JP2006177842A - Cut face inspection device and cut face inspection method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cut face inspection device and a cut face inspection method capable of evaluating accurately a cut face of a quartz plate regardless of the attitude of the quartz plate to a sample stand. <P>SOLUTION: This device is equipped with the sample stand for supporting a sample cut at a prescribed angle with respect to a crystal lattice face, a rotating means for rotating the sample stand, an X-ray detection means for detecting a diffracted X-ray of the X-ray diffracted by the sample, a detection means of a reflection laser beam to be detected, a cut face actual angle detection means for detecting a cut face actual angle of the cut face relative to a reference horizontal plane based on the detected reflection laser beam, a correction means for correcting a rotation angle of the sample stand relative to the reference horizontal plane by using the cut face actual angle, and an evaluation means for evaluating the cut face based on the corrected rotation angle and the detected diffracted X-ray. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a cut surface inspection device such as a crystal plate and a cut surface inspection method.

  In recent years, quartz plates (blanks) such as quartz wafers and chips have been used as vibrators and oscillators in watches and mobile phones. This quartz plate is formed by cutting a bar of artificial quartz into a thickness of about 0.2 mm. In this case, it is known that the angle of inclination of the cut surface with respect to the crystal lattice plane inside the crystal plate determines characteristics such as the frequency as a vibrator, and a crystal plate having desired characteristics (for example, an AT cut of crystal) In order to obtain a plate, an artificial quartz bar is cut at a predetermined inclination angle. Actually, even if the cut is set at a predetermined tilt angle, there may be a variation in the tilt angles in the cut quartz plates, so that the deviation amount from the predetermined tilt angle is large. Sorting work is being done. Therefore, in order to improve the quality accuracy of the quartz plate, it is required to measure the tilt angle with high accuracy.

  In general, the tilt angle of the cut surface of the crystal plate is measured by irradiating the crystal plate with X-rays, measuring the X-rays diffracted by the crystal lattice plane inside the crystal plate, and shifting to a predetermined tilt angle. It is performed using a cut surface inspection device for inspecting the amount. In this case, in the cut surface inspection apparatus, the crystal plate is supported by a sample stand or the like, and the cut surface is inspected by irradiating the crystal plate with X-rays while the sample stand is inclined at various angles. When the quartz plate is tilted with respect to the sample stage, the measured tilt angle may not be accurate, and various ideas have been devised for supporting the quartz plate.

  For example, Patent Document 1 describes a technique in which a crystal plate is placed on a sample table on which a plurality of linear protrusions are formed, and a cut surface of the crystal plate is inspected. Patent Document 2 describes a technique for inspecting a cut surface by adsorbing a cut surface of a crystal plate on a sample table.

JP-A-6-174661 JP 2000-269765 A

  Here, recently, in order to improve the efficiency of work related to the inspection of the cut surface of the crystal plate, one inspection is performed on a crystal plate of a relatively large size (for example, a crystal plate of 1 inch or more). Is required. However, in the technique described in Patent Document 1 above, since the sample stage supports the crystal plate with a small area, if a large size crystal plate is placed on the sample stage, the crystal plate is warped by gravity. In some cases, the cut surface could not be accurately inspected. Further, in the technique described in Patent Document 2, since the crystal plate is supported by the surface, the crystal plate does not warp by its own weight, but when dust or dust enters between the crystal plate and the sample stage. In this case, since the quartz plate is inclined with respect to the sample stage, the cut surface cannot be accurately inspected. In this case, if even a minute dust of about 1 μm enters between the crystal plate and the sample stage, the accuracy of inspection is greatly affected.

  Examples of the problem to be solved by the present invention are as described above. An object of the present invention is to provide a cut surface inspection apparatus and a cut surface inspection method capable of accurately evaluating a cut surface of a crystal plate regardless of the orientation of the crystal plate with respect to a sample stage.

  In the invention according to claim 1, the cut surface inspection apparatus includes a sample stage that supports a sample cut at a predetermined angle with respect to the crystal lattice plane, and an axis that is horizontal to the cut surface of the sample. Rotating means for rotating the sample stage, X-ray irradiating means for irradiating the sample with X-rays, X-ray detecting means for detecting diffracted X-rays of the X-ray diffracted by the sample, and the sample A laser beam irradiating means for irradiating a laser beam, a reflected laser beam detecting means for detecting the reflected laser beam incident upon the reflected laser beam reflected by the sample, and the detected reflected laser beam. The cut surface actual angle detecting means for detecting the cut surface actual angle of the cut surface with respect to a reference horizontal plane, and the sample table with respect to the reference horizontal plane using the cut surface actual angle. And correcting means for correcting a rotation angle, the rotation angle is corrected, and based on the detected diffracted X-rays, characterized in that it comprises an evaluation unit for evaluating the cut surface.

  In a sixth aspect of the present invention, a sample stage for supporting a sample cut at a predetermined angle with respect to a crystal lattice plane, and a rotation for rotating the sample stage about an axis horizontal to the cut plane of the sample A cut surface inspection method using an inspection apparatus including means includes: an X-ray irradiation step of irradiating the sample with X-rays; and an X-ray detection step of detecting diffracted X-rays of the X-ray diffracted by the sample And a laser beam irradiation step of irradiating the sample with a laser beam, a reflected laser beam detection step of detecting the reflected laser beam by the incident of the reflected laser beam reflected by the sample and detecting the reflected laser beam, Based on the reflected laser beam, the cut surface actual angle detection step for detecting the cut surface actual angle of the cut surface with respect to a reference horizontal plane, and the reference horizontal using the cut surface actual angle. A correction step of correcting the rotation angle of the sample stage with respect to the above, and an evaluation step of evaluating the cut surface based on the corrected rotation angle and the detected diffraction X-ray. To do.

  In a preferred embodiment of the present invention, the cut surface inspection apparatus includes a sample stage that supports a sample cut at a predetermined angle with respect to the crystal lattice plane, and an axis that is horizontal to the cut surface of the sample. Rotating means for rotating the sample stage, X-ray irradiating means for irradiating the sample with X-rays, X-ray detecting means for detecting diffracted X-rays of the X-ray diffracted by the sample, and the sample A laser beam irradiating means for irradiating a laser beam, a reflected laser beam detecting means for detecting the reflected laser beam incident upon the reflected laser beam reflected by the sample, and the detected reflected laser beam. The cut surface actual angle detecting means for detecting the actual cut surface angle of the cut surface with respect to a reference horizontal plane, and the sample with respect to the reference horizontal plane using the cut surface actual angle. Comprises a correcting means for correcting the rotation angle of the rotation angle is corrected, and based on the detected diffracted X-ray, and evaluating means for evaluating the cutting surface.

  The cut surface inspection apparatus is suitably used for inspecting a cut surface of a crystal plate or the like cut at a predetermined angle with respect to the crystal lattice plane. The cut surface inspection apparatus includes a sample stage for supporting a sample, a rotating means for rotating the sample stage around an axis parallel to the cut surface of the sample, an irradiation means for irradiating the sample with X-rays, and a sample. X-ray detection means for detecting diffracted X-rays, laser beam irradiation means for irradiating a sample with a laser beam, and reflected laser beam detection means for detecting a reflected laser beam reflected by the sample. Further, the cut surface actual angle detecting means detects the cut surface actual angle of the cut surface with respect to the reference horizontal plane based on the reflected laser beam detected by the reflected laser beam, and the correcting means uses the cut surface actual angle, The rotation angle of the sample stage relative to the reference horizontal plane is corrected, and the evaluation unit evaluates the cut surface based on the corrected rotation angle and the detected diffraction X-ray. Thus, even if the cut surface is tilted with respect to the sample table, in other words, even if the cut surface is not horizontal with respect to the sample table, the cut surface inspection device can accurately calculate based on the corrected rotation angle of the sample table. The cut surface can be evaluated. That is, the cut surface inspection apparatus can accurately evaluate the cut surface based on the corrected rotation angle of the sample table regardless of the posture of the sample with respect to the sample table. Therefore, for example, when the sample is surface-supported with respect to the sample stage, there may be a problem that the cut surface is inclined with respect to the sample stage due to dust or the like being sandwiched between the sample stage and the sample. The cut surface inspection apparatus can accurately evaluate the cut surface of the sample even if such a problem occurs.

  In one aspect of the cut surface inspection apparatus, the evaluation unit evaluates the cut surface based on the corrected rotation angle when the detected intensity of the diffracted X-ray is maximized.

  In this aspect, the cut surface inspection apparatus evaluates the cut surface of the sample by using the rotation angle of the sample table when the intensity of the detected diffraction X-ray is maximum. Specifically, the cut surface inspection apparatus uses the rotation angle of the sample table when the intensity of diffracted X-rays is maximum in a sample cut accurately at a set predetermined tilt angle as a reference rotation angle, and measures Cut the sample based on the difference between the rotation angle of the sample table (the corrected rotation angle described above) and the reference rotation angle when the intensity of the diffracted X-ray is maximum in the target sample. The surface can be evaluated.

  In the other one aspect | mode of said cut surface inspection apparatus, the said sample stand surface-supports the said sample in the said cut surface.

  In this aspect, the sample stage of the cut surface inspection apparatus supports the sample on the cut surface. Since the cut surface inspection apparatus corrects the rotation angle in consideration of the inclination of the cut surface with respect to the sample table, the cut surface can be accurately evaluated even if the cut surface is inclined with respect to the sample table. Therefore, the cut surface inspection apparatus can accurately evaluate the cut surface even if the sample is surface-supported on the sample stage. That is, the cut surface inspection apparatus can accurately evaluate the cut surface without performing measurement by supporting the sample on the sample stage (for example, supporting three points). As a result, when a sample of a large size is point-supported, it may be warped due to its own weight and cannot be measured accurately. However, the cut surface inspection apparatus can appropriately cope with a problem caused by surface support. Therefore, such a large sample can be supported on the surface and the cut surface can be accurately evaluated. Therefore, since the cut surface inspection apparatus can evaluate a cut surface at a time for a large-sized sample, it is possible to reduce the time required for evaluating the cut surface of the sample. Furthermore, by supporting the sample on the surface, multipoint measurement can be easily performed by repositioning the sample stage.

  In another aspect of the cut surface inspection apparatus, the cut surface actual angle detection unit detects the cut surface actual angle based on a position of a beam spot formed by the reflected laser beam. In this aspect, the cut surface actual angle detecting means can obtain the cut surface actual angle based on the coordinates of the beam spot formed by the reflected laser beam.

  In one preferred example, the correction means can correct the rotation angle when starting the evaluation of the cut surface.

  In another embodiment of the present invention, a sample stage for supporting a sample cut at a predetermined angle with respect to a crystal lattice plane, and a rotation for rotating the sample stage about an axis horizontal to the cut plane of the sample A cut surface inspection method using an inspection apparatus including means includes: an X-ray irradiation step of irradiating the sample with X-rays; and an X-ray detection step of detecting diffracted X-rays of the X-ray diffracted by the sample And a laser beam irradiation step of irradiating the sample with a laser beam, a reflected laser beam detection step of detecting the reflected laser beam by the incident of the reflected laser beam reflected by the sample and detecting the reflected laser beam, Based on the reflected laser beam, the cut surface actual angle detection step for detecting the cut surface actual angle of the cut surface with respect to a reference horizontal plane, and the reference horizontal using the cut surface actual angle. Comprising a correction step of correcting a rotation angle of the sample stage relative to the rotational angle is corrected, and based on the detected diffracted X-ray, and a evaluation step for evaluating the cut surface. Even with the cut surface inspection method described above, the cut surface inspection apparatus can accurately evaluate the cut surface based on the corrected rotation angle of the sample table regardless of the posture of the sample with respect to the sample table.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the present specification, in the cut surface inspection apparatus, a horizontal plane serving as a reference for the entire apparatus, in other words, a horizontal plane on which the apparatus is arranged is used as a “reference horizontal plane”.

[Configuration of cut surface inspection device]
First, a cut surface inspection apparatus 100 according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram showing a schematic configuration of the cut surface inspection apparatus 100.

  The cut surface inspection apparatus 100 mainly includes an X-ray source 1 as an X-ray irradiation unit, an X-ray detector 2 as an X-ray detection unit, a laser beam irradiation unit 3 as a laser beam irradiation unit, and a reflection laser. A laser beam receiving unit 4 as a beam detecting unit, a goniometer 5 as a rotating unit, and a control unit 8 are provided. The cut surface inspection device 100 is a device that mainly performs measurement on the cut surface 10a of the crystal plate 10 serving as a sample. The crystal plate 10 is cut at a predetermined inclination angle with respect to the crystal lattice plane.

  The goniometer 5 has a sample stage 6, and the crystal plate 10 is placed on the sample stage 6. In this case, the crystal plate 10 is surface-supported on the surface 6a of the sample stage 6 at the cut surface 10a. The sample stage 6 rotates in a direction indicated by an arrow ω about an axis horizontal to the cut surface 10a of the crystal plate 10 and the surface 6a of the sample stage 6. As a result, the angle of the quartz plate 10 with respect to the reference horizontal plane changes, and the incident angles of an X-ray XR and a laser beam LB incident on the quartz plate 10 described later change. The goniometer 5 is controlled by a control signal S3 supplied from the control unit 8. In this case, the goniometer 5 rotates the sample stage 6 by an angle corresponding to the supplied control signal S3. The goniometer 5 is a device that can rotate the sample stage 6 with high accuracy.

  Here, the rotation angle of the sample stage 6 will be defined with reference to FIG. FIG. 2 is a diagram of the crystal plate 10 and the sample stage 6 observed from the side. As shown in the figure, it can be seen that the sample stage 6 is inclined with respect to the reference horizontal plane 20 by an angle α1. In this case, the sample stage 6 is rotated by the goniometer 5 at the rotation angle α1.

  Returning to FIG. The X-ray source 1 irradiates the crystal plate 10 with X-rays XR from below the crystal plate 10 (indicated by a dotted line in FIG. 1). In this case, the X-ray XR passes through a not-shown slot provided in the sample stage 6 and is incident on the bottom surface of the crystal plate 10. This slot is provided in a part of the place on the sample stage 6 where the crystal plate 10 is placed. The quartz plate 10 diffracts on the crystal lattice plane inside the quartz plate 10 when X-rays XR are incident at a predetermined incident angle. Specifically, when the X-ray XR is incident on the quartz plate 10 at a predetermined incident angle, diffracted light having the maximum intensity is generated. The X-ray detector 2 receives the diffracted X-ray RXR diffracted by the cut surface 10a of the quartz plate 10 and detects the incident diffracted X-ray RXR. The X-ray detector 2 supplies the control unit 8 with a signal S1 corresponding to the detected diffracted X-ray RXR.

  The laser beam irradiation unit 3 emits a laser beam LB from above the crystal plate 10 to the crystal plate 10 (indicated by a one-dot chain line in FIG. 1). The laser beam LB is reflected by the quartz plate 10, and the reflected laser beam RLB reflected is incident on the laser beam receiving unit 4. The laser beam receiving unit 4 supplies a signal S2 corresponding to the received reflected laser beam RLB to the control unit 8.

  The control unit 8 includes a personal computer (PC) 8a and a monitor 8b. The PC 8a acquires a signal S1 corresponding to the diffracted X-ray RXR detected from the X-ray detector 1 and a signal S2 corresponding to the reflected laser beam RLB detected from the laser beam receiving unit 4. Furthermore, the PC 8a supplies the signal S3 to the goniometer 5 and controls the sample stage 6 so as to be inclined at a desired angle with respect to the reference waterside surface 20.

  The PC 8a evaluates the cut surface 10a of the crystal plate 10 based on the information on the diffracted X-ray RXR supplied as the signal S1 and the information on the reflected laser beam RLB supplied as the signal S2. Specifically, the PC 8 a evaluates the inclination angle of the cut surface 10 a with respect to the crystal lattice plane of the crystal plate 10. For example, the PC 8a can evaluate the cut surface 10a of the crystal plate 10 based on the measured deviation amount of the inclination angle with respect to a predetermined inclination angle. In this case, the PC 8a evaluates the cut surface 10a of the crystal plate 10 using the rotation angle of the sample stage 6 when the intensity of the diffracted X-ray RXR detected by the X-ray detector 2 is maximum. Specifically, the PC 8a uses the rotation angle of the sample stage 6 when the intensity of the diffracted X-ray RXR is maximum in the quartz plate 10 that has been accurately cut at a set predetermined tilt angle as a reference rotation angle. The cut surface 10a of the crystal plate 10 is evaluated by the magnitude of the difference between the rotation angle of the sample stage 6 when the intensity of the diffracted X-ray RXR is maximum in the crystal plate 10 and the reference rotation angle. Can do.

  Further, the PC 8a creates a display image such as a graph showing a change in the intensity of the diffracted X-ray RXR with respect to the rotation angle of the sample stage 6 and an image of a beam spot formed by the reflected laser beam RLB, which will be described later, and monitors them. 8b. The monitor 8b displays a display image supplied from the PC 8a. As described above, the control unit 8 functions as an evaluation unit that evaluates the cut surface 10 a of the crystal plate 10.

[Diffraction X-ray measurement example]
Next, a specific example of the diffracted X-ray RXR detected by the X-ray detector 2 will be described with reference to FIG.

  FIG. 3A is a view of the crystal plate 10, the sample stage 6, the X-ray source 1, and the X-ray detector 2 observed from the side. FIG. 3A shows a diagram when diffraction of X-ray XR occurs in the quartz plate 10. In this case, diffraction occurs when the X-ray XR is incident on the cut surface 10a of the quartz plate 10 at an incident angle θ.

  If the angle (tilt angle) formed by the cut surface 10a with respect to the crystal lattice plane inside the quartz plate 10 is ε, an angle θb (θb = θ) obtained by adding / subtracting the incident angle θ of the X-ray XR and the angle ε. ± ε) is the so-called “Bragg angle”. In addition, the Bragg angle θb is generally expressed using the equation (1), using the wavelength λ of the X-ray XR and the crystal lattice plane distance d inside the quartz plate 10.

λ = 2 dsin (θb) Equation (1)
FIG. 3B is a diagram showing the relationship between the rotation angle (horizontal axis) of the sample stage 6 and the intensity (vertical axis) of the diffracted X-ray RXR detected by the X-ray detector 2. The characteristic curve A1 is the diffraction X obtained by the X-ray detector 2 when the goniometer 5 is controlled to rotate the sample stage 6 as indicated by the arrow ω to change the incident angle of the X-ray XR. The intensity of line RXR is shown. It can be seen from the characteristic curve A1 that the intensity of the diffracted X-ray RXR is maximum when the rotation angle of the sample stage 6 is the angle ω1. That is, when the sample stage 6 is rotated by an angle ω 1 with respect to the reference horizontal plane 20 and the X-ray XR is incident on the crystal plate 10, diffraction occurs in the crystal plate 10. In other words, when the sample stage 6 is rotated by the angle ω1, the X-ray XR is incident on the cut surface 10a at the incident angle θ.

  In the example shown in FIG. 3, it is assumed that the cut surface 10 a is placed horizontally with respect to the surface 6 a of the sample table 6, that is, the cut surface 10 a is not inclined with respect to the sample table 6. In this case, the incident angle of the X-ray XR to the cut surface 10a directly corresponds to the rotation angle of the sample stage 6. For example, an angle obtained by adding / subtracting a predetermined angle to the rotation angle of the sample stage 6 is the incident angle of the X-ray XR. Therefore, the cut surface 10a can be accurately inspected based on the rotation angle of the sample stage 6 without detecting the incident angle and using it directly.

  The relationship between the rotation angle of the sample stage 6 and the intensity of the diffracted X-ray RXR is obtained by the PC 8a and displayed on the monitor 8b.

[Example of reflected laser beam measurement]
Here, a specific example of the reflected laser beam RLB detected by the laser beam receiving unit 4 will be described with reference to FIG.

  FIG. 4A is a view of the crystal plate 10, the sample stage 6, the laser beam irradiation unit 3, and the laser beam receiving unit 4 observed from the side. The laser beam irradiation unit 3 emits a laser beam LB to the quartz plate 10 (indicated by a one-dot chain line in FIG. 4A). The laser beam LB is reflected by the quartz plate 10, and the reflected laser beam RLB reflected is incident on the laser beam receiving unit 4. For example, the laser beam LB emitted from the laser beam irradiation unit 3 is incident on the quartz plate 10 at an incident angle α2, and the reflected laser beam RLB reflected on the quartz plate 10 is emitted at the emission angle α2 to receive the laser beam. Incident on part 4.

  FIG. 4B is a perspective view showing a schematic configuration of the laser beam receiving unit 4. The laser beam receiving unit 4 mainly includes a condenser lens 4a and an image sensor 4b. The reflected laser beam RLB reflected by the quartz plate 10 is incident on the condenser lens 4a, and the reflected laser beam RLB is condensed on the image sensor 4b. The image sensor 4b is configured using a CCD, a CMOS, or the like, and images the beam spot bs formed on the image sensor 4b by condensing the reflected laser beam RLB by the condenser lens 4a. Then, the imaging device 4b supplies the imaged beam spot bs data to the control unit 8 as a signal S2.

  FIG. 4C shows an example of an image G including beam spots bs1 and bs2 imaged by the image sensor 4b. The image G includes images of the beam spot bs1 and the beam spot bs2. The beam spot bs1 is approximately located at the center C of the image G, and the beam spot bs2 is shifted from the center C by a distance L. Thus, the position of the imaged beam spot is shifted from the position where the reflected laser beam RLB is reflected on the cut surface 10a of the quartz plate 10 (in other words, the position where the laser beam RB is incident on the cut surface 10a). This is because they are different. Further, the position where the reflected laser beam RLB is reflected is different in that the angle of the cut surface 10a with respect to the reference horizontal plane 20 (ie, “cut surface actual angle”) is changed by the rotation of the sample stage 6. This is because. Therefore, the distance L corresponds to the difference between the actual cut surface angle when the beam spot bs1 is imaged and the actual cut surface angle when the beam spot bs2 is imaged.

  For example, a beam spot formed when the cut surface 10 a of the crystal plate 10 is horizontal with respect to the reference horizontal plane 20 can be displayed at the center (origin) C of the image G. In this case, since the beam spot bs1 shown in FIG. 4C is located at the origin C, the beam spot bs1 is located when the cut surface 10a of the crystal plate 10 is in a horizontal position with respect to the reference horizontal plane 20. The image is taken. In the image G, the distance L between the beam spot bs1 and the beam spot bs2, in other words, the distance L between the origin C and the center point of the beam spot bs2 corresponds to the actual cut surface angle when the beam spot bs2 is imaged. To do.

  Here, the PC 8a described above obtains the position of the imaged beam spot based on the signal S2 supplied from the laser beam receiving unit 4. For example, the PC 8a obtains the coordinates of the beam spot and the distance at which the center of the beam spot is away from the origin C in the coordinates with the center C as the origin in FIG. And PC8a calculates the cut surface real angle of the cut surface 10a of the crystal plate 10 based on the information of these beam spots. Thus, the control part 8 which has PC8a functions as a cut surface real angle detection means. Note that the image G including the captured beam spot can be displayed on the monitor 8b.

[Cut surface inspection method]
Below, the cut surface inspection method which concerns on a present Example performed by the cut surface inspection apparatus 100 mentioned above is demonstrated.

(Rotation angle correction method)
The rotation angle correction method performed in the cut surface inspection method according to the present embodiment will be described with reference to FIG.

  First, the reason why the laser beam LB is applied to the crystal plate 10 in the cut surface inspection apparatus 100 according to the present embodiment will be described with reference to FIG. FIG. 5A is a view of the crystal plate 10 and the sample stage 6 observed from the side. As shown in the figure, since the dust 15 is sandwiched between the sample stage 6 and the crystal plate 10, the cut surface 10 a of the crystal plate 10 is inclined with respect to the sample stage 6. In other words, the crystal plate 10 is not placed horizontally with respect to the surface 6 a of the sample stage 6. In this case, the cut surface 10a is inclined with respect to the surface 6a of the sample stage 6 by an angle β. The phenomenon in which the cut surface 10 a is inclined with respect to the sample stage 6 often occurs particularly when the crystal plate 10 is surface-supported on the sample stage 6.

  As described above, the evaluation of the cut surface 10a of the crystal plate 10 is that the cut surface 10a is placed horizontally on the surface 6a of the sample stage 6, in other words, the angle of the cut surface 10a with respect to the reference horizontal plane 20 and the reference Assuming that the angle of the sample table 6 with respect to the horizontal plane 20 is the same, the rotation angle of the sample table 6 is related to the incident angle of the X-ray XR to the cut surface 10a, and the rotation angle is set instead of the incident angle. It is done using. For example, as described with reference to FIG. 3, the crystal plate 10 diffracted at the rotation angle ω <b> 1 is diffracted at the incident angle θ, and thus the crystal plate 10 is suitably cut. The cut surface 10a is evaluated by relating the rotation angle and the incident angle. However, when the cut surface 10a is inclined with respect to the sample table 6, the rotation angle of the sample table 6 is different from the actual cut surface angle of the cut surface 10a. In the case where they are the same, there is a deviation from the relationship between the incident angle and the rotation angle.

  That is, even if the rotation angle of the sample table 6 is the same, the incident angle of the X-ray XR incident on the cut surface 10a varies depending on the angle at which the cut surface 10a is inclined with respect to the sample table 6 or the like. End up. In other words, even if the same crystal plate 10 is used, the angle of incidence of the X-ray XR on the crystal plate 10 changes depending on the orientation with respect to the sample table 6, so the rotation angle of the sample table 6 when diffraction occurs also differs. End up. From the above, when the crystal plate 10 is surface-supported on the sample stage 6, it is preferable to evaluate the cut surface 10a based only on the rotation angle without considering the relationship between the rotation angle and the actual cut surface angle. I can say no.

  Therefore, in the cut surface inspection apparatus 100 according to the present embodiment, the rotation angle of the sample table 6 is corrected using the actual cut surface angle of the cut surface 10a, and the cut surface 10a is evaluated based on the corrected rotation angle. Here, a specific method of correcting the rotation angle will be described with reference to FIG.

  FIG. 5B is a diagram in which the crystal plate 10, the sample stage 6, the X-ray source 1, the X-ray detector 2, the laser beam irradiation unit 3, and the laser beam receiving unit 4 are observed from the side. It is. Also in this case, it is assumed that dust 15 is sandwiched between the sample table 6 and the cut surface 10a, and the cut surface 10a is inclined by an angle β with respect to the surface 6a of the sample table 6. First, the laser beam LB is irradiated to the cut surface 10 a from the laser beam irradiation unit 3, and the reflected laser beam RLB reflected by the cut surface 10 a is detected by the laser beam light receiving unit 4. And PC8a calculates | requires a cut surface real angle based on signal S2 corresponding to the beam spot formed in the image pick-up element 4b of the laser beam light-receiving part 4. FIG. In this case, the actual cut surface angle is an angle γ1 (γ1> γ2).

  Next, the PC 8a corrects the rotation angle γ2 of the sample stage 6 (an angle corresponding to the signal S3 supplied to the goniometer 5) using the obtained cut surface actual angle γ1. Specifically, the PC 8a subtracts the rotation angle γ2 from the cut surface actual angle γ1 to obtain an angle β (β = γ1−γ2) where the rotation angle γ2 is deviated from the cut surface actual angle γ1, and sets the rotation angle γ2. On the other hand, correction for adding the angle β is performed. That is, the PC 8a performs correction to match the rotation angle of the sample stage 6 with the actual cut surface angle. Then, the PC 8a obtains the relationship between the corrected rotation angle and the diffraction X-ray RXR, and evaluates the cut surface 10a based on the rotation angle when the intensity of the diffraction X-ray RXR becomes maximum. As described above, the PC 8a functions as a correction unit.

  The correction of the rotation angle described above does not actually rotate the sample table 6 by the angle to be corrected, that is, does not physically rotate the sample table 6 but the relationship with the intensity of the diffracted X-ray RXR. This means that the corrected rotation angle is used when obtaining. Therefore, the rotation angle when the intensity of the diffracted X-ray RXR is maximized, that is, the rotation angle used when the cut surface 10a is evaluated is a corrected rotation angle, and the intensity of the diffracted X-ray RXR is maximized. The actual rotation angle of the sample stage 6 is different from the corrected rotation angle.

  As shown in FIG. 5C, the correction of the rotation angle described above is such that the sample table 6 is horizontal with the cut surface 10a (that is, the dust 15 is not sandwiched between the sample table 6 and the cut surface 10a). Thus, as shown by the arrow D, it is synonymous with rotating the sample stage 6 by an angle β. Therefore, the corrected rotation angle of the sample stage 6 is such that no dust 15 is sandwiched between the sample stage 6 and the cut surface 10a, that is, the surface 6a and the cut surface 10a of the sample stage 6 are horizontal. The rotation angle at. Thereby, the relationship between the corrected rotation angle and the incident angle coincides with the relationship between the incident angle and the rotation angle when the rotation angle and the cut surface actual angle are the same. Therefore, by using the corrected rotation angle, the cut surface 10a can be accurately evaluated regardless of the orientation of the crystal plate 10 with respect to the sample stage 6. That is, the cut surface inspection apparatus 100 can accurately evaluate the cut surface 10a by appropriately dealing with a problem caused by the surface support even when the crystal plate 10 is surface-supported by the sample stage 6.

  The cut surface inspection apparatus 100 according to the present embodiment can correct the rotation angle of the sample stage 6 at the start of measurement on the cut surface 10a of the crystal plate 10. Specifically, the cut surface inspection apparatus 100 places the crystal plate 10 as the object to be measured on the sample stage 6 and samples the sample at a predetermined rotation angle (hereinafter referred to as “measurement start rotation angle”) for starting measurement. With the table 6 fixed, the actual cut surface angle of the crystal plate 10 is obtained based on the laser beam irradiation unit 3 and the laser beam light receiving unit 4, and the measurement start rotation angle is corrected using the actual cut surface angle. After performing such correction, the cut surface inspection apparatus 100 evaluates the cut surface 10a based on the corrected rotation angle of the sample table 6 while rotating the sample table 6 from the measurement start rotation angle.

(Cut surface inspection method based on the corrected rotation angle)
Next, a cut surface inspection method performed based on the corrected rotation angle will be described with reference to FIG.

  FIG. 6 shows an example of the relationship between the rotation angle of the sample table 6 and the intensity of the diffracted X-ray RXR when the cut surface 10a shown in FIG. 5 is inclined with respect to the sample table 6 by an angle β. FIG. The characteristic curve A1 indicated by the solid line is the relationship between the true rotation angle of the sample stage 6 (the rotation angle corresponding to the control signal S3 supplied from the PC 8a to the goniometer 5) and the intensity of the diffracted X-ray RXR, that is, not corrected. The relationship between the rotation angle of the state and the intensity of the diffracted X-ray RXR is shown for comparison.

  As described above, the cut surface inspection apparatus 100 determines the actual cut surface angle using the laser beam irradiation unit 3 and the laser beam light receiving unit 4 in a state where the sample stage 6 is fixed at the measurement start rotation angle. In this case, it is measured that the measurement start rotation angle γ2a of the sample stage 6 is shifted by an angle β from the measured cut surface actual angle. Therefore, the cut surface inspection apparatus 100 corrects the angle γ2b (γ2b = γ2a + β) obtained by adding the angle β to the measurement start rotation angle γ2a as a new measurement start rotation angle. A characteristic curve A2 indicated by a broken line indicates a relationship between the corrected rotation angle and the intensity of the diffracted X-ray RXR obtained by performing such correction. This characteristic curve A2 is obtained by translating the characteristic curve A1 by an angle β. That is, when the rotation angle is not corrected, the intensity of the diffracted X-ray RXR becomes maximum at the rotation angle ω2, but when the rotation angle is corrected, the intensity of the diffracted X-ray RXR is maximum at the rotation angle ω3. Thus, the rotation angle ω3 is shifted by an angle β with respect to the rotation angle ω2. The cut surface inspection apparatus 100 evaluates the cut surface 10a using the rotation angle ω3. The rotation angle ω3 is a rotation angle when the cut surface 10a is not inclined with respect to the sample table 6, that is, the surface 6a of the sample table 6 and the cut surface 10a are horizontal. By using this rotation angle ω3, the cut surface 10a can be accurately evaluated.

  As described above, the cut surface inspection apparatus 100 according to the present embodiment uses the laser beam irradiation unit 3 and the laser beam receiving unit 4 to obtain the cut surface actual angle of the cut surface 10a with respect to the reference horizontal plane 20, and the cut surface actual angle. Is used to correct the rotation angle of the sample stage 6. Therefore, the cut surface inspection apparatus 100 can accurately evaluate the cut surface 10a regardless of the posture of the cut surface 10a with respect to the sample table 6 by using the corrected rotation angle.

  Thereby, the cut surface inspection apparatus 100 according to the present embodiment can accurately evaluate the cut surface 10a even when the crystal plate 10 is surface-supported by the sample stage 6. That is, the cut surface inspection apparatus 100 can accurately evaluate the cut surface 6a without performing measurement by supporting the crystal plate 10 on the sample stage 6 (for example, supporting three points). As a result, when a large-sized quartz plate 10 (for example, a quartz plate 10 of 1 inch or more) is point-supported on the sample stage 6, it may be warped due to its own weight and cannot be accurately measured. Since the apparatus 100 can appropriately cope with the trouble caused by the surface support, it is possible to accurately evaluate the cut surface 10a by supporting the large-sized quartz crystal plate 10 on the surface. Therefore, since the cut surface inspection apparatus 100 can evaluate the cut surface 10a at a time with respect to the large-sized quartz crystal plate 10, it is possible to shorten the time required for the evaluation of the cut surface 10a of the quartz crystal plate 10. It becomes. Furthermore, by supporting the quartz plate 10 on the surface, multipoint measurement can be easily performed by repositioning the sample stage 6.

[Cut surface inspection process]
Next, the cut surface inspection processing according to the present embodiment will be described with reference to the flowchart of FIG. The cut surface inspection process is mainly executed by the PC 8a in the cut surface inspection apparatus 100.

  First, in step S <b> 11, the crystal plate 10 serving as a sample is placed on the sample table 6. Then, the process proceeds to step S <b> 12, and the PC 8 a supplies the control signal S <b> 3 to the goniometer 5 and moves the sample stage 6 to a position where measurement is started by the goniometer 5. That is, the PC 8a sets the rotation angle of the sample stage 6 to the measurement start rotation angle. Then, the process proceeds to step S13.

  In step S13, the PC 8a measures the actual cut surface angle of the cut surface 10a of the crystal plate 10 when the sample stage 6 is set to the measurement start rotation angle. Specifically, the laser beam irradiation unit 3 irradiates the cut surface 10a with the laser beam LB, and the laser beam receiving unit 4 images a beam spot formed by the reflected laser beam LB reflected by the cut surface 10a. A signal S2 corresponding to the imaged beam spot is supplied to the PC 8a. And PC8a acquires this signal S2, and calculates | requires the cut surface real angle of the cut surface 10a based on the position of the imaged beam spot. Then, the process proceeds to step S14.

  In step S14, the PC 8a corrects the rotation angle of the sample stage 6 using the actual cut surface angle obtained in step S13. Specifically, the PC 8a obtains an angle at which the rotation angle is deviated from the actual cut surface angle, and performs correction for adding / subtracting the deviated angle to the rotation angle. In other words, correction is performed such that the rotation angle obtained by matching the measurement start rotation angle with the cut surface actual angle is set as a new measurement start rotation angle. Then, the process proceeds to step S15.

  In step S15, the PC 8a measures the intensity of the diffracted X-ray RXR based on the signal S1 supplied from the X-ray detector 2 while controlling the goniometer 5 and rotating the sample stage 6. Specifically, a graph showing the relationship between the corrected rotation angle and the intensity of the diffracted X-ray RXR as shown in FIG. 6 is created. Then, the process proceeds to step S16.

  In step S16, the PC 8a evaluates the cut surface 10a of the crystal plate 10 based on the rotation angle of the sample stage 6 when the intensity of the diffracted X-ray RXR is maximized. Specifically, the PC 8a obtains the maximum intensity of the diffracted X-ray RXR based on the graph showing the relationship between the corrected rotation angle and the intensity of the diffracted X-ray RXR obtained in step S15. The rotation angle of the sample stage 6 is obtained. The PC 8a evaluates the cut surface 10a by comparing the obtained rotation angle with the above-described reference rotation angle. When the above process ends, the process exits the flow.

  By executing the cut surface inspection process as described above, even if the cut surface 10a is inclined with respect to the sample table 6 due to dust or the like being sandwiched between the sample table 6 and the crystal plate 10, the corrected sample Based on the rotation angle of the table 6, it is possible to appropriately evaluate the cut surface 10a.

[Modification]
Next, a cut surface inspection apparatus 101 according to a modification of the present invention will be described with reference to FIG.

  FIG. 8 is a block diagram showing a schematic configuration of a cut surface inspection apparatus 101 according to a modification. FIG. 8 shows only an optical system (consisting of an X-ray source 1, an X-ray detector 2, a laser beam irradiation unit 3, a laser beam receiving unit 4, and the like) in the cut surface inspection apparatus 101, from the side. The observed figure is shown. In addition, the same code | symbol is attached | subjected about the same component as the above-mentioned cut surface inspection apparatus 100, and the description is abbreviate | omitted.

  The cut surface inspection apparatus 101 according to the modification is different from the cut surface inspection apparatus 100 described above in terms of the position where the laser beam light receiving unit 4 is provided and the optical path of the reflected laser beam RLB incident on the laser beam light receiving unit 4. Different. Specifically, in the cut surface inspection apparatus 101, the laser beam receiving unit 4 is provided below the crystal plate 1. Therefore, in the cut surface inspection apparatus 101, the optical path of the reflected laser beam RLB reflected by the quartz plate 1 is changed using the mirrors 9a and 9b and is incident on the laser beam receiving unit 4 disposed below.

  As described above, the cut surface inspection apparatus 100 and the cut surface inspection apparatus 101 according to the modification have different arrangement positions of the laser beam receiving unit 4 in the cut surface inspection apparatus 101 according to the modification. This is because other constituent elements (not shown) are disposed at the position where the laser beam receiving unit 4 is provided in 100. In addition, the change of the arrangement position of the component in the cut surface inspection apparatus is not limited to the laser beam receiving unit 4, and the arrangement position of the X-ray source 1, the X-ray detector 2, the laser beam irradiation unit 3, and the like is also changed. can do. Further, when the arrangement position of the component is changed, it is necessary to change an optical path such as an X-ray or a laser beam using a mirror or the like.

It is a figure which shows schematic structure of the cut surface inspection apparatus which concerns on the Example of this invention. It is a figure for demonstrating the rotation angle of a sample stand. It is a figure which shows the example of a measurement of a diffraction X ray. It is a figure which shows the example of a measurement of a reflected laser beam. It is a figure for demonstrating the correction method of the rotation angle of a sample stand. It is a figure which shows the relationship between the rotation angle after correction | amendment, and the intensity | strength of a diffraction X-ray. It is a flowchart which shows the cut surface inspection process which concerns on the Example of this invention. It is a figure which shows schematic structure of the cut surface inspection apparatus which concerns on the modification of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 X-ray source 2 X-ray detector 3 Laser beam irradiation part 4 Laser beam light-receiving part 5 Goniometer 6 Sample stand 8 Control part 8a PC (personal computer)
DESCRIPTION OF SYMBOLS 10 Crystal plate 10a Cut surface 100, 101 Cut surface inspection apparatus

Claims (6)

A sample stage for supporting a sample cut at a predetermined angle with respect to the crystal lattice plane;
A rotating means for rotating the sample stage around an axis horizontal to the cut surface of the sample;
X-ray irradiation means for irradiating the sample with X-rays;
X-ray detection means for detecting a diffracted X-ray of the X-ray diffracted by the sample;
Laser beam irradiation means for irradiating the sample with a laser beam;
A reflected laser beam detecting means that receives a reflected laser beam of the laser beam reflected by the sample and detects the reflected laser beam;
Cut surface actual angle detecting means for detecting a cut surface actual angle of the cut surface with respect to a reference horizontal plane based on the detected reflected laser beam;
Correction means for correcting the rotation angle of the sample stage with respect to the reference horizontal plane using the cut surface actual angle;
A cut surface inspection apparatus comprising: an evaluation unit that evaluates the cut surface based on the corrected rotation angle and the detected diffraction X-ray.   2. The cut surface inspection according to claim 1, wherein the evaluation unit evaluates the cut surface based on the corrected rotation angle when the intensity of the detected diffraction X-ray is maximized. 3. apparatus.   The cut surface inspection apparatus according to claim 1, wherein the sample stage supports the sample on the cut surface.   4. The cut surface actual angle detection unit according to claim 1, wherein the cut surface actual angle detection unit detects the cut surface actual angle based on a position of a beam spot formed by the reflected laser beam. 5. Cut surface inspection device.   The cut surface inspection apparatus according to claim 1, wherein the correction unit corrects the rotation angle when starting the evaluation of the cut surface. An inspection apparatus comprising a sample stage for supporting a sample cut at a predetermined angle with respect to the crystal lattice plane, and a rotating means for rotating the sample stage about an axis parallel to the cut surface of the sample was used. A cut surface inspection method,
An X-ray irradiation step of irradiating the sample with X-rays;
An X-ray detection step of detecting a diffracted X-ray of the X-ray diffracted by the sample;
A laser beam irradiation step of irradiating the sample with a laser beam;
A reflected laser beam detecting step in which a reflected laser beam of the laser beam reflected by the sample is incident and the reflected laser beam is detected;
A cut surface actual angle detecting step for detecting a cut surface actual angle of the cut surface with respect to a reference horizontal plane based on the detected reflected laser beam;
A correction step of correcting the rotation angle of the sample stage with respect to the reference horizontal plane using the cut surface actual angle;
An evaluation step of evaluating the cut surface based on the corrected rotation angle and the detected diffraction X-ray, and a cut surface inspection method.

Images