X-ray beam conditioning device and X-ray analysis apparatus

An X-ray beam conditioning device that has a crystal holder and a motor is provided. The crystal holder supports a first crystal block and a second crystal block, each of which diffracts X-ray by a specific diffraction angle. The motor can rotate the crystal holder around an axis extending at right angles to a plane including an optical axis of X-ray and can fixedly support the crystal holder at the rotated position. The crystal holder holds the first and second crystal blocks at such angles to each other such that both crystal blocks diffract X-ray. The optical axes of the two crystal blocks can be adjusted by rotating the crystal holder about the axis, that is, the only one axis.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an X-ray beam conditioning device such as a monochromator or an analyzer, and an X-ray analysis apparatus which uses an X-ray beam conditioning device.

2. Description of the Related Art

Hitherto, an X-ray beam conditioning device such as a monochromator or an analyzer has been used in X-ray analysis apparatus such as X-ray diffractometer. The monochromator is an X-ray beam conditioning device that is used mainly to perform monochromatization, converting X-rays containing X-rays of different wavelengths to monochromatic X-ray. In most X-ray analysis apparatus, the monochromator is arranged between an X-ray source and a sample (namely, at the upstream side of the sample, with respect to the traveling direction of X-ray).

The analyzer is another type of an X-ray beam conditioning device and used mainly to enhance the angular resolution of X-ray in X-ray analysis apparatuses. In the X-ray analysis apparatus, the analyzer is arranged between the sample and an X-ray detecting means (namely, at the downstream side of the sample, with respect to the traveling direction of X-ray). The analyzer receives, for example, X-ray (e.g., diffracted X-ray, scattered X-ray, reflected X-ray and spectroscopic X-ray) emanating from the sample, and selects X-ray that satisfies predetermined condition of wavelength to emit it to the X-ray detecting means, to thereby enhance the angular resolution of X-ray.

A monochromator of the type shown inFIG. 1Ais known in the art. AsFIG. 1Ashows, two channel-cut crystals101aand101bare arranged in an X-ray path X0. Each of the channel-cut crystals101aand101bis provided with an angle-controlling mechanism, respectively. To adjust the optical axis, the channel-cut crystal101bat downstream side is removed and the channel-cut crystal111aat upstream side is rotated in the direction of arrow A1and set into alignment with the X-ray path X0. Then, the channel-cut crystal101bat downstream side is attached and rotated in the direction of arrow A2, thereby achieving the angle adjustment of the channel-cut crystals101aand101b.

A monochromator of another type shown inFIG. 1Bis known in the art. AsFIG. 1Bshows, this monochromator has mechanisms102aand102bfor moving the channel-cut crystals101aand101b, respectively, away from the X-ray path X0. To adjust the optical axis, one of the channel-cut crystals is moved away from the X-ray path X0as indicated by arrow B1or B2, and the other channel-cut crystal on the X-ray path X0is set into alignment with the X-ray path X0.

Still another type of a monochromator shown inFIG. 2is known in the art. As shown inFIG. 2, axes Xa and Xb for adjusting the angles of the channel-cut crystals101aand101bare located apart from the X-ray path X0. When the optical axis of X-ray is being adjusted, each of channel-cut crystals101aand101bis greatly rotated around the corresponding axis Xa or Xb, thereby moving the channel-cut crystals101aand101boutside of the X-ray path X0. A monochromator of this type is disclosed in, for example,FIG. 1of Jpn. Pat. Appln. Laid-Open Publication No. 9-049811. In this monochromator, the angle adjustment of channel-cut crystals and the mechanism for retreating the crystals from the X-ray path are both accomplished by rotating the crystals around a common axis.

SUMMARY OF THE INVENTION

The conventional monochromator shown inFIG. 1Ahas no mechanisms for retreating the crystals101aand101bfrom the X-ray path X0. Therefore, an operator must manually remove and attach the channel-cut crystals101aand101bin order to adjust the optical axis. In other words, the optical axis cannot be automatically adjusted.

The conventional monochromator illustrated inFIG. 1Bhas indeed mechanisms for retreating the crystals101aand101bfrom the X-ray path X0. However, a crystal-rotating mechanism and a crystal-sliding mechanism must be provided for each channel-cut crystal. These mechanisms are complex in structure. Further, the mechanisms that control them are necessarily complex, too. Consequently, it is very difficult to achieve automatic adjustment of the optical axis. In addition, any apparatus incorporating this monochromator, such as an X-ray analysis apparatus, cannot be formed compact because it should have an inner space in which the channel-cut crystals can move away from the X-ray path X0.

Any channel-cut crystals of four-times reflection type must undergo angle adjustment of very high precision. When one channel-cut crystal is set on the X-ray path X0after it is moved away from the path X0, both channel-cut crystals must be adjusted again in terms of angle. Thus, it is very troublesome to adjust the optical axis.

In the monochromator shown in FIG. 2 of Jpn. Pat. Appln. Laid-Open Publication No. 9-049811, the channel-cut crystals101aand101bare rotated around the axes Xa and Xb through extremely large angles in order to be retreated from the X-ray path X0. Therefore, the angle reproducibility of the channel-cut crystals101aand101bbecomes low. Assume that one of the channel-cut crystals101aand101bis rotated by an angle as large as 180° and moved away from the X-ray path X0, and then is rotated back to an angle position on the X-ray path X0. In this case, this channel-cut crystal may fail to assume an angle position that is identical to the initial one on the X-ray path X0due to an influence of the gear backrush included on a rotation drive mechanism or any other factor. This phenomenon seems to be more prominent as the angle by which the crystal is rotated away from the X-ray path X0increases.

Like the conventional monochromator ofFIG. 1B, the monochromator ofFIG. 2must have an inner space in which the channel-cut crystals can move away from the X-ray path X0. Any apparatus incorporating this monochromator, such as an X-ray analysis apparatus, cannot be formed compact.

The present invention has been made in view of the above-mentioned problems with the conventional X-ray beam conditioning devices. An object of this invention is to provide an X-ray beam conditioning device that is compact and has an optical axis which can be easily adjusted or automatically adjusted. Another object of the invention is to provide an X-ray analysis apparatus that incorporates the X-ray beam conditioning device.

(configuration of the X-Ray Beam Conditioning Device)

An X-ray beam conditioning device according to the present invention comprises: a crystal-supporting means for supporting a first crystal block and a second crystal block, each of which diffracts X-ray by a specific angle; and a crystal-angle adjusting means for rotating the crystal-supporting means around an axis extending at right angles to a plane including an optical axis of the X-ray, and fixedly supporting the crystal-supporting means at thus rotated position; wherein the crystal-supporting means holds the first and second crystal blocks at such angles to each other that both crystal blocks diffract X-ray.

In the X-ray beam conditioning device, the crystal-supporting means holds the first and second crystal blocks, precisely maintaining the crystal blocks at a prescribed angle to each other. Hence, when only one crystal block, for example the first crystal block, is adjusted in terms of angle, the second crystal block is automatically set at a correct angle position. Thus, the second crystal block need not be moved away from the X-ray path or adjusted in terms of angle. It is very easy to adjust the optical axis. The optical axis can therefore be automatically adjusted. Neither the first crystal block nor the second crystal block needs to be moved away from the X-ray path, no space for motion of the crystal blocks is required. Therefore, the X-ray beam conditioning device can be formed compact, and any X-ray analysis apparatus that incorporates the device can be formed compact, too.

In the X-ray beam conditioning device according to the present invention, the first crystal block and the second crystal block are preferably channel-cut crystals. A channel-cut crystal is one formed by cutting a groove (or channel) in a crystal block of germanium, silicon or the like. The opposing sides of the groove can reflect X-ray. If the crystal blocks are channel-cut crystals, the device can completely monochromatise an incident beam and can acquire a high angular resolution.

In the X-ray beam conditioning device according to the present invention, the first crystal block may be positioned nearer an X-ray source than the second crystal block. Then, the crystal-angle adjusting means preferably rotates the crystal-supporting means to change an angle at which X-ray generated by the X-ray source is applied to one X-ray reflecting surface of the first crystal block.

With such a construction, the crystal-angle adjusting means can serve to change the angle at which X-ray is applied to the first crystal block. Moreover, once the first crystal block is set at such a position that it can reflect (or diffract) X-ray, the second crystal block can automatically reflect (or diffract) X-ray, without being adjusted at all.

In the X-ray beam conditioning device according to the present invention, the rotation axis of the crystal-supporting means preferably extends in one X-ray reflecting surface of the first crystal block as shown inFIG. 3, if the first crystal block is positioned nearer an X-ray source than the second crystal block. Alternatively, the rotation axis of the crystal-supporting means may extend in through the first crystal block as is illustrated inFIG. 5A. Still alternatively, the rotation axis of the crystal-supporting means may extend outside the first crystal block and pass a point closer to the X-ray source than to the first crystal block, as is illustrated inFIG. 5C.

In the X-ray beam conditioning device according to the present invention, the crystal-angle adjusting means preferably has a motor whose output shaft can be controlled in terms of rotation angle. In this case, the crystal-supporting means should be coupled directly to the output shaft of the motor. Alternatively, the crystal-angle adjusting means may have a rotary mechanism having a tangent bar. If this is the case, the crystal-supporting means is preferably be secured to an output shaft of the rotary mechanism of tangent bar type.

(Configuration of the X-Ray Analysis Apparatus)

An X-ray analysis apparatus according to the present invention comprises: an X-ray source that generates X-ray to be applied to a sample; an X-ray detecting means for detecting X-ray emitted from the sample; and an X-ray beam conditioning device that is arranged between the X-ray source and the sample. The X-ray beam conditioning device may be constituted by any one of the X-ray beam conditioning devices described above. In the apparatus, the X-ray beam conditioning device is located upstream of the sample. That is, it is of the type in which the X-ray beam conditioning device functions as a monochromator.

The X-ray beam conditioning device according to the present invention can fully monochromatize incident X-ray and can acquire a high angular resolution. Therefore, it can fully perform its function when it is used in an X-ray analysis apparatus that needs to accomplish high-precision measuring. X-ray analysis apparatuses required to accomplish high-precision measuring may be a rocking-curve measuring apparatus, a reciprocal space map measuring apparatus, a reflectivity measuring apparatus, and the like.

The rocking-curve measuring apparatus is an apparatus in which X-ray emanating from a sample is detected by an X-ray detector fixed at a predetermined angular position(2θ) relative to incident X-ray, while changing the incident angle (ω) of X-ray applied to the sample over a very narrow range. Result provided by the apparatus is a rocking curve defined in a coordinate graph by plotting the angle change of sample on the axis of abscissas and plotting the X-ray intensity on the axis of ordinates.

The reciprocal space map measuring apparatus is an apparatus that measures X-ray emanating from a sample by scanning the incident angle(ω) of X-ray applied to the sample while changing the angle(2θ) of an X-ray detector little by little. Result provided by the apparatus is a reciprocal space map in which the incident angles(ω) are plotted on the axis of abscissas and the diffraction angles(2θ) are plotted on the axis of ordinates.

The reflectivity-measuring apparatus is an apparatus that sets an incident angle at which X-ray apply to the sample, to a small angle (for example, 0.1° to 4°), and detects X-ray totally reflected by the sample. Result provided by this apparatus is a reflectivity curve defined in a coordinate graph by plotting the diffraction angle(2θ) on the axis of abscissas and plotting the X-ray intensity I on the axis of ordinates.

An X-ray analysis apparatus according to the present invention comprises an X-ray source that generates X-ray to be applied to a sample, an X-ray detecting means for detecting X-ray emitted from the sample, and an X-ray beam conditioning device that is arranged between the sample and the X-ray detecting means. The X-ray beam conditioning device may be constituted by any one of the X-ray beam conditioning devices described above. In the X-ray analysis apparatus, the X-ray beam conditioning device is located downstream of the sample. In other words, the X-ray analysis apparatus is of the type in which the X-ray beam conditioning device functions as an analyzer.

The X-ray beam conditioning device according to the present invention can fully monochromatize incident X-ray and can acquire a high angular resolution. Therefore, it can fully perform its function when it is used in an X-ray analysis apparatus that needs to accomplish high-precision measuring. X-ray analysis apparatuses required to accomplish high-precision measuring may be a rocking-curve measuring apparatus, a reciprocal space map measuring apparatus, a reflectivity measuring apparatus, and the like.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

First Embodiment of the X-Ray Beam Conditioning Device

An embodiment of the X-ray beam conditioning device according to the present invention will now be described. Needless to say, the present invention is not limited to the embodiment. The devices will be explained with reference to the accompanying drawings. In the drawings, the components of each device may be illustrated in different scales, thus accentuating the characterizing features of the device.

FIG. 3shows an embodiment of an X-ray beam conditioning device according to the present invention. InFIG. 3, the X-ray beam conditioning device1A has a first channel-cut crystal2aused as a first crystal block, a second channel-cut crystal2bused as a second crystal block, a crystal holder3used as crystal-holding means, and a motor4used as crystal-angle adjusting means.

As seen fromFIG. 4, each of the first channel-cut crystal2aand the second channel-cut crystal2bis formed by cutting a groove7in a rectangular parallelepiped block6made of single crystal. The opposite surfaces of the groove7are utilized as reflection surfaces. AsFIG. 3shows, the first channel-cut crystal2areflects, at one reflection surface, X-ray R1emitted from an X-ray generating source G and reflects again thus reflected X-ray at the other reflecting surface, thus emitting X-ray outside. The X-ray generating source G may be an X-ray source composed of a filament and a target, or a sample emitting diffracted X-ray or the like. The second channel-cut crystal2breflects X-ray R2emitted from the first channel-cut crystal2a, at one reflection surface, and reflects again thus reflected X-ray at the other reflecting surface, thus emitting X-ray outside.

X-ray R3emitted from the second channel-cut crystal2bis X-ray that has been obtained by converting the incident X-ray R1to a monochromatic X-ray (i.e., X-ray of a specific wavelength, selected from the incident X-ray R1). The X-ray satisfies a particular angular resolution (that is, the X-ray is selected from the incident X-ray R1that proceed in an emanating state and proceed in a specific angle direction). When the X-ray beam conditioning device1A is used as a monochromator, its function of changing the input X-ray to a monochromatic X-ray is mainly utilized. When the X-ray beam conditioning device1A is used as an analyzer, its function of enhancing angular resolution is mainly utilized.

The first channel-cut crystal2aemits reflected X-ray R2when it is inclined to a specific angle to incident X-ray R1. The second channel-cut crystal2bemits reflected X-ray R3when it is inclined to a specific angle to the first channel-cut crystal2a. The first channel-cut crystal2aand the second channel-cut crystal2bare first inclined relatively at specific angles so as to emit X-ray in such a manner and then secured respectively on the crystal holder3.

The crystals2aand2bare secured to the crystal holder3with high precision in the place where the X-ray beam conditioning device1A is manufactured. Once so secured, neither the first channel-cut crystal2anor the second channel-cut crystal2bwill be adjusted in position at all in the place where the X-ray beam conditioning device1A is utilized. In practice, they may be bonded with use of an adhesive, fastened to the crystal holder3with screws, or secured to the crystal holder3by any other technique. Once the first channel-cut crystal2aand the second channel-cut crystal2bare so inclined relatively and secured at the specific relative angle, they always remain in such conditions that each can reflect and emit X-ray of a specific wavelength, wherever the X-ray beam conditioning device1A is brought and installed.

The crystal holder3is coupled to the output shaft4aof the motor4, at its back surface opposite to the surface that holds the crystals2aand2b. InFIG. 3, the crystal holder3is illustrated as nothing more than a rectangle. In fact, however, it is so shaped and structured as to support both crystals2aand2bfirmly. When the motor4is driven and the output shaft4atherefore rotates, the crystal holder3rotates in the direction of arrow C-C′ around the axis X1of the output shaft4a. The motor4is a motor that can be controlled in rotation angle, such as a pulse motor or a servomotor. The motor4is driven by a signal output from a rotation controller8. The rotation controller8is connected to a host control unit, as needed. The controller8controls the motor4in accordance with a rotation-instructing signal transmitted from the host control unit. The host control unit may be a controller incorporated in an X-ray analysis apparatus. It is, for example, such as an X-ray diffractometer.

The rotation axis X1of the crystal holder3extends in that reflection surface of the first channel-cut crystal2a, which first reflects X-ray. Nonetheless, the axis X1may not be in this reflection surface of the crystal2aand may pass through the crystal2a, as is illustrated inFIG. 5Athat is a plan view of the X-ray beam conditioning device. Alternatively, the axis X1may not be in said reflection surface of the crystal2aand be outside the crystal2a, as is shown inFIGS. 5B and 5C. In the exemplary embodiments ofFIGS. 5B and 5C, the axis X1extends through the crystal2aother than at X-ray reflecting surfaces of said first crystal block. In the exemplary embodiment ofFIG. 5C, the rotation axis X1of the crystal holder3extends outside the crystal2aand passes a point closer to the X-ray source G than to the first crystal2a.

A method in which the X-ray beam conditioning device so configured as described above processes X-rays will be explained below.

(Method of Assembling and Adjusting the Device)

A collimated X-ray has been generated beforehand. The crystal holder3of the X-ray beam conditioning device1A shown inFIG. 3is positioned on the path of the collimated X-ray. At this point, the second channel-cut crystal2bthat lies behind the first channel-cut crystal2ais not mounted on the crystal holder3. Then, the angle of the first channel-cut crystal2ais adjusted on the crystal holder3so that the crystal2amay reflect X-ray. The crystal2a, thus adjusted in angle, is secured to the crystal holder3. Next, the second channel-cut crystal2blying behind is provisionally secured to a position on the crystal holder3and adjusted in terms of angle so that it may reflect X-ray. The second channel-cut crystal2bis then secured to the crystal holder3. Thus, the first channel-cut crystal2aand the second channel-cut crystal2bare secured to the crystal holder3, in a fixed positional relation.

(Method of Performing Minute Adjustment During Use)

An X-ray analysis apparatus to be practically used or an X-ray beam analysis apparatus used as a reference apparatus is adjusted. The reference apparatus is, for example, an apparatus that has a parallel-beam type optical system. The X-ray beam conditioning device1A shown inFIG. 3is incorporated into the X-ray analysis apparatus. In this case, the motor4shown inFIG. 3is coupled to the crystal holder3and then placed at a prescribed position in the X-ray analysis apparatus. If the motor4has already been placed in the X-ray analysis apparatus, the crystal holder3is coupled to the output shaft4aof the motor4.

The rotation controller8gives an instruction, which drives the motor4. As a result, the crystal holder3is scan-rotated in the direction of arrow C-C′. While the scanning rotation of crystal holder3takes place, X-ray emitted from the second channel-cut crystal2b are detected by an X-ray detector. The angular position at which X-ray emitted has the maximum intensity is determined, and the crystal holder3is fixed at this position. When X-ray is Cukα1(having a wavelength of 1.54056 Å) and the crystal is Ge(220), the peak width (i.e., full width of half maximum intensity (FWHM)) of the Cukα1beam is about 0.005°, and the tail width thereof is therefore about 0.015° To measure this peak, it suffices to provide an angle-measuring range of about 0.1°. Thus, an operation range of about 1° is sufficient, including a tolerance for a peak shift.

The data representing the angular position determined as position at which X-ray has the maximum intensity is stored in a storage medium preliminarily provided in the rotation controller8shown inFIG. 3or in an additional storage medium incrementally provided to the rotation controller8. The data representing the position of optical systems other than the X-ray beam conditioning device1A are stored in the storage medium, too.

(Method of Using the Device for Measuring)

In the present embodiment, X-rays having plural wavelengths are diffracted by a crystal four times so that X-ray having a specific wavelength is selected precisely from them. More specifically, in the device ofFIG. 3, CuKα1 (having a wavelength of 1.54056 Å) may be used as X-ray, and a Ge (220) crystal may be used as crystal. In this case, the divergence angle of X-ray emitted from the X-ray beam conditioning device1A can be reduced to about 0.005°. If the X-ray beam conditioning device1A is employed as a monochromator, the divergence angle of X-ray applied to a sample can be decreased to about 0.005°. If the X-ray beam conditioning device1A is employed as an analyzer, an X-ray detector can detect X-ray emitted from a sample with angular resolution of about 0.005°. The X-ray beam conditioning device1A according to this embodiment is fit for use in high-precision measurings, such as measurings for evaluating the single-crystal crystallinity (e.g., rocking-curve measurement and reciprocal-space-map measurement).

(Method of Re-Securing the Device After Minute Adjustment)

Assume that after the minute adjustment described above is completed, the X-ray beam conditioning device1A according to this embodiment is removed from the X-ray analysis apparatus and then secured back to the X-ray analysis apparatus. Then, the X-ray beam conditioning device1A and any other optical system may be moved in accordance with the angular position of the device1A stored in the storage medium, the position of the other optical system and similar factors. This can restore the X-ray optical system to the initial state. The measuring can be started again without the necessity of re-adjusting the X-ray beam conditioning device1A and the like, unless any other components are removed from the X-ray analysis apparatus.

As can be understood from the foregoing, one angle-adjusting device drives a spectral element of four-times reflection type composed of two channel-cut crystals2aand2bin the X-ray beam conditioning device1A according to the present embodiment. The X-ray beam conditioning device1A can therefore be made compact. In addition, four crystal surfaces can be minutely adjusted without using special jigs or without performing a complicated operation. The minute adjustment can therefore be automatically achieved by one simple operation, i.e., rotating the crystal holder3, by using the rotation controller8or any other controller, without the necessity of the operator's labor.

Second Embodiment of the X-Ray Beam Conditioning Device

FIG. 6is a plan view illustrating another embodiment of an X-ray beam conditioning device according to the present invention. This embodiment differs from the embodiment ofFIG. 3in that the drive device for driving the crystal holder3is modified. The component identical to those ofFIG. 3are designated at the same reference numbers inFIG. 6and will not be described in detail.

In the X-ray beam conditioning device1B shown inFIG. 6, the crystal holder3is supported by a rotary mechanism11of tangent bar type. The mechanism11has a rotary stage12fixedly holding the crystal holder3, a control rod13extending outwards from the rotary stage12, an eccentric cam14abutting on the forward end of the control rod13, and a motor15for rotating the eccentric cam14. The rotary mechanism11of tangent bar type is a minute-rotation mechanism that is known in the art. When the eccentric cam14coupled to the motor15is rotated, the control rod13rotates to control the small rotation angle of the rotary stage12. The motion range of the crystal holder3is about 1° only in this embodiment. Hence, the embodiment can use a rotary mechanism11of tangent bar type that has a small effective operation range.

The rotary mechanism11of tangent bar type minimizes the small motion that the crystals undergo when the drive system has a backlash or when power is supplied again to the drive motor, to an angle equal to or smaller than the diffraction-limited angle of the crystals. Hence, the X-ray beam conditioning device1A can operate as if it had four crystals that are completely fixed in place. The crystals may be Ge (440) crystals, and the X-ray applied may be a CuKα1 beam and be separated to the fourth order below the decimal point, i.e., to wavelength of 1.5405 Å. In this case, the minute angle shift of the crystal, which has resulted from the small motion that the crystals undergo when the drive system has a backlash or when power is supplied again to the drive motor, should be reduced to 0.001° or less.

First Embodiment of the X-Ray Analysis Apparatus

FIG. 7shows a first embodiment of an X-ray analysis apparatus according to the present invention. InFIG. 7, the X-ray analysis apparatus21has an X-ray source F for generating X-ray, a monochromator22, a first slit23, a sample holder24, a second slit25, an analyzer26, a third slit27, and an X-ray detector28. The sample holder24supports a sample S to be analyzed, and holds the sample S at a prescribed position. The monochromator22is constituted by an X-ray beam conditioning device of the same type as the device1A shown inFIG. 3or the device1B shown inFIG. 6. The analyzer26is also constituted by an X-ray beam conditioning device of the same type as the device1A shown inFIG. 3or the device1B shown inFIG. 6.

The X-ray source F is of the type in which a filament is heated to emit thermoelectrons, and the thermoelectrons impinge on a target, which emits X-ray. If the target has a surface region made of Cu(copper), it can generate X-ray that contains characteristic X-ray of CuKα. The X-ray detector28is constituted by a so-called zero-dimensional counter that is configured to receive X-ray in a point-shaped region. An example of the zero-dimensional counter is scintillation counter (SC).

X-ray emitted from the X-ray source F is applied to the monochromator22. The monochromator22converts the X-ray to a parallel and monochromatic X-ray. X-ray thus rendered monochromatic and parallel, is applied through the first slit23to the sample S. If the sample S and X-ray applied to it satisfy prescribed conditions, the sample S generates X-ray (e.g., diffracted X-ray, scattered X-ray, reflected X-ray and spectroscopic X-ray). The X-ray emanating from the sample S is applied through the second slit25to the analyzer26. The analyzer26selects X-ray that satisfies a particular angular resolution and emits the X-ray to the downstream side. The X-ray selected is applied through the third slit27to the X-ray detector28. The X-ray detector28generates a signal that corresponds to the intensity of the X-ray it has received. From this signal, there will be calculated the intensity of X-ray. In the ordinary X-ray analysis apparatus, the X-ray intensity I is calculated for each rotation angle (2θ) of the X-ray detector28relative to the incident X-ray, and is stored as measured data in a form of (2θ, I) in a file provided in the storage medium.

The monochromator22and the analyzer26are constituted by an X-ray beam conditioning device of the same type as the device1A shown inFIG. 3or the device1B shown inFIG. 6. Both the monochromator22and the analyzer26may be used, or only one of them may be used. As described above, the spectral element of four-times reflection type composed of two channel-cut crystals2aand2bis driven by one angle-adjusting device in the X-ray beam conditioning device1A or1B according to the present embodiment. The X-ray beam conditioning device1A or the like can therefore be made compact. It follows that the x-ray analysis apparatus21that incorporates two X-ray beam conditioning devices (including the device1A) can be made compact, too.

As pointed out above, four crystal surfaces can be minutely adjusted without using special jigs or without performing a complicated operation in the X-ray beam conditioning device1A or the like. Hence, in the X-ray analysis apparatus21having the X-ray beam conditioning device1A or the like, the monochromator22and the analyzer26can be adjusted very easily. Since four crystal surfaces can be minutely adjusted by one simple operation, i.e., rotating the crystal holder3, the minute adjustment can be automatically achieved by using the rotation controller8or any other controller, without the necessity of the operator's labor. Thus, in the X-ray analysis apparatus21having the X-ray beam conditioning device1A or the like, too, the minute adjustment can be automatically performed on the monochromator22and the analyzer26.

Second Embodiment of the X-Ray Analysis Apparatus

FIG. 8Adepicts another embodiment of an X-ray analysis apparatus according to the present invention. In the embodiment the present invention is applied to a rocking-curve measuring apparatus. Note thatFIG. 8Aonly outlines the X-ray analysis apparatus. Accordingly,FIG. 8Ashows the essential components only, not illustrating the lesser components of this X-ray analysis apparatus.

The rocking-curve measuring apparatus31has an X-ray source F, a monochromator22, a sample holder24, an analyzer26, and an X-ray detector28. The sample holder24supports a sample S to be analyzed, and holds the sample S at a prescribed position. The monochromator22and the analyzer26are each constituted by an X-ray beam conditioning device of the same type as the device1A shown inFIG. 3or the device1B shown inFIG. 6.

In the rocking-curve measuring apparatus31, the X-ray detector28detects X-ray diffracted by the sample S, while it remains at predetermined angle 2θ to the incident X-ray and while the incidence angle ω of X-ray applied to the sample S is changed over a narrow range (namely, small angle range). The measuring results provided by the rocking-curve measuring apparatus31are recorded in the form of a rocking curve L shown inFIG. 8B, in which the sample rocking angle ω is plotted on the axis of abscissas and the X-ray intensity I is plotted on the axis of ordinates.

To enable the rocking-curve measuring apparatus31to provide reliable data, it is desirable to irradiate the sample S with X-ray that has been completely monochromatised. For the same purpose, it is desired that only X-ray satisfying a particular angular resolution be selected and applied to the X-ray detector28. If the monochromator22is constituted by an X-ray beam conditioning device of the same type as the device1A ofFIG. 3or the device1B ofFIG. 6, according to this invention, the sample S can be irradiated with X-ray that has been completely monochromatised. If the analyzer26is constituted by an X-ray beam conditioning device of the same type as the device1A ofFIG. 3or the device1B ofFIG. 6, according to this invention, X-ray satisfying a particular angular resolution can be selected from X-ray emitted from the sample S and can be applied to the X-ray detector28. That is, very reliable data can be obtained if the X-ray beam conditioning device according to this invention is used as a monochromator or analyzer in an apparatus for measuring rocking curves.

Third Embodiment of the X-Ray Analysis Apparatus

FIG. 9Ashows still another embodiment of an X-ray analysis apparatus according to the present invention. In the embodiment the present invention is applied to a reciprocal space map measuring apparatus. It should be noted thatFIG. 9Aonly outlines the X-ray analysis apparatus. Accordingly,FIG. 9Ashows the essential components only, not illustrating the lesser components of this X-ray analysis apparatus.

The reciprocal space map measuring apparatus41has an X-ray source F, a monochromator22, a sample holder24, an analyzer26, and an X-ray detector28. The sample holder24supports a sample S to be analyzed, and holds the sample S at a prescribed position. The monochromator22and the analyzer26are each constituted by an X-ray beam conditioning device of the same type as the device1A shown inFIG. 3or the device1B shown inFIG. 6.

In the reciprocal space map measuring apparatus41, the X-ray detector28detects X-ray diffracted by the sample S, while it gradually changes and sets at angle 2θ to the incident X-ray and while it is scanning the incident angle ω of X-ray applied to the sample S. The results provided by the reciprocal space map measuring apparatus41are recorded as dot data that represents dots in a coordinates plane as is illustrated inFIG. 9B. InFIG. 9B, the incident angle ω of the X-ray is plotted on the axis of abscissas and the diffraction angle 2θ is plotted on the axis of ordinates. The density of each dot data shows the intensity of the diffracted X-ray generated at the sample S.

To enable the reciprocal space map measuring apparatus41to provide reliable data, it is desirable to irradiate the sample S with X-ray that has been completely monochromatised. For the same purpose, it is desired that only X-ray satisfying a particular angular resolution be selected and applied to the X-ray detector28. If the monochromator22is constituted by an X-ray beam conditioning device of the same type as the device1A ofFIG. 3or the device1B ofFIG. 6, according to this invention, the sample S can be irradiated with X-ray that has been completely monochromatised. If the analyzer26is constituted by an X-ray beam conditioning device of the same type as the device1A ofFIG. 3or the device1B ofFIG. 6, according to this invention, X-ray satisfying a particular angular resolution can be selected from X-ray emitted from the sample S and can be applied to the X-ray detector28. That is, very reliable data can be obtained if the X-ray beam conditioning device according to this invention is used as a monochromator or analyzer in an apparatus for measuring reciprocal-space maps.

Fourth Embodiment of the X-Ray Analysis Apparatus

FIG. 10Adepicts still another embodiment of an X-ray analysis apparatus according to this invention. In the embodiment the present invention is applied to a reflectivity measuring apparatus. Note thatFIG. 10Aonly outlines the X-ray analysis apparatus. Accordingly,FIG. 10Ashows the essential components only, not illustrating the lesser components of this X-ray analysis apparatus.

The reflectivity measuring apparatus51has an X-ray source F, a monochromator22, a sample holder24, an analyzer26, and an X-ray detector28. The sample holder24supports a sample S to be analyzed, and holds the sample S at a prescribed position. The monochromator22and the analyzer26are each constituted by an X-ray beam conditioning device of the same type as the device1A shown inFIG. 3or the device1B shown inFIG. 6.

The reflectivity measuring apparatus51operates as will be described below. X-ray is applied to the sample S at a small incident angle ω of, for example, about 0.1° to 4° to thereby totally reflect at the sample S. The X-ray detector28detects X-ray thus reflected, while scanning the sample S within a predetermined angle range around the sample S, and while the detecting angle 2θ of the X-ray detector28is kept at an angle twice as large as the incident angle ω. The scanning operation of the X-ray detector28is referred to as a 2θ/ω scan. In this manner, the structure of, for example, the thin surface region of the sample S is analyzed. The results provided by the reflectivity measuring apparatus51are recorded as data representing such a reflectivity curve H as shown inFIG. 10B. InFIG. 10B, the diffraction angle 2θ is plotted on the axis of abscissas and the X-ray intensity I is plotted on the axis of ordinates. As seen fromFIG. 10B, the total reflection takes place in a region T where the angle 2θ is small and the intensity of the totally reflected X-ray abruptly decreases upon reaching a certain limit.

To enable the reflectivity measuring apparatus51to provide reliable data, it is desirable to obtain a reflectivity curve H that is sharp and not burred. To obtain a sharp reflectivity curve H, it is desirable to irradiate the sample S with X-ray that has been completely monochromatised. Also, it is desired that only X-ray satisfying a particular angular resolution be selected from the sample S and applied to the X-ray detector28. If the monochromator22is constituted by an X-ray beam conditioning device of the same type as the device1A ofFIG. 3or the device1B ofFIG. 6, according to this invention, the sample S can be irradiated with X-ray that has been completely monochromatised. If the analyzer26is constituted by an X-ray beam conditioning device of the same type as the device1A ofFIG. 3or the device1B ofFIG. 6, according to this invention, X-ray satisfying a particular angular resolution can be selected from X-ray emitted from the sample S and can be applied to the X-ray detector28. That is, very reliable data can be obtained if the X-ray beam conditioning device according to this invention is used as a monochromator or analyzer in an apparatus for measuring the reflectivity of samples.

Other Embodiments

The present invention has been explained, describing some preferred embodiments. Nevertheless, the invention is not limited to the embodiments. Various changes and modifications can be made within the scope defined by the claims that will be set forth below.

In the embodiment ofFIG. 3for example, the crystal holder3is depicted as a rectangular one. Nonetheless, the crystal holder3can be shaped and structured differently if necessary. To drive the crystal holder3, the motor4is used in the embodiment ofFIG. 3and the rotary mechanism11of tangent bar type is used in the embodiment ofFIG. 6. A drive mechanism of any other type may be used instead.