JPH05118999A - X-ray analyzing device - Google Patents

Abstract

PURPOSE:To approach both an X-ray collimator and a sample observing means to a sample, set an X-ray spot form small, and improve space resolution of X-ray analysis by setting an X-ray beam irradiating position and a sample observing position at a determined distance, moving the sample in a determined distance to conform the X-ray beam irradiating position to the sample observing area. CONSTITUTION:A sample observing means 10 formed of a light source 11, a beam splitter 14, an objective lens 15, and a collimating plate 6, and an image pickup element 19 is provided at a determined distance to an X-ray beam irradiating position. After the analyzing target of a sample is guided to a determined position of the collimating plate image, a sample 4 is precisely carried by the distance of the coordinate displacement data by a sample carrying means and precisely positioned in an X-ray beam irradiating position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray analyzer for analyzing sample information by irradiating a sample with an X-ray beam and detecting scattered X-rays, fluorescent X-rays, etc. The present invention relates to an X-ray analysis apparatus equipped with a sample observation means for identifying

[0002]

2. Description of the Related Art Conventionally, in an X-ray analyzer capable of associating an X-ray beam irradiation region on a sample with a sample observation region, the sample is fixed to a sample holding means such as an XY stage. It has been practiced to set the X-ray beam irradiation position and the sample observation position at the same place and confirm the analysis region of the sample.

FIG. 2 shows an example of a conventional X-ray analysis apparatus. The overall schematic configuration is such that the X-ray beam 2 is obliquely irradiated to the surface of the sample 4 at an angle of about 45 degrees, and the sample is observed. The direction is set substantially perpendicular to the surface of the sample 4.

The X-ray beam 2 emitted from the X-ray beam generator 1 is irradiated onto the surface of the sample 4 in a spot shape via the X-ray collimator 3. The X-ray collimator 3 controls the diameter and size of the X-ray beam 2, and for example, a pinhole collimator having a small hole formed in a metal plate is used. By reducing the X-ray spot irradiated on the surface of the sample 4, it is possible to improve the spatial resolution of sample analysis. However, the shape of the X-ray spot depends on the pinhole diameter of the X-ray collimator 3 and the sample 4. It depends on various factors such as the distance of the X-ray collimator 3, the distance between the X-ray beam generator 1 and the X-ray collimator 3, the shape of the X-ray source on the target of the X-ray beam generator 1, and the like. Generally, the shorter the distance between the sample 4 and the X-ray collimator 3, the more accurately the X-ray spot shape is controlled to the pinhole shape.
It is required to be as close as possible to.

On the other hand, the sample observing means 10 for confirming the X-ray beam irradiation area on the sample 4 is also arranged near the area. As the sample observation means 10, for example, a combination of an optical microscope and an image pickup device is used. Since the objective lens 15 generally has a short focal length, the light receiving side of the sample observing means 10 is required to be as close to the sample 4 as possible.

When the sample 4 is irradiated with the X-ray beam 2, detected X-rays 5 such as scattered X-rays and fluorescent X-rays are emitted,
This is detected by the X-ray detection means 6 and converted into an electric signal, and various data analysis is performed by the signal processing device 7 in the subsequent stage.

FIG. 4 shows another example of the conventional X-ray analysis apparatus. The overall schematic structure is such that the X-ray beam 2 is irradiated in a direction substantially perpendicular to the surface of the sample 4 and the sample observation direction is shown. Is also set substantially perpendicular to the surface of the sample 4.

The X-ray beam 2 emitted from the X-ray beam generator 1 is irradiated onto the surface of the sample 4 in spots via the X-ray collimator 3. The sample observing means 10 for observing the X-ray beam irradiation region of the sample 4 is arranged in the vicinity of the region, but a perforated mirror 20 is used to prevent interference with the X-ray beam 2. The X-ray beam 2 goes straight through the hole, while the sample observation light is reflected by the reflection surface of the perforated mirror 20 toward the sample observation means 10. The main difference from the X-ray analyzer shown in FIG. 2 is that the X-ray beam irradiation direction and the sample observation direction are coaxial. The detection of scattered X-rays and fluorescent X-rays from the sample and the signal processing are the same as in FIG.

[0009]

However, in the configuration of FIG. 2, in order to set the X-ray spot shape on the sample 4 uniformly and to a small spot diameter as necessary, X
The request to bring the line collimator 3 closer to the sample 4 and X
The request to bring the sample observing means 10 closer to the sample 4 in order to confirm the irradiation area of the beam causes a competition between the X-ray collimator 3 and the sample observing means 10, and a configuration in which both requirements are compromised. There was a problem that I had to take it. That is, if the X-ray collimator 3 is brought closer to the sample 4, it becomes difficult to observe the sample, while if the sample observing means 10 is brought closer to the sample 4, it becomes difficult to irradiate the X-ray beam.

Further, since the X-ray beam irradiation direction and the sample observation direction are not coaxial, the surface of the sample 4 is an irregular irregular surface, or the entire sample is deformed such as warped or bent, There is a problem that the X-ray spot position and the focus position for observing the sample are displaced. FIG. 3 shows such a state, FIG. 3a is a cross-sectional view of the sample 4 in which the surface is recessed, and FIG. 3b is a cross-sectional view of the sample 4 in which the surface is deformed into a convex shape. In FIGS. 3A and 3B, the sample observation direction is substantially perpendicular to the sample surface, the objective lens 15 of the sample observation means 10 collects light from the sample, and the sample 4 is deformed so that the focal position is changed. Even if the position shifts, it is possible to always observe a fixed position by automatic or manual focus adjustment performed by moving the sample observing means 10 or the sample 4 in the optical axis direction. However, since the X-ray beam 2 is obliquely incident on the sample 4, the X-ray beam irradiation position is displaced due to the deformation of the sample 4, and the phenomenon that the X-ray beam does not coincide with the observation position occurs. Particularly, in the case of focus adjustment for moving the sample 4 in the optical axis direction, the X-ray beam 2
Since the X-ray beam irradiation position is moved along with the movement of the sample 4 due to the oblique incidence of, the sample observation position and the X-ray beam irradiation position can be made to coincide with each other. Since the X-ray spot diameter is reduced to, for example, about 20 to 30 μm, it becomes impossible to completely match the sample observation position and the X-ray beam irradiation position, and especially the sample surface is a mirror surface. When the optical reflectance is high, it is difficult to determine the focus,
This is a very difficult adjustment.

Further, when the X-ray beam irradiation direction is incident at an angle θ with respect to the sample normal, for example, when the X-ray spot shape is a circle, an elliptical spot shape increased by the reciprocal of COS (θ) in the beam inclination direction. Therefore, it is difficult to irradiate a narrow region as the X-ray irradiation angle is inclined.

Next, even in the configuration of FIG. 4, competition occurs between the X-ray collimator 3 and the sample observing means 10 and there is a problem similar to that of the system of FIG. 2 described above. Since the observation direction is coaxial and the X-ray beam irradiation direction is perpendicular to the sample, the problem caused by oblique irradiation of the X-ray beam is solved. However, it is necessary to dispose the perforated mirror 20 in the vicinity of the sample in order to make the X-ray beam irradiation direction and the sample observation direction coaxial, which causes a new problem that the distance between the X-ray collimator 3 and the sample 4 becomes long. Occurs in. That is, as shown in FIG. 5, the X-rays emitted from the X-ray source 8 formed on the target of the X-ray beam generator 1 are focused by the X-ray collimator 3 and the sample 4
However, since the distance between the X-ray collimator 3 and the sample 4 is short in FIG. 5a, it is possible to form the X-ray spot diameter on the sample 4 small, but in FIG. Since the distance between the sample 3 and the sample 4 is long, a phenomenon called so-called blurring in which the X-ray spot diameter on the sample 4 becomes large occurs. Therefore, the configuration of FIG. 4 has a problem that the X-ray spot diameter cannot be formed so small.

2 and 3, a positioning operation for matching the X-ray beam irradiation position and the observation position by the sample observation means 10 is indispensable, and the X-ray wavelength and the sample observation wavelength (for example, Since the visible light is different and the detection means is naturally different, the alignment is very difficult. Furthermore, the X-ray beam generator 1 and the sample observation means 10
It was necessary to perform the alignment every time the battery was replaced or repaired, and a great amount of labor was wasted in the alignment.

In order to solve these problems, the present invention provides
It is an object of the present invention to provide an X-ray analyzer capable of easily associating an X-ray beam irradiation region on a sample with a sample observation region.

[0015]

In order to achieve the above-mentioned object, an X-ray analysis apparatus of the present invention comprises an X-ray beam irradiation means equipped with an X-ray beam generator and an X-ray collimator, an X-ray detection means, and sample observation. An X-ray analysis apparatus comprising means and sample transport means, wherein an X-ray beam irradiation position and a sample observation position are set at a predetermined distance, and the sample moves on the sample by the predetermined distance. The X-ray beam irradiation area and the sample observation area are made to correspond to each other.

In the above structure, it is preferable that the X-ray beam irradiation direction is substantially perpendicular to the sample surface. Further, in the above configuration, it is preferable that the sample observation direction is substantially perpendicular to the sample surface.

[0017]

According to the above construction, since the X-ray beam irradiation position and the sample observation position are set apart from each other by a predetermined distance, it is necessary to bring the X-ray collimator closer to the sample and to confirm the X-ray beam irradiation region. In addition, both of the requirements for bringing the sample observing means closer to the sample can be satisfied. That is, the diameter of the X-ray spot can be reduced by bringing the X-ray collimator close to the sample, and the spot intensity distribution can be formed uniformly, for example, in a rectangular shape.

Further, since the X-ray beam irradiation direction is substantially perpendicular to the sample surface, the X-ray beam that has passed through the X-ray collimator irradiates the sample with substantially the same shape, and is obliquely incident. It is possible to prevent the X-ray spot deformation due to. In addition to the fact that the sample observation direction is substantially perpendicular to the sample surface, the X-ray irradiation position and the observation position match even if the sample surface is irregular or deformed. The operations such as fine position adjustment and focus adjustment are not required, and the time required for these operations can be saved, and the X-ray analysis work of the sample can be performed quickly.

Further, since the positioning operation for matching the X-ray beam irradiation position and the observation position can be performed by adjusting the sample position by the sample conveying means, the fine adjustment mechanism of the X-ray beam position and the sample observing means can be used. It is not necessary and the alignment can be done quickly. Therefore, the alignment can be easily performed even when the X-ray beam generator or the sample observation means is replaced or repaired.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of an embodiment of the X-ray analysis apparatus of the present invention.

The sample 4 is transported and fixed to the sample observing position where the sample observing means 10 is provided by a sample transporting means such as an XY table, a conveyor belt and a robot arm. Explaining the configuration of the sample observing means 10, a lamp and an L
The illumination light emitted from the light source 11 such as an ED is the condenser lens 1
2 is collected by the beam splitter 2, reflected by the beam splitter 14 such as a half mirror, and passed through the objective lens 15 to obtain the sample 4
Illuminate the surface of. The light reflected or scattered from the sample 4 is collected again by the objective lens 15, passes through the beam splitter 14, and is once focused on the collimation plate 16 having a reticle or the like, and is then focused by the eyepiece lens 17 and the imaging lens 18. An image is formed on the image pickup device 19 such as a TV camera or a two-dimensional array sensor. The output signal of the image sensor 19 is subjected to predetermined signal processing, and the state of the sample 4 can be observed on an image monitor (not shown). It should be noted that it is possible to incorporate an automatic or manual focusing mechanism in the sample observing means 10, and instead of or in combination with the image sensor 19, a line sensor, P
SD, photographic film, etc. can be used.

The analysis operator observes the surface of the sample 4 and the collimation plate 16 on the image monitor while observing the sample surface, and an X-ray analysis region is introduced at a predetermined position of the collimation plate image. As described above, the sample transport means is controlled to position the sample. It is also possible to incorporate another photodetector or perform image processing of the combined image to automatically detect the X-ray analysis region and automatically control the sample transport means.

The relative positional relationship between the sample observation position corresponding to the predetermined position of the collimation plate image and the X-ray beam irradiation position described later is as follows.
After being measured in advance and stored as coordinate displacement data in the memory of the control unit of the sample transport means, the sample position coordinates at the time of the sample introduction operation described above are measured, and coordinate displacement data is added to or subtracted from this coordinate to obtain an X-ray. The coordinates of the beam irradiation position can be determined. Therefore, if the analysis target region of the sample is introduced at a predetermined position of the collimation plate image, the sample transport means accurately transports the distance corresponding to the coordinate displacement data (corresponding to the Y distance in FIG. 1), and 4 can be accurately positioned at the X-ray beam irradiation position. As such a high precision transfer means, (1) position control means for driving an XY table with a ball screw and a stepping motor, (2) the above
Instead of the stepping motor of (1), position control means combining a DC motor and a rotary encoder or a linear encoder, (3) position control means combining an XY table with a linear motor and a linear encoder, etc. can be used. .. These carrying means carry a predetermined distance in proportion to the number of pulses, and can be numerically controlled by a computer.

The sample 4 accurately positioned at the X-ray beam irradiation position is subjected to X-ray analysis. An X-ray beam 2 emitted from an X-ray beam generator 1 such as a rotating anticathode X-ray source or a sealed X-ray tube is irradiated onto the surface of the sample 4 in a spot shape via an X-ray collimator 3 such as a pinhole collimator. To be done.
The X-ray collimator 3 can be brought close to the sample 4 without being interfered by other device components. Therefore, X
The setting range of the line beam irradiation system is expanded, and the degree of freedom in setting the X-ray spot shape and the X-ray beam irradiation angle is increased. Generally, in order to improve the spatial resolution of sample analysis,
It is preferred that the X-ray spot shape can be set small so that the X-ray collimator 3 is brought as close as possible to the sample 4 within a range that does not interfere with X-ray detection.

The sample 4 for which analysis such as X-ray spectrum measurement has been completed is sent to a sample stacker (not shown) in the subsequent stage by the sample carrying means.

[0026]

As described above in detail, in the X-ray analyzer of the present invention, the X-ray beam irradiation position and the sample observation position are set at a predetermined distance from each other, and therefore both the X-ray collimator and the sample observation means are provided. It becomes possible to approach the sample,
By setting the X-ray spot shape small, the spatial resolution of X-ray analysis can be improved.

Further, since the X-ray beam irradiation direction is substantially perpendicular to the sample surface, it is possible to prevent the X-ray spot deformation due to oblique incidence and set the X-ray spot shape small. Further, since the sample observation direction is substantially perpendicular to the sample surface, the X-ray irradiation position and the observation position match even if the sample surface is an irregular surface.
The sample can be positioned quickly, and the efficiency of the X-ray analysis work can be improved.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of an X-ray analysis apparatus of the present invention.

FIG. 2 is a schematic configuration diagram of an example of a conventional X-ray analysis apparatus.

3A and 3B are explanatory views of an X-ray spot position and a focus position of sample observation, FIG. 3A is a cross-sectional view of a state in which the surface of the sample 4 is recessed, and FIG. 3B is a surface of the sample 4 is deformed into a convex shape. It is sectional drawing of a state.

FIG. 4 is a schematic configuration diagram of another example of a conventional X-ray analysis apparatus.

5 is an explanatory view of the arrangement of an X-ray source 8, an X-ray collimator 3 and a sample 4, FIG. 5a shows a case where the distance between the X-ray collimator 3 and the sample 4 is short, and FIG. 5b shows an X-ray collimator 3 and the sample 4. This is when the distance between and is long.

[Explanation of symbols]

 1 X-ray beam generator 2 X-ray beam 3 X-ray collimator 4 Sample 5 Detected X-ray 6 X-ray detection means 7 Signal processing device 8 X-ray source 10 Sample observation means 11 Light source 12 Condenser lens 14 Beam splitter 15 Objective lens 16 Collimation plate 17 Eyepiece 18 Imaging lens 19 Imaging element 20 Perforated mirror 30 Sample table

Claims (3)

[Claims] 1. An X-ray analysis apparatus comprising an X-ray beam irradiation unit equipped with an X-ray beam generator and an X-ray collimator, an X-ray detection unit, a sample observation unit, and a sample transportation unit. The position and the sample observation position are set apart from each other by a predetermined distance, and the sample moves by the predetermined distance,
An X-ray analysis apparatus, wherein an X-ray beam irradiation region on the sample and a sample observation region are associated with each other. 2. The X-ray analyzer according to claim 1, wherein the X-ray beam irradiation direction is substantially perpendicular to the sample surface. 3. The X-ray analyzer according to claim 1, wherein the sample observation direction is a direction substantially perpendicular to the sample surface.