JP4095991B2 - Total reflection X-ray fluorescence analyzer - Google Patents

Description

  The present invention relates to a total reflection X-ray fluorescence spectrometer that performs so-called mapping measurement.

  2. Description of the Related Art Conventionally, for example, there is a total reflection fluorescent X-ray analyzer that performs mapping measurement in order to investigate the contamination status of a silicon wafer surface. As shown in FIG. 2, the movement and inclination adjustment of a sample 1 placed on a sample stage 2 Stage 18 (the portion below the upper XY stage 12 is broken and omitted), and a plurality of measurement points on the sample surface 1a have a small incident angle θ (for example, about 0.05 °). For the sake of illustration and easy understanding, the primary X-ray 3 is made incident as shown in FIG. 2 (exaggerated in FIG. 2), and the X-ray 4 totally reflected does not enter the detector 6 and escapes in the right direction of the drawing 1. The intensity of the secondary X-ray 5 such as the fluorescent X-ray 5b generated from the light is measured by the detector 6, and the distribution of the measured intensity and the distribution of the analysis value such as the amount of adhesion based on the measured intensity is automatically obtained.

  The incident angle θ needs to be an appropriate angle within a range larger than 0 degree and smaller than the critical angle of total reflection so that the S / N ratio is good in the analysis. The appropriate angle value can be determined in advance. As a known method for adjusting the angle of the stage 18 for each sample 1 and setting the incident angle θ to an appropriate angle, for example, Patent Document 1 discloses. There are a halving method, an optical displacement sensor method, a fluorescent X-ray intensity monitoring method, and the like described as conventional techniques. Here, for accurate analysis, the incident angle θ of the primary X-ray 3 should remain unchanged even when the sample 1 is moved by the XY stage 12 and the measurement point is changed. Therefore, the primary X-ray 3 is measured at each measurement point while maintaining the inclination of the sample 1 adjusted first, that is, the angle of the stage 18, because of the influence of the mechanical accuracy of the XY stage 12 and the deflection of the sample 1 itself. May change the incident angle θ.

Therefore, for example, in the apparatus described as an embodiment in Patent Document 1, the incident angle of the primary X-ray is made appropriate by using the optical displacement sensor method as it is or with the center portion of the sample surface as a reference. In addition to adjusting the stage angle, the measurement intensity of fluorescent X-rays that are uniformly generated from the sample surface and serve as a reference (for example, Si-Kα ray generated from the silicon wafer surface) is stored as the reference intensity, and each measurement point is stored. The stage angle is adjusted so that the measurement intensity of the fluorescent X-ray as the reference matches the reference intensity.
Japanese Patent No. 2978460 (paragraphs 0003-0007, 0026-0032, 0034-0036)

  However, in recent years, it has been desired to designate a large number of measurement points for detailed mapping measurement on a large-diameter wafer or the like, whereas in this conventional apparatus, the reference fluorescent X-rays are measured at all measurement points. Since the intensity is measured and the stage angle is adjusted so that it matches the reference intensity, it takes a long time to obtain the distribution of the measured intensity. For example, in a wafer having a diameter of 300 mm in which 290 measurement points are designated, it takes about 2 hours to 2 hours and 40 minutes to measure one sheet. However, although the measurement time can be shortened without maintaining the stage angle at each measurement point, as described above, the incident angle of the primary X-ray may change for each measurement point. Insufficiently accurate analysis.

  The present invention has been made in view of the above-described conventional problems, and an object of the present invention is to provide a total reflection X-ray fluorescence spectrometer that performs mapping measurement and that can obtain a sufficiently accurate measurement intensity distribution in a short time. .

  In order to achieve the above object, the first configuration of the present invention includes a stage capable of moving and tilting a sample, and makes primary X-rays incident on a plurality of measurement points on the sample surface at a minute incident angle. The total reflection X-ray fluorescence analyzer that measures the intensity of the generated fluorescent X-rays and obtains the distribution of the measured intensity includes the following control means.

  The control means firstly, for a reference sample, primary X-rays at a stage position (corresponding to a reference point serving as a reference on the sample surface) based on the intensity of the reference X-ray generated uniformly from the sample surface. The stage angle is adjusted so that the incident angle is appropriate and measured as a reference intensity, and the stage angle is adjusted so that the measurement intensity of the reference X-ray matches the reference intensity at the stage position corresponding to each measurement point. And stored as a correction stage angle.

  Next, the reference intensity is measured for the sample to be analyzed. Then, by adjusting the correction stage angle at the stage position corresponding to each measurement point and measuring the intensity of the reference X-ray, when the measurement intensity of the reference X-ray matches the reference intensity The fluorescence X-ray intensity measured at the correction stage angle is used as the measurement intensity. If it does not match, the X-ray fluorescence intensity measured by adjusting the stage angle to match is used as the measurement intensity. Then, the distribution of the measured intensity is obtained and the correction stage angle is updated based on the stage angle before and after the latest adjustment.

  The inventor of the present application, when performing a mapping measurement of a group of samples having approximate dimensions and the like with the same apparatus, is appropriate at the stage position corresponding to each measurement point with respect to an appropriate stage angle at the reference stage position. As a result, the present inventors have found that the deviation of the stage angle can be approximated.

  That is, in the first configuration apparatus, an appropriate stage angle is stored as a correction stage angle for each measurement point for the reference sample, and new appropriate stage angles are obtained for all the measurement points for the analysis target sample. First, adjust the correction stage angle stored in correspondence with the measurement point, and compare the reference X-ray intensity in that state with the reference intensity at the reference point to adjust the correction stage angle. Only when it is determined that this is not appropriate, the stage angle is adjusted again to an appropriate stage angle, so that the entire measurement point can be adjusted to an appropriate stage angle in a short time. Therefore, a sufficiently accurate distribution of measured intensity can be obtained in a short time.

  In addition, since the correction stage angle is updated based on the stage angle before and after the latest adjustment, if there are variations in the deflection of the reference sample and the sample to be analyzed, the stage for the first few samples to be analyzed Since the measurement points for which the angle is readjusted are considerably generated, the measurement time is increased accordingly, but the correction stage angle is updated to a value obtained by averaging the variation, and the subsequent analysis target sample is measured at each measurement point. The correction stage angle becomes closer to the appropriate stage angle, and the frequency of readjusting the stage angle is also reduced. Therefore, it is possible to obtain a more accurate distribution of measured intensity in a shorter time for a large number of samples to be analyzed.

  The second configuration of the present invention is provided with a stage capable of moving and tilting the sample, and the intensity of fluorescent X-rays generated by causing primary X-rays to enter a plurality of measurement points on the sample surface at a minute incident angle. The total reflection X-ray fluorescence analyzer that measures the above and obtains the distribution of the measured intensity includes the following control means.

  The control means first adjusts the stage angle of the reference sample so that the incident angle of the primary X-ray becomes appropriate at the stage position based on the intensity of the reference X-ray generated uniformly from the sample surface. The intensity is measured, and the stage angle is adjusted so that the measurement intensity of the reference X-ray matches the reference intensity at the stage position corresponding to each measurement point, and stored as a correction stage angle.

  Next, the reference intensity is measured for the sample to be analyzed. Then, the intensity of the fluorescent X-ray and the reference X-ray is measured by adjusting the correction stage angle at the stage position corresponding to each measurement point, and divided by the ratio of the measured intensity of the reference X-ray to the reference intensity. Thus, the measured intensity of the fluorescent X-ray is corrected, and the corrected distribution of the measured intensity is obtained.

  In the apparatus of the first configuration, it is determined whether or not it is appropriate to adjust the correction stage angle at each measurement point, and if it is determined that it is not appropriate, the stage angle is adjusted again. On the other hand, in the apparatus of the second configuration, if the incident angle of the primary X-ray is close to an appropriate angle, the intensity of the secondary X-ray generated from the same point on the sample surface is the incident angle at any wavelength. The measured intensity of the fluorescent X-ray is compared with the reference point with respect to the measured intensity of the reference X-ray while adjusting the correction stage angle at each measurement point based on the fact that the measured intensity of the fluorescent X-ray is the primary X-ray. The intensity is corrected when the incident angle is appropriate.

  In other words, the stage angle is not further adjusted from the correction stage angle at each measurement point, and the measurement time is further shortened compared to the first configuration apparatus, and the measurement intensity of fluorescent X-rays is corrected by calculation. Thus, an effect similar to that of adjusting to an appropriate stage angle can be obtained. Therefore, a sufficiently accurate distribution of measured intensity can be obtained in a short time even by the apparatus having the second configuration.

  The third configuration of the present invention is provided with a stage capable of moving and tilting the sample, and the intensity of fluorescent X-rays generated by causing primary X-rays to enter a plurality of measurement points on the sample surface at a minute incident angle. The total reflection X-ray fluorescence analyzer that measures the above and obtains the distribution of the measured intensity includes the following control means.

  The control means first adjusts the stage angle of the reference sample so that the incident angle of the primary X-ray becomes appropriate at the stage position based on the intensity of the reference X-ray generated uniformly from the sample surface. The intensity is measured, and the stage angle is adjusted so that the measurement intensity of the reference X-ray matches the reference intensity at the stage position corresponding to each measurement point, and stored as a correction stage angle.

  Next, the analysis target sample is adjusted to the correction stage angle at the stage position corresponding to each measurement point, the intensity of the fluorescent X-ray is measured, and the distribution of the measurement intensity is obtained.

  In the apparatus of the third configuration, the measurement intensity of fluorescent X-rays is not corrected while adjusting the correction stage angle at each measurement point. That is, since the reference intensity is not measured for each sample to be analyzed, the measurement time is correspondingly shorter than that of the second configuration apparatus, and the accuracy of the measurement intensity of the fluorescent X-ray is corrected. There is no big difference. Therefore, a sufficiently accurate distribution of measured intensity can be obtained in a short time even by the apparatus of the third configuration.

  In the apparatus having the first to third configurations, the reference X-ray intensity is measured as the reference intensity for the reference sample with the stage angle adjusted so that the incident angle of the primary X-ray is appropriate at the reference stage position. In addition, at the stage position corresponding to each measurement point, the incident angle of the primary X-ray is made appropriate by adjusting the stage angle so that the measurement intensity of the reference X-ray matches the reference intensity. The stage angle is stored as a correction stage angle. However, in the present invention, the control means is not limited to such an operation when the correction stage angle is stored at the stage position corresponding to each measurement point of the reference sample.

  Accordingly, in the apparatus having the first to third configurations, the operation when the control unit stores the correction stage angle at the stage position corresponding to each measurement point of the reference sample is “the stage position corresponding to each measurement point for the reference sample”. Then, the stage angle is adjusted so that the incident angle of the primary X-ray becomes appropriate and stored as a corrected stage angle, and the device expanded and replaced with “is the apparatus of the fourth to sixth configurations of the present invention. That is, in the apparatus having the fourth to sixth configurations, the operation of adjusting the stage angle so that the control unit has an appropriate incident angle of the primary X-ray at the stage position corresponding to each measurement point of the reference sample is not particularly limited. The above-described known half-split method, optical displacement sensor method, fluorescent X-ray intensity monitoring method, and the like can also be applied. According to the devices having the fourth to sixth configurations, the same effects as those of the devices having the first to third configurations can be obtained.

  In the apparatus having the first to sixth configurations, when a non-reference measurement point that does not match a corresponding stage position with the measurement point of the reference sample is designated as the measurement point of the analysis target sample, the control means As the correction stage angle of the non-reference measurement point, a stage angle interpolated based on the correction stage angle of the measurement point where the stage position corresponding to the measurement point of the reference sample matches in the vicinity of the non-reference measurement point is used. Is preferred.

  According to this preferred configuration, it is only necessary to obtain and store the correction stage angle using the reference sample for only a part of the measurement points specified in the analysis target sample that are appropriately distributed. Thus, an effect similar to that obtained by storing and storing the correction stage angle for all the measurement points of the sample to be analyzed can be obtained.

  The total reflection X-ray fluorescence spectrometer according to the first embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, this apparatus includes a stage 18 capable of moving and adjusting the inclination of samples 1 and 9 placed on a sample stage 2, and from an X-ray source 17 such as an X-ray tube to a sample surface 1a, The primary X-rays 3 are incident on the plurality of measurement points 32 (FIG. 3) 9a at a minute incident angle θ (FIG. 2) of about 0.05 degrees, for example, and the fluorescent X-rays 5b generated from the sample 1 etc. This is a total reflection X-ray fluorescence analyzer that measures the intensity of the secondary X-ray 5 with a detector 6 such as SSD and obtains the distribution of the measured intensity and the distribution of the analysis value such as the amount of adhesion based on the measured intensity.

  Samples 1 and 9 are usually a plurality of analysis target samples 1 and a single reference sample for adjusting the stage angle at each measurement point of the analysis target sample 1 and correcting the measurement intensity of fluorescent X-rays. In this embodiment, the analysis target sample 1 and the reference sample 9 are the same type and have the same size and shape. For example, as shown in FIG. 3, if the reference sample 9 is a silicon wafer, the analysis target sample 1 to be analyzed using the silicon wafer is the presence or absence of a film (an oxide film or an attached film), and if there is a film. It is the same silicon wafer in the component and thickness (same type), and the same in the diameter and thickness, the presence or absence of orientation flats 1b and 9b, notches, etc. (matching of dimensions and shape). However, the present invention is applied to the case where the sample 1 to be analyzed is different from the reference sample 9 or when the dimensions are the same and the dimensions are small. Obtainable. In addition, as the analysis target sample 1 and the reference sample 9, rectangular ones such as a liquid crystal panel are also conceivable.

  As will be described later, the samples 1 and 9 can be moved by the XY stage 12 (FIG. 1) in the stage 18 to irradiate the primary X-ray 3 to any position (measurement point 32) on the sample surfaces 1a and 9a. However, there is a stage position serving as a reference (origin) for the movement, and the stage position corresponds to a reference point 31 serving as a reference on the sample surfaces 1a and 9a.

  Although the reference point 31 is single and there are usually a plurality of measurement points 32, the sample 1 to be analyzed has the same positions of the reference point 31 and the measurement point 32 as the reference sample 9, and the samples 1 and 9 are wafers. In this case, normally, the reference points 31 are positioned on the stage 18 via the sample stage 2 so that the positions of the reference points 31 are the centers of the sample surfaces 1a and 9a that can be regarded as circular if the orientation flats 1b and 9b and the notches are ignored. (See FIG. 1), with the reference point 31 as the origin, the measurement points 32 are set, for example, at equal intervals in the X direction and the Y direction (only one measurement point 32A in the vicinity of the reference point 31 is labeled). Is written). Here, the direction orthogonal to the orientation flats 1b and 9b is defined as the Y direction. Normally, the reference point 31 is also included in the measurement point 32. However, depending on the embodiment, the reference point 31 may not be required in the analysis target sample 1 or the measurement point 32 may not coincide with the reference sample 9 at all. is there. Moreover, although the reference sample 9 can be handled as the analysis target sample 1, the reference sample 9 may be unnecessary depending on the embodiment.

  As shown in FIG. 1, the stage 18 includes the following XY stage 12, height adjusting means 13, and swivel stage 14. First, the sample stage 2 is fixed to the upper part 12a of the XY stage (parallel moving means) 12 below the sample stage 2. The XY stage upper part 12a is installed so as to be movable in the direction Y perpendicular to the paper surface with respect to the middle part 12b, and the XY stage middle part 12b moves in the horizontal direction X on the paper surface in the state of FIG. It is installed freely. The XY stage lower part 12c is fixed to the upper part 13a of the height adjusting means 13 below the XY stage. That is, by adjusting the XY stage 12, the sample stage 2 can be moved so as to irradiate the primary X-ray 3 to any position on the sample surfaces 1a and 9a.

  The upper portion 13a of the height adjusting means 13 is installed so as to be movable in the direction of the axis Z in the state of FIG. 1 with respect to the lower portion 13b, and the lower portion 13b is the upper portion 14a of the incident angle adjusting means 14 such as a swivel stage below it. It is fixed to. That is, the height adjustment means 13 can adjust the height of the sample surface 1a with respect to the primary X-ray 3.

  The upper part 14a of the swivel stage is installed so as to be movable along an arc centered on the measurement parts of the sample surfaces 1a and 9a with respect to the lower part 14b, and the lower part 14b is fixed to the floor below. That is, the angle of inclination of the stage 18, that is, the stage angle can be adjusted by the swivel stage 14, and the incident angle θ (FIG. 2) of the primary X-ray 3 on the sample surfaces 1a and 9a can be changed.

  The incident angle adjusting means is not limited to the swivel stage 14 and may be any mechanism that changes the inclination angle of the sample table 2 with respect to the primary X-ray 3. The end of the long plate on which the sample table 2 is placed is pushed up with a jack. Such a structure may be used. When the so-called optical displacement sensor method is applied to adjust the stage angle, a displacement sensor is provided on the right side of the detector 6, and the sample is placed between the swivel stage 14 and the floor below the detector 6 and the displacement sensor. Horizontal moving means for moving the stage 2 and the stage 18 are interposed.

  The apparatus of the first embodiment includes a computer that functions as the following control means 24A according to a program. First, the control means 24A, for the reference sample 9 which is a silicon wafer, for example, sets the stage position (reference point of the sample surface 9a) based on the intensity of the Si-Kα line which is the reference X-ray 5a uniformly generated from the sample surface 9a. 31 (corresponding to FIG. 3)), the stage angle is adjusted so that the incident angle θ (FIG. 2) of the primary X-ray 3 is appropriate, and the reference intensity is measured. Then, in order to match the measured intensity of the reference X-ray 5a at the stage position corresponding to each measurement point 32A,... (FIG. 3), specifically, a predetermined range compared to the reference intensity. The stage angle is adjusted so as to be within the range and stored as a corrected stage angle.

The correction stage angle φ _m is an angle by which, for example, the φ axis for inclining the upper portion 14a of the swivel stage 14 is rotated by a motor from the horizontal state of the upper portion 14a, for example, as described above, the machine of the XY stage 12 Since there is an influence of the accuracy and the deflection of the sample 1 itself, it is deviated from the desired incident angle θ. Therefore, the correction stage angle φ _m itself at each measurement point may be stored, but here, the deviation compared to the incident angle θ at each measurement point is calculated as a correction table value as in the following equation (1). as phi _table, stored in a table.

φ _m = θ−φ _table (1)

  In order to adjust the stage angle so that the incident angle θ (FIG. 2) of the primary X-ray 3 becomes appropriate at the reference point 31 (FIG. 3), the above-described known optical displacement sensor method or the like can be applied. As described in paragraph 0013 of Patent Document 1, it is preferable to apply a method obtained by improving the optical displacement sensor method. That is, the amount of change in the inclination of the central portion of the sample table 2 (corresponding to the reference point 31 of the samples 1 and 9) below the displacement sensor and below the detector 6 is obtained in advance, and the amount of change is negated. It is preferable to adjust the stage angle by tilting the stage. Further, the reference X-ray 5a uniformly generated from the sample surface 9a is not limited to the fluorescent X-ray from the element uniformly distributed on the substrate, but from the fluorescent X-ray from the element uniformly distributed on the film or from the sample surface. Uniformly generated scattered radiation can also be used.

  Furthermore, the operation in which the control means 24 adjusts the stage angle so that the incident angle θ (FIG. 2) of the primary X-ray 3 is appropriate at each measurement point 32A of the reference sample 9 (FIG. 3) is particularly limited. Not. For example, the above-described known halving method, optical displacement sensor method, fluorescent X-ray intensity monitoring method, and the like may be applied to all measurement points 32A of the reference sample 9 (FIG. 3). Including this point, the operation until the control means 24 stores the correction stage angle at each of the measurement points 32A,... (FIG. 3) for the reference sample 9 is the same in the apparatuses of the second and third embodiments described later. .

  Next, the control means 24A measures the reference intensity for the analysis target sample 1. That is, for the sample 1 to be analyzed, similarly to the reference sample 9, the stage position (which corresponds to the reference point 31 (FIG. 3) on the sample surface 1a) based on the intensity of the Si-Kα ray that is the reference X-ray 5a. Then, the stage angle is adjusted so that the incident angle θ (FIG. 2) of the primary X-ray 3 is appropriate, and the reference intensity is measured.

Then, each measurement point 32A, ... are adjusted to correct stage angle phi _m in accordance with the table in stage position corresponding to (3), the intensity of the reference X-ray 5a is measured, the reference X-ray 5a If the measured intensity is consistent with the reference intensity, the adopted the intensity of the fluorescent X-ray 5b measured in the correction stage angle phi _m as measured intensities, if not matched, the stage Consistently The intensity of the fluorescent X-ray 5b measured by adjusting the angle is adopted as the measurement intensity.

Specifically, the procedure is as follows. First, each measurement point 32A, ... (FIG. 3) in calculates the correction stage angle phi _m from the correction table value phi _table reads the table is adjusted to the angle phi _m, the detector 6 is a SSD, the reference The intensity of the X-ray 5a and the intensity of one or more fluorescent X-rays 5b to be analyzed are simultaneously measured. And that when the measured intensity of the reference X-ray 5a is compared with the reference intensity is within a predetermined range, the correction stage angle φ of the fluorescent X-ray 5b measured in _m intensity of the fluorescent X-ray 5b Adopted as measurement intensity, if it is outside the predetermined range, the stage angle is finely adjusted until the intensity falls within the predetermined range, and the measurement of the intensity of the reference X-ray 5a and the intensity of the fluorescent X-ray 5b is repeated. . The original correction stage angle before repeating fine adjustment is φ _{m (OLD),} and the stage angle when it is within a predetermined range is φ _{m (NEW)} .

Finally, the control means 24A obtains the distribution of the measured intensity of the fluorescent X-rays 5b thus obtained on the sample surface 1a, and consequently the distribution of the analytical value such as the amount of adhesion based on the measured intensity on the sample surface 1a. The correction stage angle φ _m is updated based on the stage angles φ _{m (OLD)} and φ _{m (NEW)} before and after the latest adjustment.

Specifically, the table of the correction table value φ _table is updated. This update indicates that the measurement intensity of the reference X-ray 5a is out of a predetermined range for each sample 1 to be analyzed compared to the reference intensity. If there is at least one measurement point 32, the measurement is performed. The correction value Δφ used for updating is expressed by the following equation (2).

Δφ = φ _{m (NEW)} −φ _{m (OLD)} (2)

Using this correction value Δφ and the correction table value φ _{table (N)} before update (table update count N), the correction table value φ _{table (} N + 1) after update (table update count _{N + 1)} is given by 3). The correction table value φ _{table (N)} before the update is weighted by the number N of updates so far.

φ _{table (N + 1)} = (Δφ + φ _{table (N)} × N) ÷ (N + 1) (3)

  That is, the table stored by the control unit 24A is configured by the number of times the table is updated and the correction table value of each updated measurement point.

  As described above, when mapping a group of samples with approximate dimensions and the like using the same apparatus, the stage position corresponding to each measurement point with respect to an appropriate stage angle at the reference stage position is used. It has been found that the appropriate stage angle deviation is approximated.

Based on this, in the apparatus of the first embodiment, an appropriate stage angle is stored as the correction stage angle φ _m for each measurement point 32 for the reference sample 9, and all the measurement points for the analysis target sample 1 are stored. rather than adjusting newly seeking appropriate stage angle 32, first measurement point 32 in correspondence to adjust to the correction stage angle phi _m stored, a reference point the intensity of the reference X-ray 5a in that state Only when it is determined that it is not appropriate to adjust to the correction stage angle φ _m as compared with the reference intensity at 31, the stage is adjusted to an appropriate stage angle again. Can be adjusted in a short time. Therefore, a sufficiently accurate distribution of measured intensity can be obtained in a short time.

In addition, since the correction stage angle φ _m is updated based on the stage angles φ _{m (OLD)} and φ _{m (NEW)} before and after the latest adjustment, the deflection of the reference sample 9 and the sample 1 to be analyzed seems to vary. In this case, for the first few samples 1 to be analyzed, the measurement point 32 for adjusting the stage angle is considerably generated, so that the measurement time becomes longer, but the correction stage angle φ _m averages the variation. is updated to the value, for subsequent analysis sample 1, at each measurement point 32, the closer the correction stage angle phi _m is the appropriate stage angle also reduces the frequency of re-adjusting the stage angle. Therefore, a more accurate distribution of measured intensity can be obtained in a shorter time for a large number of samples 1 to be analyzed.

  Next, a total reflection X-ray fluorescence spectrometer according to the second embodiment of the present invention will be described. This device is different from the device of the first embodiment as described below only in part of the operation of the control means 24B, but the other points are the same and will not be described.

Control means 24B of the device of the second embodiment, like the control unit 24A of the apparatus of the first embodiment, it is stored seeking compensation stage angle phi _m using a reference sample 9, the analysis sample 1 Measure the reference strength for. Then, by adjusting the correction stage angle phi _m in stage position corresponding to each measurement point 32, to measure the intensity of the fluorescent X-ray 5b and reference X-ray 5a, the reference intensity of the measured intensity of the reference X-ray 5a The measured intensity of the fluorescent X-ray 5b is corrected by dividing by the ratio to ## EQU3 ## and the corrected distribution of measured intensity is obtained.

In the apparatus of the first embodiment, it is determined whether or not it is appropriate to adjust the correction stage angle φ _m at each measurement point 32, and the stage angle is adjusted again when it is determined that it is not appropriate. On the other hand, in the apparatus of the second embodiment, if the incident angle θ of the primary X-ray 3 is in the vicinity of an appropriate angle, the intensity of the secondary X-ray 5 generated from the same point on the sample surfaces 1a and 9a is based on that a substantially proportional relationship between even the incident angle θ for any wavelength, remain adjusted to the correction stage angle phi _m at each measurement point 32, to be compared with the reference point 31 for measuring the intensity of the reference X-ray 5a Thus, the measured intensity of the fluorescent X-ray 5b is corrected to the intensity when the incident angle θ of the primary X-ray 3 is appropriate.

In other words, the stage angle is not further adjusted from the correction stage angle φ _{m at} each measurement point 32, and the measurement time is further shortened as compared with the apparatus of the first embodiment, and the measurement intensity of the fluorescent X-ray 5b is increased. By correcting by calculation, an effect similar to adjusting to an appropriate stage angle can be obtained. Therefore, even with the apparatus of the second embodiment, a sufficiently accurate distribution of measured intensity can be obtained in a short time.

  Next, a total reflection X-ray fluorescence spectrometer according to a third embodiment of the present invention will be described. This device is different from the device of the second embodiment as described below only in part of the operation of the control means 24C, but the other points are the same, and the description is omitted.

Control means 24C of the apparatus of the third embodiment, similarly to the control unit 24B of the apparatus of the second embodiment, stores seeking compensation stage angle phi _m using a reference sample 9. Next, the sample 1 to be analyzed is adjusted to the correction stage angle φ _m at the stage position corresponding to each measurement point 32, the intensity of the fluorescent X-ray 5b is measured, and the distribution of the measured intensity is obtained.

In the device of the third embodiment, while adjusting the correction stage angle phi _m at each measurement point 32, nor to correct the measured intensity of the fluorescent X-ray 5b. That is, since the reference intensity is not measured for each sample 1 to be analyzed, the measurement time is correspondingly shorter than that of the apparatus of the second embodiment, and the accuracy of the measurement intensity of the fluorescent X-ray 5b is corrected. There is no significant difference compared to the apparatus of the embodiment. Therefore, even with the apparatus of the third embodiment, a sufficiently accurate distribution of measured intensity can be obtained in a short time.

In the apparatus of the first to third embodiments, as the measurement points 32 and 33 of the sample 1 to be analyzed shown in FIG. 4 (only the measurement points 32A and 33A in the vicinity of the reference point 31 are indicated by symbols), respectively. When the non-reference measurement point 33 whose position (corresponding stage position) does not match the measurement point 32 of the reference sample 9 shown in FIG. 3 is designated, the control means 24A, 24B, 24C As the correction stage angle 33, the stage angle interpolated based on the correction stage angle φ _m of the measurement point 32 whose position (corresponding stage position) coincides with the measurement point 32 of the reference sample 9 in the vicinity of the non-reference measurement point 33. it is preferable to use a phi _m.

For example, when the reference point 31 is included in the measurement point 32, a measurement point 32 whose position (corresponding stage position) matches the measurement point 32 of the reference sample 9 in the vicinity of the non-reference measurement point 33A in FIG. Since there is a measurement point 31 and a measurement point 32A, and the non-reference measurement point 33A is located exactly in the middle between both measurement points 31, 32A, the correction stage angle φ _{m (33A)} of the non-reference measurement point 33A is defined as the measurement point 31A. The average (φ _{m (31)} + φ _{m (32A)} ) / 2 of the correction stage angle φ _{m (31)} and the correction stage angle φ _{m (32A) at} the measurement point 32A can be used.

According to this preferred configuration, the correction stage angle φ _m is obtained and stored using the reference sample 9 only for a part 32 appropriately distributed among the measurement points 32 and 33 specified by the analysis target sample 1. Therefore, it is possible to simply obtain an effect that approximates that of obtaining and storing the correction stage angle φ _m for all the measurement points 32 and 33 of the sample 1 to be analyzed.

  Next, a total reflection X-ray fluorescence spectrometer according to the fourth embodiment of the present invention will be described. This device is different from the device of the second embodiment in the operation of the control means 24D as follows, but the other points are the same and the description is omitted.

  The control means 24D of the apparatus of the fourth embodiment, for the sample 1 to be analyzed, is a stage position based on the intensity of the reference X-ray 5a that is uniformly generated from the sample surface 1a (corresponding to the reference point 31 on the sample surface 1a). Then, the stage angle is adjusted so that the incident angle θ of the primary X-ray 3 is appropriate, and the reference intensity is measured. Then, maintaining the adjusted stage angle, the intensity of the fluorescent X-ray 5b and the reference X-ray 5a is measured at the stage position corresponding to each measurement point 32, and the measured intensity of the reference X-ray 5a with respect to the reference intensity By dividing by the ratio, the measured intensity of the fluorescent X-ray 5b is corrected, and the corrected distribution of the measured intensity is obtained.

  The apparatus of the fourth embodiment is a simplification of the apparatus of the second embodiment, and does not use the correction stage angle, but instead is appropriate when the reference intensity is measured at the reference point 31 of each analysis target sample 1. A suitable stage angle is used at each measurement point 32. That is, while maintaining the stage angle, the measurement stage 32 is not adjusted to the correction stage angle, and the measurement time is further shortened compared with the apparatus of the second embodiment. Although the degree of correction of the measurement intensity of the fluorescent X-ray 5a is slightly increased, an effect similar to that of adjusting to an appropriate stage angle can be obtained. Therefore, even with the apparatus of the fourth embodiment, a sufficiently accurate distribution of measured intensity can be obtained in a short time.

  Next, a total reflection X-ray fluorescence spectrometer according to a fifth embodiment of the present invention will be described. This device is different from the device of the fourth embodiment in the operation of the control means 24E as follows, but the other points are the same and the description is omitted.

  First, the control means 24E of the apparatus of the fifth embodiment, for the reference sample 9, corresponds to the stage position (reference point 31 of the sample surface 9a) based on the intensity of the reference X-ray 5a uniformly generated from the sample surface 9a. ), The stage angle is adjusted so that the incident angle θ of the primary X-ray 3 is appropriate, and the reference intensity is measured. Next, with respect to the sample 1 to be analyzed, the stage angle adjusted with the reference sample 9 is maintained, and the intensities of the fluorescent X-ray 5b and the reference X-ray 5a are measured at the stage position corresponding to each measurement point 32. The measured intensity of the fluorescent X-ray 5b is corrected by dividing the measured intensity of the X-ray 5a by the ratio of the reference intensity to obtain the distribution of the measured intensity after correction.

  The apparatus of the fifth embodiment is a further simplification of the apparatus of the fourth embodiment, and does not measure the reference intensity by appropriately adjusting the stage angle at the reference point 31 for each sample 1 to be analyzed. Instead, the stage angle appropriately adjusted at the reference point 31 of the reference sample 9 and the measured reference intensity are used. That is, the stage angle adjusted at the reference point 31 of the reference sample 9 is maintained, and the stage angle is not adjusted at the reference point 31 of each analysis target sample 1, and the measurement time correspondingly is the same as that of the fourth embodiment. In addition to being shorter than the apparatus, the degree of correction of the measurement intensity of the fluorescent X-rays 5b at each measurement point 32 is slightly larger, but an effect similar to adjusting to an appropriate stage angle is obtained. Therefore, even with the apparatus of the fifth embodiment, a sufficiently accurate distribution of measured intensity can be obtained in a short time.

It is the schematic which shows the total reflection X-ray fluorescence analyzer of the 1st-5th embodiment of this invention. It is a figure explaining the principle of a total reflection fluorescence X ray analysis. It is a figure which shows an example of a reference | standard sample and an analysis object sample. It is a figure which shows another example of a sample to be analyzed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Analysis object sample 1a Analysis object sample surface 3 Primary X-ray 5a Reference X-ray 5b Fluorescence X-ray 9 Reference sample 9a Reference sample surface 18 Stage 24 Control means 31 Reference point 32 Measurement point 33 Non-reference measurement point θ To sample Primary X-ray incident angle φ _m Correction stage angle

Claims (7)

A stage capable of moving and tilting the sample is provided. Primary X-rays are incident on a plurality of measurement points on the sample surface at a minute incident angle to measure the intensity of the generated fluorescent X-rays, and the distribution of the measured intensity In the total reflection X-ray fluorescence analyzer for obtaining
For the reference sample, the intensity of the reference X-ray generated uniformly from the surface of the sample is measured as the reference intensity by adjusting the stage angle so that the incident angle of the primary X-ray is appropriate at the reference stage position. Adjusting the stage angle so that the measured intensity of the reference X-ray matches the reference intensity at the stage position corresponding to the point, and storing it as a corrected stage angle;
For the sample to be analyzed, measure the reference intensity,
Adjust to the correction stage angle at the stage position corresponding to each measurement point, measure the intensity of the reference X-ray,
When the measurement intensity of the reference X-ray matches the reference intensity, the intensity of the fluorescent X-ray measured at the correction stage angle is adopted as the measurement intensity, and when it does not match, it matches. The intensity of fluorescent X-rays measured by adjusting the stage angle is adopted as the measurement intensity.
A total reflection X-ray fluorescence analysis apparatus comprising a control means for obtaining a distribution of measurement intensity and updating the correction stage angle based on a stage angle before and after the latest adjustment. A stage capable of moving and tilting the sample is provided. Primary X-rays are incident on a plurality of measurement points on the sample surface at a minute incident angle to measure the intensity of the generated fluorescent X-rays, and the distribution of the measured intensity In the total reflection X-ray fluorescence analyzer for obtaining
For the reference sample, the intensity of the reference X-ray generated uniformly from the surface of the sample is measured as the reference intensity by adjusting the stage angle so that the incident angle of the primary X-ray is appropriate at the reference stage position. Adjusting the stage angle so that the measured intensity of the reference X-ray matches the reference intensity at the stage position corresponding to the point, and storing it as a corrected stage angle;
For the sample to be analyzed, measure the reference intensity,
Adjust the correction stage angle at the stage position corresponding to each measurement point, measure the intensity of the fluorescent X-ray and the reference X-ray, and divide by the ratio of the measurement intensity of the reference X-ray to the reference intensity A total reflection X-ray fluorescence analysis apparatus comprising a control means for correcting the measurement intensity of fluorescent X-rays to obtain a distribution of the measured intensity after correction. A stage capable of moving and tilting the sample is provided. Primary X-rays are incident on a plurality of measurement points on the sample surface at a minute incident angle to measure the intensity of the generated fluorescent X-rays, and the distribution of the measured intensity In the total reflection X-ray fluorescence analyzer for obtaining
For the reference sample, the intensity of the reference X-ray generated uniformly from the surface of the sample is measured as the reference intensity by adjusting the stage angle so that the incident angle of the primary X-ray is appropriate at the reference stage position. Adjusting the stage angle so that the measured intensity of the reference X-ray matches the reference intensity at the stage position corresponding to the point, and storing it as a corrected stage angle;
All of the samples to be analyzed are provided with control means for adjusting the correction stage angle at the stage position corresponding to each measurement point, measuring the intensity of the fluorescent X-rays, and obtaining the distribution of the measurement intensity. Reflective fluorescent X-ray analyzer. A stage capable of moving and tilting the sample is provided. Primary X-rays are incident on a plurality of measurement points on the sample surface at a minute incident angle to measure the intensity of the generated fluorescent X-rays, and the distribution of the measured intensity In the total reflection X-ray fluorescence analyzer for obtaining
For the reference sample, adjust the stage angle so that the incident angle of the primary X-ray is appropriate at the stage position corresponding to each measurement point, and store it as a corrected stage angle.
For the sample to be analyzed, the intensity of the reference X-ray generated uniformly from the surface of the sample is measured as the reference intensity by adjusting the stage angle so that the incident angle of the primary X-ray is appropriate at the reference stage position,
Adjust to the correction stage angle at the stage position corresponding to each measurement point, measure the intensity of the reference X-ray,
When the measurement intensity of the reference X-ray matches the reference intensity, the intensity of the fluorescent X-ray measured at the correction stage angle is adopted as the measurement intensity, and when it does not match, it matches. The intensity of fluorescent X-rays measured by adjusting the stage angle is adopted as the measurement intensity.
A total reflection X-ray fluorescence analysis apparatus comprising a control means for obtaining a distribution of measurement intensity and updating the correction stage angle based on a stage angle before and after the latest adjustment. A stage capable of moving and tilting the sample is provided. Primary X-rays are incident on a plurality of measurement points on the sample surface at a minute incident angle to measure the intensity of the generated fluorescent X-rays, and the distribution of the measured intensity In the total reflection X-ray fluorescence analyzer for obtaining
For the reference sample, adjust the stage angle so that the incident angle of the primary X-ray is appropriate at the stage position corresponding to each measurement point, and store it as a corrected stage angle.
For the sample to be analyzed, the intensity of the reference X-ray generated uniformly from the surface of the sample is measured as the reference intensity by adjusting the stage angle so that the incident angle of the primary X-ray is appropriate at the reference stage position,
Adjust the correction stage angle at the stage position corresponding to each measurement point, measure the intensity of the fluorescent X-ray and the reference X-ray, and divide by the ratio of the measurement intensity of the reference X-ray to the reference intensity A total reflection X-ray fluorescence analysis apparatus comprising a control means for correcting the measurement intensity of fluorescent X-rays to obtain a distribution of the measured intensity after correction. A stage capable of moving and tilting the sample is provided. Primary X-rays are incident on a plurality of measurement points on the sample surface at a minute incident angle to measure the intensity of the generated fluorescent X-rays, and the distribution of the measured intensity In the total reflection X-ray fluorescence analyzer for obtaining
For the reference sample, adjust the stage angle so that the incident angle of the primary X-ray is appropriate at the stage position corresponding to each measurement point, and store it as a corrected stage angle.
All of the samples to be analyzed are provided with control means for adjusting the correction stage angle at the stage position corresponding to each measurement point, measuring the intensity of the fluorescent X-rays, and obtaining the distribution of the measurement intensity. Reflective fluorescent X-ray analyzer. In any one of Claim 1 to 6,
When a non-reference measurement point that does not match the stage position corresponding to the measurement point of the reference sample is designated as the measurement point of the analysis target sample, the control means, as the correction stage angle of the non-reference measurement point, A total reflection X-ray fluorescence analysis apparatus using a stage angle interpolated based on the correction stage angle of a measurement point where a stage position corresponding to the measurement point of the reference sample matches in the vicinity of the measurement point outside the reference.

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