than the critical energy. The required reflected X-rays are also absorbed. Therefore, the intensity of the reflected X-ray cannot be detected accurately.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide an X-ray analysis filter and an X-ray analysis filter capable of performing accurate analysis by using X-rays reflected by a sample using white X-rays. An object of the present invention is to provide an X-ray analyzer.

[0008]

SUMMARY OF THE INVENTION The present invention provides a support plate made of a material having a small X-ray absorption coefficient and a thin film formed on a surface of the support plate and having a density higher than the density of the material of the support plate. And an X-ray analysis filter characterized by being a refraction transmission filter.

According to the present invention, the material of the support plate is
A material having a low density is selected so that X-rays are not absorbed or attenuated as much as possible, and is made of a material such as Be or diamond. The support plate is made as thin as possible so that absorption or attenuation of X-rays occurs as little as possible. A thin film is formed on one or both surfaces of the support plate, and therefore, the support plate is selected to have a thickness capable of maintaining its own shape and a thickness that does not bend naturally. The thickness of this support plate may be, for example, 10 μm.

The material of the thin film formed on the surface of the support plate is
In order to enable total reflection of the incident X-rays, a material having a density higher than that of the material of the support plate is selected.

The material of the thin film preferably has a density as large as possible, so that the critical angle φc at which total reflection occurs can be made as large as possible to facilitate the manufacture of the present device. As a material of the thin film, for example, A
u, Pt, Ni or the like may be used. In particular, by selecting Au and Pt, the function of preventing aging due to oxidation of the surface of the support plate can also be achieved. The thickness of the thin film may be, for example, 10 nm. The critical angle φc is, for example, 0.1 to 0.5 degrees.

By forming thin films on both surfaces of the support plate, the direction of X-rays incident on the X-ray analysis filter of the present invention, and one thin film, the support plate and the other thin film are transmitted and emitted in this order. The direction of the X-ray is parallel. Therefore, it is possible to easily irradiate the sample with the X-rays transmitted through the X-ray analysis filter or to detect the X-ray accurately by the X-ray detecting means. The materials of the two thin films are of the same material and of the same thickness in principle, but may be different from each other.

The present invention also provides (a) a total reflection type filter, comprising: a first support plate made of a first material; and a first support plate formed on one surface of the first support plate on the X-ray incidence side. A first thin film made of a second material having a density greater than the density of the first critical energy Ec at the surface of the first thin film.
A total reflection type filter that totally reflects X-rays of 1 or less; (b)
A refraction transmission filter to which X-rays totally reflected by the total reflection filter are incident, wherein the second support plate is made of a third material having a small X-ray absorption coefficient, and is formed on a surface of the second support plate; A fourth material having a density greater than that of the third material;
A second thin film made of a material, the second critical energy Ec being less than the first critical energy Ec1 at the surface of the second thin film.
An X-ray analysis filter comprising: a refraction transmission type filter that transmits two or more X-rays.

According to the present invention, as will be described later with reference to FIGS. 9 and 10, a range between the second critical energy Ec2 of the refraction transmission filter and the first critical energy Ec1 of the total reflection filter is used. X-rays having energy E are guided (Ec2 ≦ E ≦ Ec1), and X-rays having energy less than the second critical energy Ec2 and more than the first critical energy Ec1 are absorbed, so that a so-called bandpass filter is realized. By irradiating the sample with X-rays so that the X-ray energy in the band transmitted in this manner substantially matches the band of X-ray energy obtained by reflection from the sample, the X-ray energy obtained from the sample, for example, having a large intensity can be obtained. X-ray analysis of a sample can be performed accurately without being adversely affected by disturbing X-rays such as reflected X-rays.

The present invention also provides (a) a refraction-transmission type filter, wherein a first support plate made of a first material that transmits X-rays, and a first support plate formed on the surface of the first support plate and having a density of the first material. A first thin film made of a second material having a density higher than that of the first thin film, and a refraction transmission filter that transmits X-rays having a first critical energy Ec3 or more on the surface of the first thin film; and (b) a total reflection filter. A second support plate made of a third material, and a second support plate formed on one surface of the second support plate on the X-ray incident side and made of a fourth material having a density higher than the density of the third material. A total reflection type filter that includes a thin film and totally reflects X-rays having a second critical energy Ec4 exceeding the first critical energy Ec3 on the surface of the second thin film. is there.

According to the present invention, as will be described later with reference to FIGS. 11 and 12, the range between the first critical energy Ec3 of the refraction transmission type filter and the second critical energy Ec4 of the total reflection type filter is not more than. A so-called band-pass filter that transmits X-rays having energy E is realized (E
c3 ≦ E ≦ Ec4). Such transmission bands Ec3 to Ec
By making 4 substantially coincide with the energy band of reflected X-rays from the sample, X-ray analysis of the sample can be performed accurately.

The refraction transmission type filter can be said to be a so-called high-pass filter that transmits X-rays having energy equal to or higher than the critical energies Ec2 and Ec3. The total reflection type filter can be said to be a so-called low-pass filter that totally reflects and guides the X-rays having the energy equal to or less than the critical energies Ec1 and Ec4.

The angle θ at which the X-rays are incident on the sample may be selected according to the energy range in which the detection sensitivity of the X-ray detecting means is good. The energy of the reflected X-ray is determined depending on the incident angle θ of the X-ray to the sample.

In the present invention, the X-ray analysis filter, which is the high-pass filter of the first aspect, may also be integrally attached to the X-ray source.

The present invention also includes a white X-ray source, the above-described X-ray analysis filter, and X-ray detecting means for receiving the X-ray reflected by the sample and detecting an intensity corresponding to the X-ray energy. An X-ray analyzer characterized by the following.

According to the present invention, X-rays from a white X-ray source are guided to the X-ray analysis filter 1 shown in FIGS. 1 and 2, and a part of the white X-rays is totally reflected by the filter and transmitted through the filter. By irradiating only the remaining X-rays to the sample, it is possible to prevent the totally reflected X-rays having a large intensity from being guided to the X-ray detecting means, and to accurately perform the X-ray analysis of the sample.

By irradiating the sample with white X-rays,
The distribution of the intensity of the X-ray energy obtained by reflection from the sample has a characteristic that the intensity decreases almost exponentially, that is, exponentially with an increase in the energy. The intensity distribution of the X-ray energy transmitted through has a characteristic that the intensity increases almost exponentially as the energy increases. Therefore, the materials for the support plate and the thin film that determine the critical energy should be selected so that the energy range for the X-ray analysis of the reflected X-rays obtained from the sample substantially matches the range of the X-rays transmitted through the filter. Thereby, the X-ray analysis of the sample can be performed accurately. For example, when the sample has a structure in which a thin film is formed on a substrate, the thickness t of the thin film can be accurately detected. The X-ray analysis filter may have the configuration shown in FIG. 1 or the configuration shown in FIG. 13.
Further, the band-pass filters shown in FIGS. 9 to 12 may be used.

The present invention also provides a white X-ray source for irradiating a sample with X-rays, and the X-rays among the X-rays reflected by the sample.
X-ray analysis filter and X-ray analysis filter
An X-ray analyzer provided with X-rays, and X-ray detecting means for detecting an intensity corresponding to X-ray energy.

According to the present invention, the sample is irradiated with white X-rays, and the X-rays reflected by the sample by irradiating the sample with white X-rays are guided to the X-ray analysis filter 30 in FIG. Some X-rays are totally reflected, and only the remaining X-rays are refracted and transmitted, and guided to the X-ray detecting means. Thus X from the sample
X-rays that interfere with the line analysis are removed and the analysis can be performed. Therefore, X-ray analysis of the sample can be performed accurately and with a wide dynamic range.

Further, according to the present invention, the X-ray analysis filter is the above-mentioned X-ray analysis filter, and the total reflection type filter is
It is characterized by being provided integrally with the X-ray source so as to be angularly displaceable relative to the sample.

According to the present invention, when changing and adjusting the incident angle θ of the X-rays incident on the sample, the total reflection type filter and the total reflection type filter among the total reflection type filter and the refraction transmission type filter constituting the band-pass filter are used. Is angularly displaced integrally with the X-ray source. As a result, X-rays emitted from the X-ray source can be accurately incident on the total reflection type filter at the critical angle φc, and the X-ray analysis work becomes easy.

According to the present invention, the X-ray analysis filter used in the X-ray analyzer may be the high-pass filter of FIGS. 1 and 13 or the band-pass filter of FIGS.

According to the present invention, the X-ray analysis filter is an X-ray analysis filter having the configuration shown in FIGS. 1 and 13, and is provided so as to be angularly displaceable integrally with the X-ray source. And

According to the present invention, not only the total reflection type filter constituting the bandpass filter but also the refraction transmission type filter is angularly displaced integrally with the X-ray source. Thus, the operability can be improved by attaching the relatively small band-pass filter integrally to the X-ray source.

The present invention is further characterized by further comprising means for moving and positioning the sample to a predetermined X-ray analysis position.

According to the present invention, as shown in FIG. 7, a large number of samples are automatically analyzed by moving a sample measured by the present X-ray analyzer to a predetermined X-ray analysis position and positioning it. It becomes possible to do. For example, by implementing the present invention in connection with a semiconductor manufacturing apparatus for manufacturing a semiconductor element such as a semiconductor memory, the thickness of a semiconductor thin film formed on a semiconductor substrate can be accurately determined for each manufactured semiconductor element. It becomes possible to detect.

Further, the present invention further comprises a reaction container for accommodating the sample, wherein at least a part of the reaction container is made of a material that transmits X-rays irradiated to the sample and X-rays reflected by the sample, Is characterized in that a reaction for forming a thin film on a substrate is performed.

According to the present invention, as shown in FIG. 8, X-ray analysis of a sample being reacted in a reaction vessel can be automatically performed. X-rays are transmitted and guided into an airtight reaction vessel, and X-rays reflected by the sample are guided out of the reaction vessel, and X-rays are emitted.
Perform line analysis. This allows, for example, CV
The thickness, density, surface roughness, and the like of a thin film on a semiconductor substrate formed by D (chemical vapor deposition) can be detected in real time.

[0034]

FIG. 1 is a sectional view of an X-ray analysis filter 1 according to an embodiment of the present invention. This filter 1
Is formed by forming thin films 3 and 4 on both surfaces of the support plate 2. Incident X-rays 5 which are white X-rays incident at an incident angle φ are totally reflected on the surface 6 of the thin film 3, and the totally reflected X-rays are emitted as indicated by reference numeral 7. Of the incident X-rays 5, the remaining X-rays are totally reflected at the interface 2 a of the support plate 2 as indicated by reference numeral 8 and as indicated by reference 10 at the other interface 2 b. It is totally reflected and also refracted through the filter 1 as indicated by reference numeral 9. The incident X-ray 5 and the refraction-transmitted X-ray 9 are parallel in one virtual plane parallel to the plane of FIG.

The support plate 2 absorbs transmitted X-rays as much as possible.
It is made of a material having a small density that does not attenuate, that is, a material having a small X-ray absorption coefficient, for example, Be. Support plate 2
Is selected to a value that does not cause distortion such as bending or deformation when the present filter is used.
It may be 0 μm.

The thin films 3, 4 are made of, for example, the same material and have a higher density than the support plate 2,
Enables total reflection at the thin film surface 6. The material of such thin films 3 and 4 may be, for example, Au, Pt, Ni, etc. In particular, Au and Pt are used from the viewpoint of preventing both surfaces of the support plate 2 from being oxidized and contaminated. preferable. Furthermore, such metals Au and Pt have a high density, and as a result, the critical angle φ of total reflection on the thin film surface 6 is increased.
It is preferable to make c as large as possible and to facilitate handling of the present filter 1. The critical angle φc is, for example, 0.1 to 0.5 degrees. Thicknesses t3 and t4 of thin films 3 and 4
May be, for example, 10 nm. The front shape of the filter 1 may be, for example, 15 mm long × 5 mm wide.

FIG. 2 is a simplified system diagram showing the overall configuration of an X-ray analyzer 11 using the X-ray analysis filter 1 shown in FIG. Continuous X from white X-ray source 12
A white X-ray having a line spectrum is incident on the X-ray analysis filter 1 through a slit 13 as shown by a reference numeral 5, and the transmitted X-ray 9 passes through another slit 14 and is incident on a sample 15 at an incident angle θ. Incident. The X-rays 16 specularly reflected by the sample 15 are guided to the X-ray detecting means 17. The X-ray detector 17 detects an intensity corresponding to the X-ray energy of the X-ray 16 reflected by the sample 15. X like this
The line detecting means 17 is a semiconductor element X-ray detector (abbreviated as SS).
D) and the like.

FIG. 3 is a diagram showing a spectrum of white X-rays obtained by the X-ray source 12. The horizontal axis in FIG. 3 is the X-ray energy, and the vertical axis is the intensity of the X-ray energy. In FIG. 3, the horizontal axis is an equally spaced scale, and the vertical axis is a logarithmic scale, and the characteristics are shown in a semilogarithmic graph. This is the same not only in FIG. 3 but also in the graphs having the respective spectral characteristics shown in FIGS. 4 to 6, 10 and 12. In the X-ray analysis of the present invention, it is important to use white X-rays 18 over a wide energy range, and the characteristic X-rays 19 are not used for X-ray analysis.

FIG. 4 shows the total reflection X of the X-ray analysis filter 1.
FIG. 9 is a diagram for explaining the spectral characteristics of a line 7 in a simplified manner. In FIG. 4 and the following FIG. 5, for convenience of description, the white X-ray 5 is described assuming that the intensity is constant over a wide range of X-ray energy. White X as shown in FIG.
When the ray 5 is incident on the filter 1, the X-ray 7 totally reflected by the thin film surface 6 has an energy in the range below the critical energy Ec in FIG. 4 and is indicated by a characteristic 21 a.

FIG. 5 is a diagram for explaining the characteristics of the X-ray analysis filter 1. In FIG. 4 described above, the total reflection X-ray 7
Although the spectral characteristics of the total reflection X-ray 7 are shown by the reference numeral 21a for simplicity, in fact, the spectral characteristics of this total reflection X-ray 7 are as shown by the line 21 in FIG. In the above range of the X-ray energy, as the X-ray energy increases, the intensity has a characteristic indicated by a line 22 whose intensity decreases almost exponentially. Therefore, of the incident white X-rays 5,
The spectral characteristic 23 of the X-ray 9 transmitted through the filter 1 without being totally reflected has a characteristic 24 which is higher than the critical energy Ec and whose intensity increases almost exponentially with an increase in energy. In the range where the X-ray energy of the characteristic 23 is further larger, the intensity of the transmitted X-ray 9 is substantially constant.

FIG. 6 shows a case where white X-rays from the X-ray source 12 are incident on the sample 15 so that the incident angle θ becomes the critical angle θc, and all the reflected X-rays are X-ray detected. FIG. 7 is a diagram showing spectrum characteristics when detected by means 17. X-rays having a critical energy Ec15 or less of the sample 15 are guided to the X-ray detecting means 17 with a large intensity by being totally reflected. The intensity of the X-ray having energy equal to or higher than the critical energy Ec15 shows the characteristic indicated by the line 26 according to the structure of the sample 15. Critical energy Ec
The peak interval ΔE, which is the maximum value of the X-ray intensity characteristic 27 at an energy of 15 or more, corresponds to the thickness t of the thin film when the sample 15 has a configuration in which the thin film is formed on the substrate. A characteristic line 28 connecting the peaks of the characteristic 27 in the energy range equal to or higher than the critical energy Ec15 is substantially a straight line on the graph on the semilog scale of FIG.
The reflected X-rays due to 5 have the property that their intensity decreases almost exponentially with increasing energy. The critical energy Ec of the filter 1 is selected to be a value close to the critical energy Ec15 of the sample 15.

FIG. 6 shows the X-ray detecting means 1 as described above.
7 shows the spectral characteristics of the reflected X-rays 16 by the sample 15 detected by 7. Transmitted X-ray 9 of filter 1
Has the characteristic shown by the line 24 in FIG. 5 described above, and the intensity of the transmitted X-ray 9 increases almost exponentially as the X-ray energy increases. On the other hand, the intensity of the reflected X-ray 16 obtained when the sample 15 is irradiated with white X-ray has a characteristic line 28 which is almost exponential and decreases as shown in FIG. Therefore, in the range of the X-ray energy equal to or higher than the critical energies Ec and Ec15, the characteristic 27 corresponding to the structure of the sample 15 is obtained.
Can be obtained clearly. Also, among the white X-rays 5,
Since the X-rays 7 having a large intensity and totally reflected are not incident on the X-ray detecting means 17, the measurement accuracy of the reflected X-rays 16 by the sample 15 can be improved. Further, the film thickness of the sample can be determined from ΔE, and the curve can be fitted to a theoretical curve to calculate the density and surface roughness of the thin film.

In another embodiment of the present invention, FIG.
Is provided between the sample 15 and the X-ray detecting means 17 as shown by the reference numeral 30 instead of interposing the X-ray analysis filter 1 shown in FIG. It may be configured as follows. The sample 15 is irradiated with white X-rays 5 from the X-ray source 12, and part of the reflected X-rays 16 from the sample 15 is incident on the X-ray analysis filter 30 at a critical angle and totally reflected, and the remaining Are transmitted through the filter 30 and guided to the X-ray detecting means 17. Such a configuration also enables accurate X-ray analysis of the sample 15 with a wide dynamic range in the same manner as described above.

FIG. 7 is a system diagram schematically showing the overall configuration of an X-ray analyzer 31 according to another embodiment of the present invention. This embodiment is similar to the embodiment of FIGS. 1 to 6 described above, and corresponding parts are denoted by the same reference numerals.
Particularly, in this embodiment, the sample 15 is
By (2), it moves to a predetermined X-ray analysis position and is automatically positioned. In this manner, the plurality of samples 15 can be sequentially and automatically exchanged, and the X-ray analysis for each sample 15 can be automatically performed. The X-ray source 12 and the filter 1 are angularly displaced by driving means 33 and 34 around an axis C extending in a direction perpendicular to the X-ray direction as shown by reference numerals 35 and 35a, and the sample 15 is moved. Can be adjusted to the optimum energy range and the incident angle θ of the X-rays irradiated to the laser beam. The operation of the driving units 33 and 34 can be controlled by a control circuit 36 realized by a microcomputer or the like.

The X-ray source 12 and the filter 1 may be individually driven by the driving means 33 and 34 as described above. In another embodiment of the present invention, the filter 1 is attached and fixed to an X-ray source 12. Thus, the configuration in which white X-rays from the X-ray source 12 are incident on the filter 1 at the critical angle φc is always maintained. According to such a configuration, the configuration is simplified and operability is improved.

FIG. 8 is a perspective view showing a simplified configuration of a part of another embodiment of the present invention. In a semiconductor manufacturing apparatus 37 for manufacturing a semiconductor device such as a semiconductor memory, a sample 15 which is a semiconductor device to be manufactured is arranged in an airtight reaction vessel 38. In the sample 15, a semiconductor thin film is formed on a surface of a semiconductor substrate by, for example, CVD (chemical vapor deposition).
A film is grown and formed by such a method. The reaction container 38 is configured such that a window member 39 is provided at a position where a path through which the X-rays 9 are incident on the sample 15 is formed. The window member 40 is located at a position where the reflected X-rays 16 from the sample 15 are guided.
Is provided. These window members 39 and 40 constitute a part of the reaction vessel 38, and easily transmit X-rays 9 and 16,
It is made of a material that does not absorb or attenuate, such as Be. Thus, in the semiconductor manufacturing apparatus 37, the semiconductor element can be manufactured while observing the film formation state of the sample 17 in real time by X-ray analysis. Other configurations in FIG. 8 are the same as those in the above-described embodiment.

FIG. 9 is a simplified system diagram of an X-ray analysis filter 42 according to another embodiment of the present invention. The X-ray analysis filter 42 includes a total reflection filter 43 and a refraction transmission filter 44. The total reflection filter 43 is
Although it has a configuration similar to that of the filter 1 shown in FIG. 1 described above, in this total reflection filter 43, the thin film 3 is formed on one surface of the substrate 2, and the other thin film 4 may be omitted. The white X-ray 5 passes through the total reflection filter 43.
At a critical angle φc1, and the total reflection X-ray 45 is incident on a refraction / transmission type filter 44 at a critical angle φc2. The refraction transmission filter 44 has a configuration similar to that of the above-described filter 1 of FIG.

FIG. 10 is a graph showing the spectral characteristics of the X-ray analysis filter 42 shown in FIG. The total reflection filter 43 has a characteristic 48 and totally reflects X-rays having a critical energy Ec1 or less. Refractive transmission filter 4
4 has a characteristic 49 and transmits X-rays having a critical energy equal to or higher than Ec2 (Ec2 <Ec1). Thus, the X-rays 47 within the range of the X-ray energies Ec2 to Ec1 are emitted.
The refraction transmission filter 44 emits total reflection X-rays 46,
This total reflection X-ray 46 is not used for X-ray analysis of the sample. Thus, a so-called band-pass filter that emits X-rays having energy E in the band of X-ray energies Ec2 to Ec1 as shown in FIG. 10 is realized (Ec).
2 ≦ E ≦ Ec1).

At least the total reflection type filter 43 of the X-ray analysis filter 42 is used integrally with a white X-ray source. This ensures that the X-rays 5 from the white X-ray source are always incident on the filter 43 at the critical angle φc1. Along with the total reflection filter 43, a refraction transmission filter 44 may be integrally attached to the X-ray source.

FIG. 11 is a simplified system diagram of an X-ray analysis filter 51 according to still another embodiment of the present invention.
This X-ray analysis filter 51 is such that the white X-ray 5 has a critical angle φ.
It includes a refraction-transmission type filter 52 incident at c3 and a total reflection type filter 54 at which X-rays 53 transmitted through the refraction-transmission type filter 52 are incident at a critical angle φc4. The X-ray 55 totally reflected by the total reflection filter 54 is used for X-ray analysis of the sample. The refraction transmission filter 52 has a configuration similar to the filter 1 shown in FIG. 1 described above. The total reflection filter 54 has a configuration similar to that of the total reflection filter 43 shown in FIG. 9 described above, has a configuration including the support plate 2 and one thin film 3 in FIG. One thin film 4 may be omitted.

FIG. 12 is a diagram showing the spectral characteristics of the X-ray analysis filter 51 shown in FIG. The refraction transmission filter 52 transmits X-rays having a critical energy of Ec3 or more,
It is transmitted as shown by the characteristic 56. The total reflection filter 54 totally reflects X-rays having a critical energy Ec4 or less as shown by a characteristic 57 (Ec3 <Ec4). Thus, when white X-rays enter the X-ray analysis filter 51,
The totally reflected X-rays 55 emit X-rays having an energy E in a band of energies Ec3 to Ec4, so that a so-called bandpass filter is realized (Ec3 ≦ E ≦ Ec4).

The thin film 3 of the filter 1 may be composed of a plurality of layers, and the same applies to the thin film 4.

FIG. 13 is a sectional view of an X-ray analysis filter 1a according to another embodiment of the present invention. This X-ray analysis filter 1a is similar to the embodiment shown in FIG. 1, and corresponding portions are denoted by the same reference numerals. In this embodiment, the thin film 3 is formed only on the X-ray incident surface 2a of the support plate 2, and no thin film is provided on the emission surface 2b. In the X-ray analysis filter 1a shown in FIG. 13, the angle φ of the incident X-ray 5 and the X-ray 9
(Φ ≠ φa). Therefore, in the X-ray analysis filter 1a of FIG. 13, since the direction of the incident X-ray 5 and the direction of the X-ray 9 which is refracted and transmitted are not parallel, there is a weak point that it is difficult to handle. The object of the present invention can be sufficiently achieved, and the present invention includes such an X-ray analysis filter 1a shown in FIG.

As another type of X-ray analysis filter, the thin film 3 may not be provided on the X-ray incident side as shown in FIG. The present invention also includes this mode.

[0055]

According to the first aspect of the present invention, by forming a thin film on the surface of the support plate, a part of the incident white X-ray is totally reflected and the remaining X-ray is refracted and transmitted. Accordingly, the analysis result of the sample can be accurately obtained by the transmitted X-rays without being adversely affected by the totally reflected X-rays having a large intensity.

The characteristic of the X-ray transmitted through the filter is X-ray
There is a portion where the intensity increases exponentially as the line energy increases, and thus by utilizing this range of X-ray energies, the results of the X-ray analysis of the sample can be made without being adversely affected by interfering X-rays. , Has a wide dynamic range and can be obtained accurately. White X on sample
When irradiated with X-rays, the X-rays reflected by the sample have the characteristic that their intensity is almost exponentially reduced as the X-ray energy increases, and the X-ray energy range of such a sample falls within the range of the present filter. Are approximately equal to each other, even in a region where the X-ray energy is high, a large intensity of the X-ray reflected by the sample can be obtained.

Further, according to the present invention, by changing the material combination of the substrate and the thin film, it is easy to change and set the critical energy Ec at the time of total reflection at the interface between the substrate and the thin film. It is possible to realize an X-ray analysis filter suitable for various kinds of applications.

According to the second and third aspects of the present invention, by combining a total reflection type filter and a refraction transmission type filter, a desired band of X-ray energy can be absorbed and attenuated, that is, a bandpass filter can be realized. It becomes possible to do.
This allows the X-ray analysis of the sample to be accurately achieved without being adversely affected by interfering X-rays.

According to the fourth and fifth aspects of the present invention, before or after irradiating the sample with white X-rays, the white X-rays which have transmitted through the filter for X-ray analysis and are other than the X-rays totally reflected among the white X-rays X-ray analysis is performed using only the remaining transmitted X-rays of the above, and guided to the X-ray detection means, whereby the low-energy X-rays having a large intensity which does not contribute to the X-ray analysis of the sample are provided to the X-ray detection means. This prevents the sample from being incident, and allows the sample to be accurately analyzed without the adverse effects of the disturbing X-rays.

According to the sixth aspect of the present invention, the total reflection type filter constituting the band pass filter is angularly displaced integrally with the white X-ray source relative to the surface of the sample,
Thus, the angle of incidence θ of the X-rays on the sample can be changed and adjusted in a state where the total reflection of the X-rays by the total reflection type filter is always enabled. Therefore, for example, it is possible to easily select the incident angle θ of the sample corresponding to the range of the X-ray energy in which the sensitivity of the X-ray detecting means is good and perform the X-ray analysis of the sample, and the operability is good. At the same time, the configuration can be simplified.

According to the present invention, not only the total reflection type filter constituting the band pass filter but also the refraction transmission type filter can be integrally angularly displaced together with the X-ray source. The structure can be simplified by integrating the refraction transmission type filter and the X-ray source.

According to the eighth aspect of the present invention, the X-ray analysis of the sample can be continuously and automatically performed by exchanging and moving the sample to the position where the X-ray analysis is performed. become able to.

According to the ninth aspect of the present invention, for example, when a thin film is formed in a reaction vessel of a semiconductor manufacturing apparatus or the like, the film formation state of the thin film can be analyzed in real time by X-rays. As a result, the analysis of the sample can be known at the time of manufacturing, the adjustment of the film formation reaction and the like can be easily performed, and the yield of film formation can be improved.

[Brief description of the drawings]

FIG. 1 is an X-ray analysis filter 1 according to an embodiment of the present invention.
FIG.

FIG. 2 is a simplified system diagram showing an overall configuration of an X-ray analyzer 11 using the X-ray analysis filter 1 shown in FIG.

FIG. 3 is a diagram showing a spectrum of white X-rays obtained by an X-ray source 12.

FIG. 4 is a diagram for simply describing spectral characteristics of total reflection X-rays 7 of the X-ray analysis filter 1.

FIG. 5 is a diagram for explaining characteristics of the X-ray analysis filter 1;

FIG. 6 shows a case where white X-rays from the X-ray source 12 are incident on the sample 15 so that the incident angle θ becomes the critical angle θc, and the total reflection and all of the reflected X-rays are performed by the X-ray detection unit 17.
FIG. 5 is a diagram showing spectrum characteristics when detection is performed in FIG.

FIG. 7 is a simplified system diagram showing the overall configuration of an X-ray analyzer 31 according to another embodiment of the present invention.

FIG. 8 is a simplified perspective view showing a partial configuration of another embodiment of the present invention.

FIG. 9 is a simplified system diagram of an X-ray analysis filter 42 according to another embodiment of the present invention.

10 is a graph showing the spectral characteristics of the X-ray analysis filter 42 shown in FIG.

FIG. 11 is a simplified system diagram of an X-ray analysis filter 51 according to still another embodiment of the present invention.

12 is a diagram showing the spectral characteristics of the X-ray analysis filter 51 shown in FIG.

FIG. 13 is a cross-sectional view of an X-ray analysis filter 1a having a different form from the analysis filter of FIG.

[Explanation of symbols]

 1, 1a, 30, 42, 51 Filter for X-ray analysis 2 Support plate 3, 4 Thin film 5 Incident X-ray 6 Surface 7, 8, 45, 46 Total reflection X-ray 9 Refractive transmission X-ray 12 White X-ray source 15 Sample Reference Signs List 17 X-ray detecting means 18 White X-ray 32 Positioning means 33, 34 Driving means 36 Control circuit 37 Semiconductor manufacturing apparatus 38 Reaction vessel 39, 40 Window member 43, 54 Total reflection filter 44, 52 Refraction transmission filter

Claims (9)

[Claims] 1. A refraction transmission filter comprising: a support plate made of a material having a small X-ray absorption coefficient; and a thin film formed on a surface of the support plate and made of a material having a density higher than the density of the material of the support plate. An X-ray analysis filter, characterized in that: 2. (a) A total reflection type filter, comprising: a first support plate made of a first material; and one surface of the first support plate on an X-ray incidence side,
A first thin film made of a second material having a density higher than the density of the first material, wherein at the surface of the first thin film, X not more than a first critical energy Ec1
(B) a refraction-transmission type filter into which X-rays totally reflected by the total reflection type filter are incident, and a second material made of a third material having a small X-ray absorption coefficient. A support plate, and a second thin film formed on a surface of the second support plate and made of a fourth material having a density higher than a density of the third material, wherein at a surface of the second thin film, less than a first critical energy Ec1 A refraction transmission type filter that transmits X-rays having a second critical energy Ec2 or more. 3. A refraction transmission type filter, comprising: a first support plate made of a first material that transmits X-rays; and a first support plate formed on a surface of the first support plate and having a density higher than a density of the first material. A first thin film made of a second material having a high density, and a refraction transmission filter that transmits X-rays having a first critical energy Ec3 or more on the surface of the first thin film; and (b) a total reflection filter. A second support plate made of a third material, and formed on one surface of the second support plate on the X-ray incident side;
A second thin film made of a fourth material having a density higher than the density of the third material, wherein the surface of the second thin film totally reflects X-rays having a second critical energy Ec4 exceeding the first critical energy Ec3 and equal to or less than a second critical energy Ec4. A filter for X-ray analysis, comprising: a total reflection filter. 4. A white X-ray source, an X-ray analysis filter according to claim 1, and an X-ray reflected by a sample, the intensity of which is given by X-ray energy. An X-ray analyzer comprising: an X-ray detection unit for detecting. 5. A white X-ray source for irradiating a sample with X-rays, an X-ray analysis filter according to claim 1 among X-rays reflected by the sample, X-rays An X-ray analysis apparatus comprising: an X-ray detection unit that receives transmitted X-rays from an analysis filter and detects an intensity corresponding to X-ray energy. 6. An X-ray analysis filter according to claim 2 or 3, wherein the total reflection type filter is integrated with the X-ray source and has an angle relative to the sample. The X-ray analyzer according to claim 4, wherein the X-ray analyzer is displaceably provided. 7. The X-ray analysis filter according to claim 1, wherein the X-ray analysis filter is provided so as to be able to be angularly displaced integrally with the X-ray source. Line analyzer. 8. The X-ray analyzer according to claim 4, further comprising means for moving and positioning the sample at a predetermined X-ray analysis position. 9. The method according to claim 9, further comprising a reaction container for storing the sample.
At least a portion of the reaction vessel is made of a material that transmits X-rays irradiated to the sample and X-rays reflected by the sample, and in the reaction vessel, a reaction is performed in which a thin film is formed on a substrate. The X-ray analyzer according to any one of claims 4 to 8, wherein