JP2002214166A - Fluorescent x-ray analyzer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluorescent X-ray analyzer obtaining the distribution of the measured intensity or the like of fluorescent X-rays generated from a sample and capable of making quick measurement with sufficient resolution of distribution measurement. SOLUTION: This fluorescent X-ray analyzer is provided with a plurality of detecting means 6A arranged at different measurement portions 2A in a range P where the primary X-rays 4 from the sample 1 are applied and measuring the fluorescent X-rays 5A generated from the corresponding measurement portions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray fluorescence analyzer for determining the distribution of measured intensity of X-ray fluorescence generated from a sample.

[0002]

2. Description of the Related Art Conventionally, by moving a sample with an XY stage or the like with respect to a fixed X-ray source and a single detecting means, a measurement portion (part of the sample surface and its vicinity in the depth direction) is obtained. Is changed to obtain the distribution of the measurement intensity of the fluorescent X-ray generated from the sample on the sample surface.
There is a line analyzer (see Japanese Patent No. 3122395).

[0003]

However, in such an apparatus, since the measurement portions are measured one by one, the measurement must be performed as many times as the number of the measurement portions.
When it takes T time to measure the number of times (one measurement part), if there are n measurement parts, it takes nT time, that is, n times as a whole, to obtain the intensity distribution, and rapid measurement cannot be performed. On the other hand, if the number n of measurement portions is reduced in order to reduce the overall measurement time, the resolution of distribution measurement may not be sufficient. This problem is particularly serious when the fluorescent X-rays generated from the sample are weak, because even a single measurement takes a long time.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and provides an X-ray fluorescence analyzer for obtaining a distribution of measured intensity of X-ray fluorescence generated from a sample, which has a sufficient resolution of the distribution measurement and a high speed. An object of the present invention is to provide an apparatus capable of performing various measurements.

[0005]

In order to achieve the above object, an apparatus of the present invention irradiates a sample with primary X-rays and measures the intensity of fluorescent X-rays generated or the distribution of analytical values based on the measured intensity. In a fluorescent X-ray analyzer for determining
A plurality of detection means are provided for each of different measurement portions within a range irradiated with the next X-ray and measure the intensity of fluorescent X-rays generated from the corresponding measurement portion.

The X-ray fluorescence spectrometer according to the present invention has the same number of detection means as the number of measurement parts so as to correspond to each of the plurality of measurement parts, and detects the intensity of the fluorescent X-ray generated from each measurement part by the corresponding detection means. Since the measurement can be performed at the same time, the entire measurement can be performed only once. Therefore, when obtaining the distribution of the measurement intensity of the fluorescent X-rays generated from the sample, the resolution of the distribution measurement is sufficient and the measurement can be performed quickly.

In the present invention, a moving means for relatively moving the sample and the plurality of detecting means, for example, a stage for rotating the sample with respect to the plurality of detecting means may be provided.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an apparatus according to a first embodiment of the present invention will be described with reference to the drawings. As shown in the front view of FIG. 1, the apparatus irradiates a sample 1 such as a semiconductor wafer mounted on a sample stage 10 with primary X-rays 4 from an X-ray source 3 such as an X-ray tube to generate a primary X-ray. X-ray fluorescence analyzer for obtaining the measured intensity of the fluorescent X-ray 5 to be measured or the distribution of the analysis value based on the measured intensity, wherein different measurement portions 2A, 2B, 2C within the range of the sample 1 irradiated with the primary X-ray 4 , 2D, and a plurality of detection means 6A,... For measuring the intensity of the fluorescent X-rays 5A,.

As shown in the plan view of the sample 1 and the like in FIG. 2, the sample 1 and the sample stage 10 are disk-shaped with a common center O, while the X-ray source 3 (FIG. Since the primary X-rays 4 (FIG. 1) are radiated with a spread toward the target, the irradiation range of the sample 1 is a circle P indicated by a two-dot chain line in the figure.
In this embodiment, four different measurement portions 2A, 2B, 2C and 2D within this range P are set at equal intervals on the circumference of a concentric circle of the circle P. Each measurement portion 2A is a part of the sample surface indicated by a small circle in FIG. 2 and its vicinity in the depth direction (indicated by a broken line in FIG. 1).

As shown in FIG. 1, four detecting means 6A,... Are provided around the X-ray source 3 corresponding to the four measuring portions 2A,. However, in FIG. 1, the description of the two detectors 6B and 6D arranged at the front and rear in the center is omitted for simplicity. The number and arrangement of the measurement portion and the detection means are not limited to this embodiment.
The detection means 6A,... Of this embodiment are so-called fixed goniometers set for detecting fluorescent X-rays of the wavelength to be measured (common to the plurality of detection means 6A,. Aperture 7A,..., Spectral element 8A,.
, Etc. are provided.

The apertures 7A,... Are tapered and cylindrical so that the detecting means 6A,... Only look at the corresponding measuring portions 2A,. In order to further improve the resolution of the distribution measurement, it is necessary to provide more detection means close to each other. Therefore, it is preferable that the shape of the stop is as narrow as possible within a range where the intensity of the fluorescent X-ray to be captured is not insufficient.
When it is desired to measure the intensity of fluorescent X-rays of a plurality of wavelengths for one measurement part, a part of or all of the detection means is provided with a goniometer in which a spectroscopic element and a detector are linked, instead of a fixed goniometer. Just do it.

Further, this apparatus comprises the following analyzing means 13,
Output means 14 is provided. The analysis means 13 includes in advance the measurement portions 2A,.
And the sample information such as the components of the sample 1 and the layer structure (components of each layer) in the case of a thin film, and the like.
Based on the measured intensities of the fluorescent X-rays 5A,... From the respective detection means 6A,. The output unit 14 outputs the distribution of the measured intensity or the analyzed value of the fluorescent X-rays on the sample surface to a printer (not shown) or a CRT based on the measured intensity or the analyzed value from the analyzing unit 13 and the position information. Display.

As described above, the X-ray fluorescence analyzer of the first embodiment also includes four detection means 6A,... Corresponding to the four measurement portions 2A,. Since the intensity of the fluorescent X-rays 5A generated from the... Can be measured simultaneously by the corresponding detecting means 6A,. Therefore, in obtaining the distribution of the measurement intensity of the fluorescent X-rays 5 generated from the sample 1, the resolution of the distribution measurement is sufficient and the measurement can be performed quickly.

Next, an apparatus according to a second embodiment of the present invention will be described. In this apparatus, as shown in a plan view of the sample 1 and the like in FIG. 3, five different measurement portions 2E, 2F, 2G, and 2 in a range P where the primary X-ray is irradiated on the sample 1.
H, 2I are set radially adjacent from a position in contact with the center O of the circle P, and five measurement portions 2E,.
(Not shown) are provided in correspondence with. Further, the sample stage 10 is fixed on a stage for rotating the sample 1 with respect to five detecting means, that is, a so-called θ stage 11. The rotation center of the θ stage 11 is also the center O. The rest of the configuration is the same as that of the device of the first embodiment, and a description thereof will be omitted.

The X-ray fluorescence spectrometer according to the second embodiment has the same operation and effects as those of the first embodiment in a state where the θ stage 11 is not rotated. Furthermore, when the measurement is performed while rotating the sample 1 on the θ stage 11, a small circle 2
.. (Indicated by a broken line in the figure) including the circular or annular portions 12E,... Including the portions indicated by E,. Also in this case, the fluorescent light X generated from the five measurement portions 12E,.
Since the intensity of the line can be measured simultaneously by the five detecting means corresponding to each, the entire measurement can be performed only once. Therefore, in obtaining the distribution such as the measurement intensity of the fluorescent X-rays generated from the sample 1, the resolution of the distribution measurement can be sufficiently and quickly measured.

[0016]

As described in detail above, the X-ray fluorescence spectrometer of the present invention has the same number of detection means as the number of measurement portions so as to correspond to each of the plurality of measurement portions, and the fluorescence generated from each measurement portion. Since the intensity of X-rays can be measured simultaneously by the corresponding detection means, the entire measurement can be performed only once. Therefore, when obtaining the distribution of the measurement intensity of the fluorescent X-rays generated from the sample, the resolution of the distribution measurement is sufficient and the measurement can be performed quickly.

[Brief description of the drawings]

FIG. 1 is a front view showing a fluorescent X-ray analyzer according to a first embodiment of the present invention.

FIG. 2 is a plan view showing a measurement portion of a sample and the like in the apparatus.

FIG. 3 is a plan view showing a measurement portion of a sample and the like in a fluorescent X-ray analyzer according to a second embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... sample, 2 and 12 ... measurement part, 4 ... primary X-ray, 5 ... fluorescent X-ray generated from a sample, 6 ... detection means, 11 ... stage (moving means) for rotating a sample, P ... 1 in a sample
The range where the next X-ray is irradiated.

Claims (3)

[Claims] An X-ray fluorescence spectrometer for irradiating a sample with primary X-rays to determine a measured intensity of the generated fluorescent X-rays or a distribution of an analysis value based on the intensity, the primary X-rays in the sample are irradiated. An X-ray fluorescence analyzer provided with a plurality of detection means provided for each of different measurement portions within a predetermined range and measuring the intensity of X-ray fluorescence generated from the corresponding measurement portion. 2. The X-ray fluorescence spectrometer according to claim 1, further comprising a moving unit that relatively moves the sample and the plurality of detecting units. 3. The X-ray fluorescence spectrometer according to claim 2, wherein the moving unit is a stage for rotating the sample with respect to the plurality of detecting units.