JP2000074859A - Sample stage and fluorescent x-ray analyzing device using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sample stage easy to work at a low cost and capable of holding a sample in the state with little deflection by providing a ring protruding part on a part of the upper surface of the sample stage, and placing the non-analyzing surface of the sample on the protruding upper surface partially in contact therewith. SOLUTION: In order to smooth the whole upper surface 2a of a sample stage 2, for example, the whole surface is not entirely polished, but ring-like protruding parts 3A, 3B, 3C having inside diameters of prescribed diameters of a sample 1, 6 inch, 8 inch or 300 mm or less are integrally formed on a part of the upper surface 2a of the sample stage 2, and only the upper surfaces 3Aa, 3Ba, 3Ca of the protruding parts 3A, 3B, 3C are polished so as to be flush. Accordingly, since the non-analyzing surface of the sample 1 is placed on the protruding part upper surfaces 3Aa, 3Ba, 3Ca partially in contact therewith, the working is facilitated at a low cost, and a disc-like sample 1 which is a semiconductor wafer can be held in the state with little deflection.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sample table which can be processed easily, is low-cost, and can hold a disk-shaped sample such as a semiconductor wafer having a predetermined diameter with a small deflection. The present invention relates to a fluorescent X-ray analyzer.

[0002]

2. Description of the Related Art A sample is irradiated with primary X-rays from an X-ray source, and secondary X-rays generated are detected by a detector, so-called fluorescent X-ray analysis. When measuring the composition and film thickness of the formed thin film, it is desirable to use the upper surface irradiation method in which primary X-rays are irradiated from above the sample with the analysis surface of the sample as the upper surface. According to the lower surface irradiation method in which the analysis surface of the sample is placed on the lower surface and its outer edge is supported and primary X-rays are irradiated from below the sample, the sample has a diameter of, for example, 30 mm.
When the diameter of the sample is large, such as a 0 mm silicon wafer, the central portion of the sample is bent by its own weight and lower than the peripheral portion, and the height relationship between the analysis portion, the X-ray source and the detection means is different from that of the central portion of the sample. This is because there is an inconvenience that the measurement error increases due to the difference in the peripheral portion.

[0003] However, even in the case of the upper surface irradiation method, it is appropriate to put the sample in a sample holder and push up the sample from below in the sample holder with a spring to support the outer edge of the upper surface of the sample, similarly to a normal sample. Not. It is not practical to prepare a sample holder capable of loading a large-diameter sample as described above and handle it with tweezers in order to avoid contamination of the sample, and to load it with a thin, brittle silicon wafer or the like. This is because the sample may be damaged by pushing up the spring.

Therefore, a disc-shaped sample such as a semiconductor wafer is subjected to a top-side irradiation method, but a sample holder is not used, and a disc-shaped sample having a size equal to or larger than that of the sample is obtained by setting the analysis surface of the sample to the upper surface. Directly on the sample stage. here,
Since the height relationship between the analysis surface and the X-ray source and the detection means differs depending on the thickness of the sample, it is usual to provide a height adjuster below the sample stage to maintain the height relationship constant.
Further, in order to perform so-called mapping analysis for analyzing an arbitrary part in one sample, X is placed below the sample stage.
Usually, a Y table or the like is provided. However, when performing the mapping analysis, it is complicated to perform the height adjustment for each arbitrary part. Therefore, even if the sample table is horizontally moved by the XY table or the like, the height of the part to be analyzed does not change. As described above, it is desirable that the surface of the sample table on which the sample is placed is as smooth and horizontal as possible, and the horizontal movement by the XY table or the like is performed along the surface. In addition, it is desirable that the sample stage electrostatically attracts and holds the sample so that the sample does not slip on the sample stage when it moves horizontally.

[0005] Under such circumstances, a sample table on which a sample such as a semiconductor wafer is mounted is polished on the entire surface of a ceramic disk having a size equal to or larger than the sample so that the sample is electrostatically attracted. The electrodes are embedded. The reason for using ceramic is that if metal is used, the sample cannot be electrostatically adsorbed, and if the sample is contaminated with the metal, there is a problem that another sample is secondarily contaminated through a washing tank or the like. is there.

[0006]

However, polishing the entire upper surface of the sample stage causes a large processing distortion due to the polishing, which may cause the sample stage to warp. Therefore, the surface of the sample stage is sufficiently smoothed. It is difficult to process, and the cost increases. Further, embedding an electrode for electrostatically adsorbing the sample not only complicates the structure, but also causes abnormal discharge, which makes it difficult to control the adsorbing force and also increases the cost.

The present invention has been made in view of the above-mentioned conventional problems, and is capable of holding a disk-shaped sample having a predetermined diameter, such as a semiconductor wafer, with a small amount of bending, which is easy to process and low in cost. It is an object of the present invention to provide a sample stage and an X-ray fluorescence analyzer using the same.

[0008]

In order to achieve the above object, a sample stage according to claim 1 is a sample stage on which a disk-shaped sample having a predetermined diameter is placed, wherein the sample stage has an upper surface. Is provided with a convex portion, and the upper surface of the convex portion is on the same surface, and a part of the non-analytical surface of the sample is placed in contact with the upper surface of the convex portion.

According to the first aspect of the present invention, only the upper surface of the convex portion provided on a part of the upper surface of the sample stage is flush with the same surface, instead of polishing the entire surface to smooth the entire upper surface of the sample stage. The non-analytical surface of the sample is placed in contact with a part of the non-analytical surface of the sample on the upper surface of the convex portion. , And can be held with little deflection.

According to a second aspect of the present invention, in the sample stage of the first aspect, the convex portion is integrally formed on an upper surface of the sample stage,
A ring-shaped protrusion having an inner diameter smaller than the predetermined diameter.
According to the sample stage of claim 2, a ring-shaped convex portion having an inner diameter smaller than the predetermined diameter is integrally formed on a part of the upper surface of the sample stage, and only the upper surface of the convex portion is on the same surface. The same effect can be obtained as in the sample stage of the first aspect.

According to a third aspect of the present invention, there is provided the sample stage according to the second aspect, wherein the predetermined diameter is plural, and accordingly, the ring-shaped convex portion is plural. According to the sample stage of the third aspect, the same operation and effect as those of the sample stage of the first aspect can be obtained with a single sample stage for a plurality of disk-shaped samples having different predetermined diameters.

According to a fourth aspect of the present invention, in the sample stage of the first aspect, the convex portion is a plurality of holding plates whose upper surfaces are polished smoothly, and the upper surfaces are on the same surface. It is mounted on the upper surface of the sample stage. According to the sample stage of claim 4, there is no need to polish the upper surface of the sample stage, and the upper surfaces of the plurality of holding plates are polished smoothly, and the upper surface of the sample stage is positioned on the same surface. Therefore, the same operation and effect as those of the sample stage of the first aspect can be obtained.

A sample stage according to a fifth aspect of the present invention is the sample stage according to the third or fourth aspect, wherein, when the sample is placed at a predetermined position on the sample stage, the sample stage is placed near the outer edge of the sample stage. Equipped with a retractable stopper that prevents movement.
According to the sample stage of the fifth aspect, with a simple structure, it is possible to prevent the sample from sliding on the sample stage when the sample stage is horizontally moved or the like.

According to a sixth aspect of the present invention, in the sample stage of the fifth aspect, the stopper is constituted by using a leaf spring which is bent in a direction perpendicular to the upper surface of the sample stage, and the stopper correspondingly prevents movement. When the sample having a diameter larger than the diameter of the sample is placed, the leaf spring is bent by the weight of the sample and becomes the same height as the upper surface of the projection. According to the sample stage of the sixth aspect, since the stopper does not require a driving source such as a motor, the movement of the sample on the sample stage can be prevented with a simpler structure.

A sample stage according to a seventh aspect is the sample stage according to any one of the first to sixth aspects, wherein the sample having the largest diameter among the predetermined diameters is placed at a predetermined position on the sample stage. A fixed stopper is provided near the outside of the edge of the sample to prevent the sample from moving. According to the sample stage of the seventh aspect, the sample having the largest diameter among the predetermined diameters can be prevented from moving on the sample stage with a simple structure.

An X-ray fluorescence analyzer according to claim 8 is the first embodiment.
And 7) a sample table, an X-ray source for irradiating the sample mounted on the sample table with primary X-rays, detection means for detecting secondary X-rays generated from the sample, and the sample table. Moving means for relatively moving the X-ray source and the detecting means. According to the fluorescent X-ray analyzer of the eighth aspect, the same operation and effect as those of the sample stage of the first aspect are obtained, and a disk-shaped sample having a predetermined diameter can be simply and accurately analyzed.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A sample stage according to a first embodiment of the present invention will be described below with reference to the drawings. As shown in FIG.
The sample table 2 is made of anodized or ceramic-coated aluminum or ceramic and has a disk-shaped sample 1 having a predetermined diameter, for example, a semiconductor wafer 1 having a diameter of 6 inches, 8 inches or 300 mm.
A, 1B, 1C (only 1A is shown) is a disk-shaped sample stage 2 on which a projection 3 is formed on a part of the upper surface 2a of the sample stage 2.
The upper surface 3a of the convex portion 3 is on the same surface, and a part of the non-analytical surface (lower surface) of the sample 1 is placed on the upper surface 3a of the convex portion 3 in contact therewith.

More specifically, a plurality of ring-shaped protrusions 3A, 3
B and 3C are formed integrally and concentrically with the sample table 2 on the upper surface 2a of the sample table 2, and a predetermined diameter of 6 inches corresponds to a ring-shaped convex portion 3A having an inner diameter smaller than that of the sample table by, for example, about several mm. A predetermined diameter of 8 inches corresponds to a ring-shaped protrusion 3B having an inner diameter smaller than that by, for example, about several mm and the ring-shaped protrusion 3A, and a predetermined diameter of 300 mm is, for example, about several mm smaller than that. The ring-shaped protrusion 3C having a small inner diameter corresponds to the ring-shaped protrusions 3B and 3A. Each ring-shaped convex portion 3A,
The width (1/2 of the difference between the outer diameter and the inner diameter) of each of 3B and 3C is, for example, 2 mm, and the protruding height from the other portion of the upper surface 2a of the sample table 2 is, for example, 0.5 mm. Annular convex parts 3A, 3B, 3
The upper surface 3Aa, 3Ba, 3Ca of C is polished and the back surface (bottom surface) of the sample table 2 which is a surface to be attached to an XY table or the like.
For example, the parallelism tolerance is within 0.01 mm. In addition, the ring-shaped convex portion 3 is, for example, 20 mm in radius.
Many may be formed at a pitch of up to 25 mm.

As described above, according to the sample stage 2 of the first embodiment, instead of polishing the entire surface 2a of the sample stage 2 in order to make the entire surface 2a smooth, the sample stage 2 1 are integrally formed with a ring-shaped protrusion 3A, 3B, 3C having an inner diameter of 6 inches, 8 inches or 300 mm or less, and upper surfaces 3Aa, 3B of the protrusions 3A, 3B, 3C.
Only the a and 3Ca need only be polished so as to be on the same surface, and a part of the non-analytical surface of the sample 1 is placed in contact with the convex upper surfaces 3Aa, 3Ba and 3Ca, so that processing is easy. , Low cost, disk-shaped sample 1 as a semiconductor wafer
Can be held with less deflection. Moreover, one sample stage 2 has a predetermined diameter of 6 inches, 8 inches or 3 inches.
Semiconductor wafers 1A, 1B,
About 1C, the effect can be obtained. Sample 1
A part of the non-analytical surface of the sample comes into contact with the convex upper surfaces 3Aa, 3Ba, and 3Ca, but the contact area can be made sufficiently small while holding the sample 1 in a state where the deflection is small. Even so, the problem of metal contamination is small. When the sample stage 2 is made of ceramic coated aluminum or ceramic, there is no contact with metal, so there is no problem of metal contamination.

In addition, the sample stage 2 is such that the sample 1 is
In the vicinity of the outside of the edge of the sample 1 when the sample 1 is placed at a predetermined position, a stopper 4 that can move the sample 1 forward and backward is provided. Specifically, the semiconductor wafers 1A, 1A of 6 inches, 8 inches or 300 mm as a sample
B and 1C are placed so that their centers 1Ac, 1Bc and 1Cc coincide with the center 2c of the sample table 2, but when the 6-inch or 8-inch semiconductor wafers 1A and 1B are placed as such. In the vicinity of the outer sides of the edges of the wafers 1A and 1B, stoppers 4A and 4B that can move forward and backward are provided every 120 degrees in the circumferential direction, that is, three each.

FIG. 2 is a sectional view taken along the line II-II of FIG.
As shown in (a), the stopper 4B is connected to the upper surface 2 of the sample table.
leaf spring 5 that flexes in a direction perpendicular to a (including projection upper surface 3a)
It is configured using. The base 5 b of the leaf spring 5 is fixed by screws 20 along the back surface (bottom surface) of the sample table 2.
The distal end of the leaf spring 5 is bent upward in a hole 2d provided in the sample table 2 to be curved in an inverted J-shape.
a, when the wafer 1C of 300 mm from the top is not mounted, the wafer 1C of 8 inches from the convex upper surfaces 3Ba and 3Aa.
A position higher than the thickness of B (for example, 0.7 mm),
For example, it is set to be 2 mm higher. Therefore, in FIG. 1, when an 8-inch wafer 1B is placed at a predetermined position on the sample stage 2, the top 5a of the leaf spring 5 of the stopper 4B is moved radially by, for example, only 1 mm of the edge of the wafer 1B. If it is set to be located outside, movement of the wafer 1B on the sample stage 2 is prevented.

As shown in FIG. 2 (b), when a semiconductor wafer 1C of 300 mm larger than the 8-inch semiconductor wafer 1B whose stopper 4B correspondingly blocks movement is mounted, the wafer 1C The leaf spring 5 is bent by its own weight, and the top 5a becomes the same height as the convex upper surfaces 3Ca, 3Ba, 3Aa. At this time, the hole 2d is formed so that the lower portion and the front portion of the tip portion of the leaf spring 5 do not contact the sample table 2.

When a 6-inch semiconductor wafer 1A is placed at a predetermined position on the sample stage 2, the wafer 1A
A stopper 4A (FIG. 1) provided near the outside of the edge of the semiconductor wafer 1A for preventing the movement of the wafer 1A is configured similarly to the stopper 4B corresponding to the 8-inch semiconductor wafer 1B, and the stopper 4A corresponds thereto. When the 8-inch or 300-mm semiconductor wafers 1B and 1C, which are larger than the 6-inch semiconductor wafer 1A that prevents movement, are placed, the leaf springs 5 are bent by the weight of the wafers 1B and 1C, and the upper surface of the convex portion is bent. The height is the same as 3Ca, 3Ba, 3Aa.
In the above description, the leaf spring 5 is usually made of metal. However, if at least the vicinity of the top 5a of the leaf spring 5 is ceramic-coated, the problem of metal contamination due to contact between the metal and the wafer 1 can be avoided.

As described above, according to the sample stage 2 of the first embodiment, when the sample stage 2 is horizontally moved by the lower XY table with the stoppers 4A and 4B having a simple structure that does not require a driving source such as a motor. Furthermore, the semiconductor wafers 1A and 1B of 6 inches or 8 inches as a sample can be prevented from sliding on the sample table 2 and moving.

Further, as shown in FIG.
Is a semiconductor wafer 1C having a maximum diameter of 300 mm among predetermined diameters of 6 inches, 8 inches and 300 mm.
Wafer 1 when placed at a predetermined position in
In the vicinity of the outside of the edge of C, three fixed stoppers 6 for stopping the movement of the wafer 1C are provided every 120 degrees in the circumferential direction, that is, three stoppers 6 are provided. Specifically, VV in FIG.
As shown in FIG. 5 which is a cross-sectional view, the inner surface of the stopper 6 having an L-shaped cross section is brought into contact with the side surface and the bottom surface of the sample table 2 having a diameter of, for example, 302 mm, which is slightly larger than the wafer 1C. It is fixed to the table 2 with screws or the like.

The upper end of the stopper 6 is more than the thickness (for example, 1 mm) of the 300 mm wafer 1B from the upper surface 3a of the convex portion, that is, the lower surface (non-analytical surface) 1Cb of the placed 300 mm wafer 1C. The position is set to a high position, for example, a position 2 mm higher. Therefore, FIG.
In this case, when a 300 mm wafer 1C is placed at a predetermined position on the sample table 2, the upper end of the stopper 6 is located 1 mm radially outside the edge of the wafer 1C, and the sample table 2 The movement of the wafer 1C above is prevented. When the stopper 6 is made of metal, at least the inner surface of the upper portion of the stopper 6 is coated with ceramic, so that the problem of metal contamination due to contact between the metal and the wafer 1 can be avoided.

As described above, according to the sample stage 2 of the first embodiment, the 300 mm wafer 1C having the largest diameter among the predetermined diameters is moved on the sample stage 2 by the stopper 6 having a simple structure. Can be prevented.

The sample table 2 is fixed to the XY table or the like of the apparatus using the sample table 2 below with screws 21 or the like at the counterbore portions 2f formed at three places. Further, the sample stage 2 is formed with a substantially rectangular notch 2e so that the robot hand 22 for transporting the semiconductor wafers 1A, 1B, and 1C as the samples can move up and down (perpendicularly to the paper surface).

Next, a sample stage according to a second embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 3, this sample stage 12 is replaced with the ring-shaped convex portions 3A, 3B, 3C (FIG. 1) in the sample stage 2 of the first embodiment, and has respective upper surfaces 13a.
Are provided on the upper surface 12a of the sample stage 12 so that the upper surface 13a is on the same surface as the three holding plates 13 which are smoothly polished. Instead of the stoppers 4A and 4B (FIG. 1) using the plate spring 5 in the table 2, the stoppers 14A and 14B using a slider or the like are provided, and the rest is the same as the sample table 2 of the first embodiment. The description is omitted because it is the same.

Specifically, first, each upper surface 13
a holding plate 13 made of ceramic polished smoothly
Are provided at every 120 degrees in the circumferential direction, that is, three in the circumferential direction so as to be convex portions on the upper surface 12a of the sample stage 12. Here, as shown in FIG. 4 which is a cross-sectional view taken along the line IV-IV in FIG. 3, the holding plate 13 is provided in a concave portion 12g formed on the upper surface 2a of the sample stage 2.

The mounting of the holding plate 13 is performed as follows. First, a screw 23 is passed through the two through-holes 12h of the sample table 12 from below, and the tips are slightly screwed into the screw holes 13h at both ends of the holding plate 13. Then, the upper surface 1 of the holding plate 13
The two through-holes 12h are set so that the protrusion of the upper surface 13a of the holding plate 13a from the upper surface 12a of the sample table outside the recess 12g is, for example, 1 mm while applying a dial gauge or the like to the 3a.
The screw 24 is screwed into the screw hole 12i provided in the middle of the screw from below, and the amount of rotation of the screw 24 whose tip abuts on the lower surface of the holding plate 13 is adjusted. Thereafter, the holding plate 13 is fixed by tightening the two screws 23. Thereby, the three holding plates 13 are mounted on the upper surface of the sample table so that the upper surfaces are on the same surface. In FIG. 3, the portion of the holding plate 13 radially inside the sample table 12 is slightly inside the edge when a 6-inch wafer is placed, and the radial direction of the sample table 12 in the holding plate 13 is small. The outer portion is set to be slightly inside the edge of the 8-inch wafer when it is placed.

As described above, according to the sample stage 12 of the second embodiment, the upper surface 12a of the sample stage 12 does not need to be polished,
The upper surfaces 13a of the three holding plates 13 are polished smoothly, and the sample table 12 is polished so that the upper surfaces 13a are on the same surface.
And the upper surface 13a of the holding plate.
Since a part of the non-analytical surface of the sample 1 is placed in contact with the sample a, the processing is easy, the cost is low, and the disk-shaped sample 1 as a semiconductor wafer can be held in a state where the deflection is small. In addition, the operation and effect can be obtained for a plurality of semiconductor wafers 1A, 1B, and 1C having a predetermined diameter different from 6 inches, 8 inches, or 300 mm on one sample table 12. Although a part of the non-analytical surface of the sample 1 comes into contact with the upper surface 13a of the holding plate, since the holding plate 13 is made of ceramic, there is no problem of metal contamination.

The sample stage 12 of the second embodiment is provided with a 6-inch wafer 1A (FIG. 1) when the sample 1A (FIG. 1) is placed at a predetermined position on the sample stage 12. In the vicinity of the outside of the edge, a stopper 14A that can move forward and backward to prevent the movement of the wafer 1A is provided in the circumferential direction.
Stopper 14 provided at every 0 degrees, that is, three, and similarly, stops movement of 8-inch wafer 1B (not shown).
B is provided. Here, the movable stopper 14
Reference numerals A and 14B denote cylindrical members which are inserted from below into through holes provided in the sample table 12 and are advanced and retracted by a plunger or the like. When the stoppers 14A and 14B are made of metal, at least the stoppers 14A and 14B
If the upper surface and the upper portion of the side surface of 14B are ceramic-coated, the problem of metal contamination due to contact between the metal and the wafer 1 can be avoided. The advance and retreat of the stoppers 14A and 14B are appropriately performed according to the size of the wafer 1 detected by an optical sensor or the like provided above the sample table 12 or the like.

That is, when the 6-inch wafer 1A is placed, the stopper 14A has its upper end more than the thickness (for example, 0.7 mm) of the 6-inch wafer 1A from the holding plate upper surface 13a. It protrudes to a higher position, for example, a position higher by 2 mm. Therefore, when the 6-inch wafer 1A is placed at a predetermined position on the sample table 12, the upper end of the stopper 14A is set so as to be located radially outside the edge of the wafer 1A by, for example, only 1 mm. If so, the movement of the wafer 1A on the sample table 12 is prevented.

When the 8-inch wafer 1B is placed, only the stopper 14B protrudes similarly, the stopper 14A does not protrude, and the upper end thereof is
It is at a height lower than a. Therefore, when the 8-inch wafer 1B is placed at a predetermined position on the sample table 12, the upper end of the stopper 14B is set so as to be located radially outside by only 1 mm, for example, the edge of the wafer 1B. If so, the movement of the wafer 1B on the sample stage 12 is prevented. Further, when a 300 mm wafer 1C (not shown) is mounted, the stoppers 14A and 14B do not protrude, and similarly to the sample table 2 of the first embodiment, the fixed stopper 6 in FIG. Prevents the movement of the wafer 1C on the sample stage 12. In FIG. 5, in the case of the second embodiment, there is no annular convex portion 3C. As described above, according to the sample stage 12 of the second embodiment, the sample 1 slides on the sample stage 12 when the sample stage 12 is horizontally moved or the like with a simple structure without using electrostatic attraction. Can be prevented.

Next, an X-ray fluorescence analyzer according to a third embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 6, this apparatus applies the primary X-rays 7 to the sample tables 1 and 12 of the first or second embodiment and the semiconductor wafer 1 as a sample placed on the sample tables 1 and 12. An X-ray source 8 such as an X-ray tube for irradiation, detection means 10 for detecting secondary X-rays 9 generated from the sample 1, sample tables 1 and 12, the X-ray source 8 and the detection means 10 are relatively positioned. Moving means 11 for moving.
Here, the detecting means 10 includes a spectroscope that splits the secondary X-rays 9 generated from the sample 1 and a detector 26 that detects the split secondary X-rays. The moving means 11 includes an XY table 27 that fixes the sample tables 1 and 12 and moves the sample tables 1 and 12 along a horizontal plane, and a height adjuster 28 that changes the height of the XY table 27. Consists of In addition, this apparatus converts the semiconductor wafer 1 as a sample into
A robot hand (automatic transfer device) 22 (FIG. 1) for transferring the cassette into and out of the cassette is provided.

According to the apparatus of the third embodiment, as in the case of the sample tables 1 and 12 of the first or second embodiment, the semiconductor wafer 1 of a plurality of sizes, which is easy to process, is low in cost, and is a sample. , And can be held with little deflection. In addition, the simple structure prevents the semiconductor wafer from sliding on the sample tables 2 and 12 when the sample tables 2 and 12 are horizontally moved by the lower XY table. can do. Therefore, semiconductor wafers 1 of a plurality of sizes can be simply and accurately analyzed.

[0038]

As described above, according to the present invention,
Instead of polishing the entire surface of the sample table to make it smooth, the upper surface of the protrusion provided on a part of the upper surface of the sample table may be configured to be on the same surface. Since a part of the non-analytical surface of the sample is placed in contact with the upper surface of the sample, the sample can be easily processed at a low cost, and a sample such as a semiconductor wafer can be held with a small amount of deflection.

[Brief description of the drawings]

FIG. 1 is a plan view showing a sample stage according to a first embodiment of the present invention.

FIG. 2A is a cross-sectional view showing a state where a stopper capable of moving back and forth of the sample stage is advanced, and FIG. 2B is a cross-sectional view showing a state where the stopper is retracted.

FIG. 3 is a plan view showing a sample stage according to a second embodiment of the present invention.

FIG. 4 is a sectional view showing a holding plate of the sample stage.

FIG. 5 is a sectional view showing a fixed stopper of the sample stage according to the first or second embodiment of the present invention.

FIG. 6 is a plan view showing a fluorescent X-ray analyzer according to a third embodiment of the present invention.

[Explanation of symbols]

1, a disk-shaped sample having a predetermined diameter; 2, 12, a sample stage; 2a, 12a, an upper surface of the sample stage; 3, a convex portion (ring-shaped convex portion); 3a, an upper surface of a ring-shaped convex portion; , 14 ... a movable stopper, 5 ... a leaf spring, 6 ... a fixed stopper,
7: primary X-ray, 8: X-ray source, 9: secondary X-ray, 10: detecting means, 11: moving means, 13: convex part (holding plate), 13a
... the upper surface of the holding plate.

Claims (8)

[Claims] 1. A sample table on which a disk-shaped sample having a predetermined diameter is placed, wherein the sample table has a projection on a part of its upper surface, and the upper surface of the projection is on the same surface. A sample table on which a part of the non-analytical surface of the sample is placed in contact with the upper surface of the projection. 2. The sample stage according to claim 1, wherein the projection is a ring-shaped projection integrally formed on an upper surface of the sample stage and having an inner diameter smaller than the predetermined diameter. 3. The sample stage according to claim 2, wherein the predetermined diameter is plural, and the ring-shaped convex part is plural according to the predetermined diameter. 4. The method according to claim 1, wherein the projections are a plurality of holding plates whose upper surfaces are polished smoothly, and are attached to the upper surface of the sample stage such that the upper surfaces are on the same surface. Sample table. 5. The stopper according to claim 3 or 4, further comprising an advancing and retreating stopper for preventing the movement of the sample near an outer edge of the sample when the sample is placed at a predetermined position on the sample table. Equipped sample table. 6. The sample according to claim 5, wherein the stopper is formed using a leaf spring that is bent in a direction perpendicular to the upper surface of the sample table, and the stopper has a diameter larger than the diameter of the sample correspondingly preventing movement. A sample stage having the same height as the upper surface of the projection when the sample is placed and the leaf spring is bent by the weight of the sample. 7. The method according to claim 1, wherein when the sample having the largest diameter among the predetermined diameters is placed at a predetermined position on a sample stage, the sample is located near an outer edge of the sample. A sample stage with a fixed stopper that blocks sample movement. 8. A sample stage according to claim 1, an X-ray source for irradiating the sample mounted on the sample stage with primary X-rays, and a secondary X-ray generated from the sample. An X-ray fluorescence spectrometer comprising: a detecting unit for detecting; and a moving unit for relatively moving the sample stage, the X-ray source, and the detecting unit.