JP2973566B2 - X-ray diffractometer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray measurement system capable of easily switching between X-ray measurement using a symmetrical arrangement with a concentrated method and X-ray measurement using an asymmetrical arrangement with a parallel method without replacing or adjusting optical systems. The present invention relates to a line diffraction device.

[0002]

2. Description of the Related Art Generally, when a thin film is formed on a base metal by ion plating, CVD, or the like, the crystal orientation and the state of development of crystal grains of the thin film differ depending on the forming conditions. In particular, physical properties such as adhesion to a base metal and abrasion resistance change depending on the difference in orientation. Therefore, it is important to examine the influence of the orientation of the thin film crystal formed on such a base metal.

On the other hand, in the measurement by an X-ray diffractometer, a so-called symmetric arrangement in which the X-ray source and the X-ray detector are arranged so that they are always symmetrical with respect to an axis passing through the sample,
There is a so-called asymmetric arrangement in which the radiation source and the X-ray detector are arranged so that they are located at asymmetric positions.

[0004] In the asymmetrical arrangement, an X-ray source, a sample, and a detection slit are arranged on a focal circle in order to satisfy a concentration condition for diffracted X-rays. There is a parallel method in which a slit is provided to detect only a specific diffracted X-ray. However, in the former method, the size of the apparatus is increased to satisfy the arrangement condition. Adopted. Therefore, hereinafter, the asymmetric arrangement refers to the parallel asymmetric arrangement.

The above-described measurement of the symmetrical arrangement is a method usually employed when qualitative analysis or the like is performed on a polycrystal sample or a powder sample.
The line detector is rotated by a double angle of 2θ.

The measurement of the asymmetric arrangement in the parallel method is usually performed by
This method is used to increase the apparent thickness of a thin film sample with respect to X-rays incident on the sample. The sample is fixed so that the incident angle of X-rays is constant, and only the X-ray detector rotates. So that the goniometer is driven.

By the way, to examine the orientation of the crystal, X
There is a method of performing measurement in which the above-described symmetric arrangement and asymmetric arrangement are combined using a line diffraction apparatus.

For this purpose, first, a symmetrical arrangement of a crystal sample having an orientation is measured. In this measurement, X-rays diffracted on a crystal plane satisfying the Bragg condition are detected. Then, from the X-ray diffraction data obtained by this, 1
The ratio between the peak intensities of the specific crystal planes of the set is determined, and this is determined as the relative intensity a.

Next, the same sample is measured for an asymmetric arrangement. In this asymmetric arrangement, the crystal sample having the orientation does not satisfy the Bragg diffraction condition with respect to the oriented crystal plane, so there is no information on the orientation, and therefore, the powder sample which is not affected by the orientation is used. X-ray diffraction results similar to the above data are obtained.

Then, from the X-ray diffraction data, the ratio of the peak intensities of a set of specific crystal planes, which is the same as in the case of the measurement of the symmetrical arrangement, is obtained, and this is determined as a relative intensity b.

Subsequently, the ratio of the above relative intensities (= a /
b) is standardized, and this is defined as an orientation degree that indicates a measure of the degree of orientation.

According to this method, the degree of orientation can be determined only by the measurement sample, and there is no need for a standard powder sample or an existing database, so that existing data cannot be used.
It has the feature that it can be used for completely new substances.

[0013]

According to the method described above,
In order to examine the orientation of a crystal sample using an X-ray diffractometer, it is necessary to perform measurement of a symmetric arrangement and measurement of an asymmetric arrangement, respectively. , Coordination becomes essential.

For example, in order to switch from symmetric arrangement measurement to asymmetric arrangement measurement, the θ-2θ interlocking mechanism is disconnected, and the divergence slit disposed between the X-ray source and the sample is changed from a wide one to a narrow one. And the detection slit disposed between the sample and the X-ray detector must be replaced with a solar slit. In addition, when a solar slit is used, the intensity of the X-rays incident on the X-ray detector varies greatly due to a slight difference in the arrangement angle. Therefore, it is necessary to adjust the arrangement angle to be appropriate. Therefore, replacement and adjustment are troublesome.

In order to save the trouble of replacing and adjusting the optical system, in the prior art, two goniometers are juxtaposed, one of which has an optical system dedicated to measurement in a symmetrical arrangement, and the other has an asymmetrical arrangement. An apparatus has been provided in which an optical system dedicated to measurement can be installed in advance.

However, such a configuration not only increases the size of the entire apparatus but also increases the cost.

[0017]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and is intended to measure the symmetric arrangement and asymmetric arrangement necessary for examining the orientation of a crystal sample. And the measurement can be automatically performed without switching the optical system each time, so that the trouble of replacing and adjusting the optical system can be omitted, and the size and cost of the apparatus can be reduced.

Therefore, in the present invention, an X-ray source and a goniometer are provided, and the goniometer is provided with a θ-rotating part provided at the center position of the diffractometer circle and a 2θ-rotating part moved along the diffractometer circle. An X-ray diffraction apparatus having a detector holder on the 2θ rotation unit has the following configuration.

That is, in the X-ray diffractometer of the present invention, the first optical system comprising the slit and the first X-ray detector and the second optical system comprising the solar slit and the second X-ray detector are provided on the detector holder. The optical system is arranged side by side at a predetermined angle, and a drive unit for individually driving these is connected to the θ rotation unit and the 2θ rotation unit, while a first X-ray detector and a second X-ray detection unit are connected. An output selection unit for selecting one of the outputs of the detector, a symmetric arrangement mode in which the relationship between the X-ray source and the first optical system is symmetrically arranged with respect to the sample, and a relationship between the X-ray source and the second optical system A mode setting unit that selects an asymmetric arrangement mode in which the asymmetric arrangement is performed, and the mode setting unit
When the symmetric arrangement mode is selected, the θ rotation unit and 2θ
A control signal for driving the rotating unit while maintaining the relationship of θ−2θ is provided to the driving unit, a control signal for selecting an output of the first X-ray detector is output to the output selecting unit, and the asymmetric arrangement mode is used. When selected, the θ rotation unit is fixed at a predetermined angle and a control signal for driving only the 2θ rotation unit is output to the drive unit, and a control signal for selecting the output of the second X-ray detector is output. And a controller for outputting to the selection unit.

[0020]

In the above configuration, when the symmetric arrangement mode is selected by the mode setting section, the controller controls the drive section in accordance with the selection, so that the .theta.
The rotation unit is driven while maintaining the relationship of θ−2θ, and the controller controls the output selection unit to select the output of the first X-ray detector. As a result, the measurement in the symmetric arrangement is performed.

On the other hand, when the asymmetric arrangement mode is selected, the controller controls the drive unit in response to this, so that the θ rotation unit is fixed and only the 2θ rotation unit is driven, and the controller selects the output selection. Control the 2nd X
Select the output of the line detector. Thereby, the measurement of the asymmetric arrangement is performed.

As described above, the first optical system and the second optical system are set in advance in a state where they are properly adjusted on the same detector holding table, and the θ rotation unit and 2θ are set in accordance with each mode selection.
Since the operation of the rotating unit is controlled, each measurement result according to the symmetric arrangement and the asymmetric arrangement can be automatically obtained without replacing or adjusting the optical system as in the related art.

[0023]

FIG. 1 is a block diagram of an X-ray diffraction apparatus according to an embodiment of the present invention.

In FIG. 1, P is an X-ray source comprising an X-ray tube, and G is a goniometer. This goniometer G is
It has a θ rotation part H arranged at the center position O of the diffractometer circle R, and a 2θ rotation part I scanned along the diffractometer circle R. A detector holder J is attached to the 2θ rotation unit I.

On this detector holder J, a slit S ₁
When the first optical system B ₁ consisting of the 1X-ray detector DT ₁ Tokyo, first comprising a Soller slit S ₂ first 2X-ray detector DT ₂ Metropolitan 2
An optical system B ₂ are juxtaposed apart by a predetermined angle alpha.

S ₀ is a divergence slit disposed between the X-ray source P and the θ rotation unit H, and DR is a drive unit.

The driving unit DR drives the slit driving unit D ₀ for adjusting the slit width of the divergent slit S ₀ , the θ driving unit D ₁ for driving the θ rotating unit H to rotate, and the rotary driving of the 2θ rotating unit I. Drive units D _2, and each of the drive units D _{0 to} D ₂
Is configured by combining a pulse motor and a gear, for example.

SW is an output selection unit for selecting one of the outputs of the first X-ray detector DT ₁ and the second X-ray detector DT ₂ , and is constituted by, for example, a changeover switch.

U is a mode setting section operated when selecting the symmetric arrangement mode or the asymmetric arrangement mode, and is constituted by a keyboard, for example.

C is a controller, for example, CP
U, and controls the drive unit DR and the output selection unit SW according to each arrangement mode set by the mode setting unit U.

Next, the operation of the X-ray diffraction apparatus having the above configuration will be described.

When the symmetrical arrangement mode is selected by the mode setting unit U, the controller C drives the slit driving unit D ₀ in response to the selected mode so that the diverging slit S ₀ has a predetermined diverging angle. Set the width. Further, it switches the connection to the 1X-ray detector DT ₁ side controls the output selection unit SW.

Subsequently, control signals are output to the θ drive unit D ₁ and the 2θ drive unit D ₂ to drive both drive units D ₁ and D ₂ . Thus, when the sample A on the θ rotation unit H rotates by θ, the 2θ rotation unit I is scanned by 2θ.

Therefore, the X-rays from the X-ray source P are diffracted by the sample A arranged on the sample stage of the θ-rotation unit H, and the diffracted X-rays pass through the slit S ₁ and the first X-ray detector DT Detected at ₁ . Then, the detection output of the _first X-ray detector DT1 is input to the controller C via the output selection unit SW, and the X-ray diffraction data in the symmetric arrangement is measured.

On the other hand, when the asymmetric arrangement mode is selected by the mode setting unit U, the controller C drives the slit driving unit D ₀ in response to the selection to drive the divergent slit S _0.
Is set to a smaller divergence angle (for example, 2 ° or less) than in the case of measurement in a symmetric arrangement. Also,
The output selector SW is controlled to switch the connection to the _second X-ray detector DT2.

Subsequently, the controller C controls the θ drive unit D ₁
To output the control signal to stop the output of the control signal when the sample A reaches the predetermined incident angle β.

Next, the controller C includes a 2θ driving unit D ₂
And outputs the control signal only to the 2θ rotation unit H to rotate the control signal. As a result, the 2θ rotation unit I is scanned while the sample A is fixed at the predetermined incident angle β.

Therefore, the X-rays from the X-ray source P are diffracted by the sample A, and the diffracted X-rays are detected by the _second X-ray detector DT ₂ through the solar slit S ₂ . And the second
The detection output of the X-ray detector DT ₂ is inputted to the controller C via the output selection unit SW, X-ray diffraction data by the asymmetrical arrangement is measured. In this case, since the first optical system B ₁ represents the second optical system B ₂ has misaligned by an angle alpha, the controller C corrects angle fraction alpha being misaligned diffraction angles measured .

As described above, the first optical system B ₁ and the second optical system B ₂ are set in advance on the same detector holder J in an appropriately adjusted state, and are set in accordance with each mode selection. Since the operations of the θ rotation unit H and the 2θ rotation unit I are controlled, each measurement according to the symmetric arrangement and the asymmetric arrangement can be performed with a single sample setting without replacing or adjusting the optical system as in the related art. The result will be obtained automatically.

The X-ray diffraction data obtained according to each mode is processed in the controller C,
The relative intensity ratio (= a / b) based on the measurement of each arrangement is calculated to determine the degree of orientation.

[0041]

According to the present invention, the measurement of the symmetric arrangement and the measurement of the asymmetric arrangement, which are necessary when the orientation of a thin film sample is examined using an X-ray diffractometer, are automatically performed according to the mode setting. Since the switching can be performed in a timely manner, it is possible to save the trouble of replacing and adjusting the optical system at the time of measuring both arrangements.

In addition, since only one goniometer is required,
The device can be reduced in size and cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an X-ray diffraction apparatus according to an embodiment of the present invention.

[Explanation of symbols]

R: diffractometer circle, P: X-ray source, G: goniometer, A: sample, H: θ rotating part, I: 2θ rotating part, B ₁
... First optical system, S ₁ ... Slit, DT ₁ ... First X-ray detector, B ₂ ... Second optical system, S ₂ ... Solar slit, TD ₂ ...
2nd X-ray detector, DR: drive unit, SW: output selection unit, U
... Mode setting part, C ... Controller.

Claims (1)

(57) [Claims] An X-ray source (P) and a goniometer (G), wherein the goniometer (G) is provided with a θ rotating part (H) provided at a center position of a diffractometer circle (R), and a diffractor. An X-ray diffractometer having a 2θ rotating section (I) scanned along the meter circle (R), wherein the 2θ rotating section (I) is provided with a detector holder (J). A first optical system (B ₁ ) consisting of a slit (S ₁ ) and a first X-ray detector (DT ₁ ), a solar slit (S ₂ ) and a second X-ray detector (DT ₂ ) and the second optical system (B ₂ )
(α) apart from each other, and the θ rotation unit (H) and the 2θ rotation unit (I) are respectively provided with a drive unit for individually driving them.
(DR) is connected, an output selector (SW) for selecting one of the outputs of the first X-ray detector (DT ₁ ) and the second X-ray detector (DT ₂ ), and a sample (A). Regarding the X-ray source (P)
When the first optical system (B ₁₎ and the symmetrical placement mode and X-ray source to symmetrically place the relationship (P) and a second optical system (B ₂₎ and the relationship between asymmetrical arrangement mode of asymmetric arrangement, respectively When a symmetric arrangement mode is selected by the mode setting unit (U) to be selected and the mode setting unit (U), the θ rotation unit (H) and the 2θ
A control signal for driving the rotating unit (I) while maintaining the relationship of θ-2θ is given to the driving unit (DR), and a control signal for selecting an output of the _first X-ray detector (DT ₁ ) is output to an output selecting unit. (S
W), and when the asymmetric arrangement mode is selected, a control signal that drives only the 2θ rotation unit (I) while fixing the θ rotation unit (H) at a predetermined angle is output to the drive unit (DR). ) And a controller (c) for outputting a control signal for selecting the output of the _second X-ray detector (DT ₂ ) to an output selector (SW). .