JP2006275901A - Device and method for crystal evaluation - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for crystal evaluation capable of efficiently acquiring many data related to a crystal structure, and method for crystal evaluation. <P>SOLUTION: The device 100 for crystal evaluation includes a sample stand 10 for mounting a sample 32, an X-ray source 12 for irradiating the sample 32 placed on the sample stand 10 with X rays, an X-ray detection part 14 for detecting diffracted X rays emitted by irradiating the sample 32, a laser light source 16 for irradiating the sample 32 with a laser beam, a spectroscope 18 for spectrally diffracting Raman scattered light scattered by irradiating the sample 32 and a light detecting part 20 for detecting the intensity of the spectrum spectrally diffracted by the spectroscope 18. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a crystal evaluation apparatus and a crystal evaluation method. In particular, the present invention relates to a crystal evaluation apparatus and a crystal evaluation method including an X-ray diffraction apparatus.

  In order to evaluate the structure of a crystalline thin film on a substrate applied to an electronic device or the like, an X-ray diffraction apparatus is most widely used. According to the X-ray diffractometer, information on the crystal lattice constant can be obtained, and by analyzing this information, knowledge on the crystal system, crystallinity, and orientation distribution of the crystal can be obtained.

However, along with the downsizing and increasing capacity of electronic devices and the like, in addition to the above-described information on crystals, methods for obtaining information on more detailed structures in crystals have been developed. An efficient acquisition method is desired.
JP 2003-215069 A

  An object of the present invention is to provide a crystal evaluation apparatus and a crystal evaluation method capable of efficiently acquiring more information on a crystal structure.

The crystal evaluation apparatus according to the present invention includes:
A sample stage for placing the sample;
An X-ray source for irradiating the sample placed on the sample stage with X-rays;
An X-ray detector that detects diffracted X-rays generated by irradiating the sample;
A laser light source for irradiating the sample with laser light;
A spectroscope for spectroscopic analysis of Raman scattered light scattered by irradiating the sample;
A light detection unit for detecting the intensity of the spectrum dispersed by the spectrometer;
including.

  According to the crystal evaluation apparatus according to the present invention, Raman scattering measurement and X-ray diffraction measurement can be performed with the same apparatus, and precise crystal system identification and crystal principal axis orientation that cannot be obtained only by X-ray diffraction measurement. And the like can be obtained in a short time without destroying the sample. In addition, since Raman scattering measurement and X-ray diffraction measurement can be performed on the same sample under the same environment (temperature, humidity, etc.), Raman scattering measurement and X-ray diffraction measurement can be performed with different apparatuses. Compared with the case where it performs, a more accurate result can be obtained.

In the crystal evaluation apparatus according to the present invention,
A lens for condensing laser light from the laser light source on the surface of the sample;
The X-ray source and the X-ray detection unit may be rotatably provided with the focal point of the lens as a rotation center.

  As a result, X-ray diffraction measurement can be performed at substantially the same position as the Raman scattering measurement on the sample surface.

In the crystal evaluation apparatus according to the present invention,
A lens for condensing laser light from the laser light source;
The X-ray source can irradiate at least the focal position of the lens with the X-ray. Thereby, the positioning of the sample of a Raman scattering measurement and a X-ray diffraction measurement can be performed simultaneously using the laser beam for a Raman scattering measurement.

In the crystal evaluation apparatus according to the present invention,
A lens for condensing the laser light from the laser light source;
A display unit configured to determine whether the focal point of the lens is coincident with the surface of the sample, and displaying an image of the sample irradiated with laser light on the sample;

  Thereby, the operator of the crystal evaluation apparatus can easily determine whether or not the focal point of the lens coincides with the surface of the sample by visually recognizing the display unit.

In the crystal evaluation apparatus according to the present invention,
It may further include an intensity detection unit that detects the intensity of scattered light generated by irradiating the sample with laser light.

In the crystal evaluation apparatus according to the present invention,
The apparatus may further include a sample stage position determining unit that determines the position of the sample stage based on the intensity detected by the intensity detecting unit.

In the crystal evaluation apparatus according to the present invention,
The laser beam may be emitted from the laser light source. Thereby, the crystal evaluation apparatus can use the same laser light source as the laser light source used for the Raman scattering measurement for the positioning of the sample.

The crystal evaluation method according to the present invention includes:
(A) irradiating a sample placed on the sample stage with laser light from a laser light source via a lens;
(B) detecting whether or not the focus of the lens coincides with the surface of the sample by detecting scattered light generated by irradiating the sample with laser light;
(C) moving the position of the sample stage when it is determined that the focal point of the lens does not coincide with the surface of the sample;
(D) performing Raman scattering measurement by irradiating the sample with laser light from the laser light source when it is determined that the focal point of the lens coincides with the surface of the sample;
(E) performing X-ray diffraction measurement by irradiating the sample with X-rays when the focal point of the lens coincides with the surface of the sample;
including.

In the crystal evaluation method according to the present invention,
In the step (b), an image of the sample irradiated with laser light can be detected, and it can be determined based on the detected image whether the focal point of the lens coincides with the surface of the sample.

In the crystal evaluation method according to the present invention,
In the step (b), it is possible to detect the intensity of the scattered light and determine whether or not the focus of the lens coincides with the surface of the sample based on the detected intensity of the scattered light.

In the crystal evaluation method according to the present invention,
Before the step (c), further comprising the step of calculating the position of the surface of the sample based on the intensity of the scattered light detected in the step (b);
In the step (c), the position of the sample stage can be moved so that the calculated position of the surface of the sample matches the position of the focal point of the lens.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1. Crystal Evaluation Apparatus The crystal evaluation apparatus 100 according to this embodiment performs Raman scattering measurement and X-ray diffraction measurement of a sample. According to the Raman scattering measurement, information on the vibration state of atoms in the sample can be obtained. The information on the vibrational state of the atoms in the sample is, for example, information on the ordered state of the atomic arrangement constituting the crystal, deviation from the stoichiometric ratio, information on the position of defects, and plane orientation. On the other hand, according to the X-ray diffraction measurement, information on the crystal lattice constant can be obtained. By analyzing both the information obtained from the Raman scattering measurement and the information obtained from the X-ray diffraction measurement, the crystal structure can be examined in detail.

  FIG. 1 is a block diagram showing a main functional configuration of the crystal evaluation apparatus 100 according to the present embodiment. The crystal evaluation apparatus 100 includes a measurement unit 110, a display unit 42, an input unit 44, a measurement control unit 46, a storage unit 48, and a processing unit 50.

  The measuring unit 110 measures, for example, a sample 32 made of crystals by an X-ray diffraction method and a Raman scattering spectroscopic analysis method. The detailed configuration of the measurement unit 110 will be described later.

  The measurement control unit 46 performs control for causing the measurement unit 110 to measure the sample. The processing unit 50 processes the measurement value measured by the measurement unit 110 and sends the processing result to the storage unit 48 or the display unit 42. The storage unit 48 serves as a work area for realizing various processing functions of the processing unit 50 and the measurement control unit 46 in addition to storing various setting data (for example, measurement control data). Can be realized by hardware such as RAM, ROM, optical disk, magneto-optical disk. The storage unit 48 may store a program for causing each unit of the crystal evaluation apparatus 100 to function. The crystal evaluation apparatus 100 can read the program stored in the storage unit 48 and realize the functions of each unit of the crystal evaluation apparatus 100. Moreover, it replaces with the memory | storage part 48, and also implement | achieves the function of each part of the crystal | crystallization evaluation apparatus 100 mentioned above by downloading the program etc. for implement | achieving each function mentioned above from a host apparatus etc. via a transmission line. Is possible.

  The display unit 42 displays an image detected by the image detection unit 24 of the measurement unit 110 described later. The display unit 42 may output an image of the setting state, operating state, measurement result, or the like of the crystal evaluation apparatus 100, and the function can be realized by known hardware such as a CRT, LCD, touch panel display.

  The input unit 44 is for an operator of the crystal evaluation apparatus 100 to input various setting data and operation data, and the function can be realized by hardware such as a keyboard, operation buttons, and a touch panel display.

  Next, details of the measurement unit 110 will be described. FIG. 2 is a diagram illustrating a detailed configuration of the measurement unit 110 according to the present embodiment. The measurement unit 110 has a function as a Raman scattering measurement device and a function as an X-ray diffraction device. As shown in FIG. 2, the measurement unit 110 includes, for example, a sample stage 10 on which a crystal sample 32 is placed, an X-ray source 12 and an X-ray detection unit 14 that perform X-ray diffraction measurement, and Raman scattering measurement. A laser light source 16, a spectroscope 18, a light detection unit 20, a first mirror 25, and an objective lens 22.

  First, among the functions of the measurement unit 110, functions for performing Raman scattering measurement will be described. In the present embodiment, the Raman scattering measurement is performed in a backscattering arrangement. The laser light source 16 emits laser light. The laser light source 16 provided in the measurement unit 110 may be a light emitting element or an optical transmission medium such as an optical fiber. The emitted laser light is reflected by the first mirror 25 and irradiates the surface of the sample 32 through the objective lens 22. The first mirror 25 is disposed in a state inclined by 45 degrees with respect to the optical path of the laser light, and can be directed to the direction of the sample 32 placed on the sample stage 10 by converting the optical path of the laser light by 90 degrees. The objective lens 22 condenses the laser light directed onto the sample 32. Thereby, the Raman scattering efficiency can be increased. The condensed laser light is emitted to the third mirror 27 via the objective lens 22 as the Raman scattered light generated by being irradiated onto the sample 32. The third mirror 27 is a half mirror, and guides the Raman scattered light toward the spectroscope 18. The third mirror 27 is arranged in a state inclined by 45 degrees with respect to the optical path of the laser light, and can convert the optical path of the Raman scattered light by 90 degrees and direct it in the direction of the spectrometer 18. The spectroscope 18 splits the Raman scattered light into a plurality of spectra and sends it to the light detection unit 20. The light detection unit 20 detects the intensity of the spectrum sent from the spectroscope 18. The light detection unit 20 is preferably multi-channel in order to detect a plurality of spectra simultaneously. As the light detection unit 20, for example, a CCD is used. The light detection unit 20 sends information indicating the intensity of the detected spectrum to the processing unit 50.

  Next, the function of performing X-ray diffraction measurement will be described. The X-ray source 12 irradiates the position of the focal point 30 of the objective lens 22 with X-rays. Thereby, the crystal evaluation apparatus 100 can perform X-ray diffraction measurement at the same position on the sample 32 as the position where Raman scattering spectroscopic measurement is performed, and can perform highly accurate crystal evaluation.

  The X-ray detector 14 detects diffracted X-rays generated by irradiating the sample 32. The X-ray detector 14 and the X-ray source 12 have a goniometer structure that can rotate independently of each other about the rotation center. The X-ray detector 14 and the X-ray source 12 are provided such that the center of rotation coincides with the focal point 30 of the objective lens 22. X-ray irradiation by the X-ray source 12 and detection of diffracted X-rays by the X-ray detector 14 are sequentially performed while changing the diffraction angle by a goniometer.

  The measurement unit 110 further includes an image detection unit 24, a sample stage drive unit 11 that drives the sample stage 10, a second mirror 26, and a mirror drive unit 23 that drives the second mirror 26. The second mirror 26 has a function of guiding Raman scattered light to the image detection unit 24. Specifically, the second mirror 26 is arranged in a 45 ° tilted state with respect to the Raman scattered light from the third mirror 27, and the optical path of the Raman scattered light is converted by 90 ° in the direction of the image detection unit 24. Can be directed. The second mirror 26 is provided between the third mirror 27 and the spectroscope 18 so as to be movable in the vertical direction in FIG. 2. When performing the Raman scattering measurement, the second mirror 26 is at a position (upward) that does not block the Raman scattered light. Moving.

  The image detection unit 24 receives the Raman scattered light generated from the sample 32 to send an image of the sample 32 to the display unit 42. The operator of the crystal evaluation apparatus 100 can determine whether or not the focal point 30 of the objective lens 22 coincides with the surface of the sample 32 by checking the display unit 42. An operator of the crystal evaluation apparatus 100 can input information regarding the position of the sample stage 10 from the input unit 44. The sample stage drive unit 11 can move the position of the sample stage 10 in the x, y, or z axis direction according to the information regarding the position of the sample stage 10 input from the input unit 44.

2. Crystal Evaluation Method Next, a crystal evaluation method according to this embodiment will be described. FIG. 3 is a flowchart showing the operation of the crystal evaluation apparatus according to this embodiment.

  First, the operator of the crystal evaluation apparatus 100 places the sample 32 on the sample stage 10 (step S100). Next, the laser light source 16 irradiates the sample 32 with laser light through the objective lens 22 (step S102). At this time, the second mirror 26 is disposed at a position where the Raman scattered light from the sample 32 can be guided to the image detection unit 24.

  Next, the operator of the crystal evaluation apparatus 100 confirms the image of the surface of the sample 32 detected by the image detection unit 24 and determines whether or not the focus of the objective lens 22 coincides with the surface of the sample 32 ( Step S104). Specifically, the operator of the crystal evaluation apparatus 100 checks whether or not the focus of the objective lens 22 coincides with the surface of the sample 32 by checking the laser beam diameter on the sample 32 displayed on the display unit 42. Judging. It can be said that the focal point of the objective lens 22 coincides with the surface of the sample 32 when the laser beam diameter is minimum. When the input unit 44 receives information indicating that the operator has determined that the focal point of the objective lens 22 is coincident with the surface of the sample 32, the operation of the crystal evaluation apparatus 100 jumps to step S112.

  On the other hand, when the operator determines that the focal point of the objective lens 22 does not coincide with the surface of the sample 32, the operator changes the height of the sample stage 10 (step S106).

  Next, the laser light source 16 irradiates the sample 32 with laser light (step S108). Next, the operator of the crystal evaluation apparatus 100 confirms the image of the surface of the sample 32 detected by the image detection unit 24 and determines whether or not the focus of the objective lens 22 coincides with the surface of the sample 32 ( Step S110). The crystal evaluation apparatus 100 repeats the operations in steps S106 to S110 until the operator determines that the focal point of the objective lens 22 coincides with the surface of the sample 32.

  As described above, the crystal evaluation apparatus 100 irradiates the sample 32 with the laser light emitted from the laser light source 16 used for the Raman scattering measurement in advance and confirms the image, whereby the surface of the sample 32 is observed on the objective lens 22. Can be adjusted to the focus position. This makes it possible to perform highly accurate Raman scattering measurement and X-ray diffraction measurement.

  In step S110 and step S104, when the input unit 44 receives information indicating that the operator has determined that the focus of the objective lens 22 is coincident with the surface of the sample 32, the crystal evaluation apparatus 100 performs the Raman scattering measurement. Then, X-ray diffraction measurement is performed (steps S112 and S114). Here, the crystal evaluation apparatus 100 moves the position of the second mirror 26 so that the Raman scattered light enters the spectrometer 18 before performing the Raman scattering measurement.

  Usually, since the Raman scattering measurement and the X-ray diffraction measurement are performed by different apparatuses, after performing one measurement, the sample has to be remounted on the apparatus in order to perform the other measurement. At this time, not only the time burden, but also the risk of sample breakage, changes in the sample state due to temperature changes, and the like occurred. Therefore, according to the crystal evaluation apparatus 100 according to the present embodiment, the Raman scattering measurement and the X-ray diffraction measurement can be performed at the same time, so that the risk of sample breakage or the like can be reduced in a shorter time. Further, according to the crystal evaluation apparatus 100 according to the present embodiment, X-ray diffraction measurement can be performed at the same position on the surface of the sample 32 as the position where Raman scattering measurement is performed.

  Furthermore, according to the crystal evaluation apparatus 100, even when measuring a plurality of regions on the surface of the sample 32, after measuring one region by the above-described operation, the sample stage 10 is moved in the x or y axis direction. By performing the above-described operation again, crystal evaluation can be performed with high accuracy in a short time.

3. Modified Example Next, a modified example of the crystal evaluation apparatus according to the present embodiment will be described. The crystal evaluation apparatus 200 according to the modified example determines the position of the sample stage 10 while checking the image of the sample 32 while the operator determines the position of the sample stage 10 based on the intensity of Raman scattered light. Different from the crystal evaluation apparatus 100.

  FIG. 4 is a block diagram showing a functional configuration of the crystal evaluation apparatus 200 according to the modification. The crystal evaluation apparatus 200 further includes an intensity detection unit 28 and a position determination unit 29 in place of the image detection unit 24. The intensity detection unit 28 detects the intensity of the scattered light generated by irradiating the sample 32 with the laser light and sends it to the position determination unit 29. The position determination unit 29 determines the position of the sample stage 10 based on the information indicating the intensity received from the intensity detection unit 28.

  Next, a crystal evaluation method according to a modification will be described with reference to FIG. FIG. 5 is a flowchart showing the operation of the crystal evaluation apparatus 200.

  First, the operator of the crystal evaluation apparatus 200 places the sample 32 on the sample stage 10 (step S200). Next, the laser light source 16 irradiates the sample 32 with laser light through the objective lens 22 (step S202).

  Next, the intensity detection unit 28 detects the intensity of scattered light generated by irradiating the sample 32 with laser light (step S204).

  Next, the position determination unit 29 determines the position of the sample stage 10 based on the intensity detected by the intensity detection unit 28 (step S206). Specifically, the position determination unit 29 calculates the position of the surface of the sample 32 based on the intensity detected by the intensity detection unit 28, and an appropriate sample table is calculated from the position and the current position of the sample table 10. 10 positions are determined. Since the intensity of the scattered light is higher as the position of the focal point 30 is closer to the surface of the sample 32, the crystal evaluation apparatus 200, for example, previously determines the distance between the position of the focal point 30 and the surface of the sample 32 and the intensity of the scattered light. The relational expression is stored for each sample, and the position determination unit 29 can determine the position of the sample stage 10 using the relational expression.

  Next, the sample stage drive unit 11 moves the sample stage 10 to the position determined by the position determination unit 29 (step S208).

  Next, the crystal evaluation apparatus 100 performs Raman scattering measurement and X-ray diffraction measurement (steps S210 and S212).

  Thus, according to the crystal evaluation apparatus 200, the position of the sample stage 10 can be determined by detecting the intensity of the scattered light based on the laser light from the laser light source 16. Thereby, alignment of the sample stage 10 can be performed simply and accurately.

  Other configurations and operations of the crystal evaluation apparatus 200 according to the modified example are the same as the configurations and operations of the crystal evaluation apparatus 100 described above, and thus description thereof is omitted.

  The present invention is not limited to the above-described embodiments, and various modifications can be made. For example, the crystal evaluation apparatus 200 according to the modified example determines the height of the sample stage 10 by detecting the intensity of scattered light, but instead detects an image of the surface of the sample 32, An appropriate height of the sample stage 10 may be determined by image analysis. For example, the crystal evaluation apparatus 200 stores a relational expression between the laser beam diameter on the sample 32 and the distance between the surface of the specimen 32 and the focal point by image analysis, and uses the relational expression to appropriately increase the height of the sample stage 10. Can be determined.

  Further, the invention includes substantially the same configuration (for example, a configuration having the same function, method, and result, or a configuration having the same purpose and result) as the configuration described in the embodiment. In addition, the invention includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. In addition, the present invention includes a configuration that achieves the same effect as the configuration described in the embodiment or a configuration that can achieve the same object. Further, the invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

The block diagram which shows the function structure of the crystal | crystallization evaluation apparatus concerning this Embodiment. The figure which shows typically the measurement part concerning this Embodiment. The flowchart which shows the crystal | crystallization evaluation method concerning this Embodiment. The block diagram which shows the function structure of the crystal | crystallization evaluation apparatus concerning a modification. The flowchart which shows the crystal | crystallization evaluation method concerning a modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Sample stand, 12 X-ray source, 14 X-ray detection part, 16 Laser light source, 18 Spectrometer, 20 Optical detection part, 22 Objective lens, 24 Image detection part, 25 1st mirror, 26 2nd mirror, 27 Third mirror, 28 Intensity detection unit, 29 Position determination unit, 30 Focus, 32 Sample, 42 Display unit, 44 Input unit, 46 Measurement control unit, 48 Storage unit, 50 Processing unit, 100, 200 Crystal evaluation apparatus, 110 210 Measurement unit

Claims (11)

A sample stage for placing the sample;
An X-ray source for irradiating the sample placed on the sample stage with X-rays;
An X-ray detector that detects diffracted X-rays generated by irradiating the sample;
A laser light source for irradiating the sample with laser light;
A spectroscope for spectroscopic analysis of Raman scattered light scattered by irradiating the sample;
A light detection unit for detecting the intensity of the spectrum dispersed by the spectrometer;
A crystal evaluation apparatus. In claim 1,
A lens for condensing laser light from the laser light source on the surface of the sample;
The crystal evaluation apparatus, wherein the X-ray source and the X-ray detection unit are rotatably provided with the focal point of the lens as a rotation center. In claim 1 or 2,
A lens for condensing laser light from the laser light source;
The crystal evaluation apparatus, wherein the X-ray source irradiates at least a focal position of the lens with the X-ray. In any one of Claims 1 thru | or 3,
A lens for condensing the laser light from the laser light source;
A crystal evaluation apparatus, further comprising: a display unit configured to determine whether or not a focal point of the lens coincides with a surface of the sample, and displaying an image of the sample irradiated with laser light on the sample. . In any one of Claims 1 thru | or 3,
A crystal evaluation apparatus further comprising an intensity detector that detects the intensity of scattered light generated by irradiating the sample with laser light. In claim 5,
The crystal evaluation apparatus further comprising a sample stage position determination unit that determines the position of the sample stage based on the intensity detected by the intensity detection unit. In claim 5,
The crystal evaluation apparatus, wherein the laser light is emitted from the laser light source. (A) irradiating a sample placed on the sample stage with laser light from a laser light source via a lens;
(B) determining whether the focal point of the lens coincides with the surface of the sample by detecting scattered light generated by irradiating the sample with laser light;
(C) moving the position of the sample stage when it is determined that the focal point of the lens does not coincide with the surface of the sample;
(D) performing Raman scattering measurement by irradiating the sample with laser light from the laser light source when it is determined that the focal point of the lens coincides with the surface of the sample;
(E) performing X-ray diffraction measurement by irradiating the sample with X-rays when the focus of the lens coincides with the surface of the sample;
A crystal evaluation method comprising: In claim 8,
In the step (b), a crystal evaluation method for detecting an image of the sample irradiated with laser light and determining whether the focus of the lens coincides with the surface of the sample based on the detected image . In claim 8,
In the step (b), the intensity of scattered light is detected, and based on the detected intensity of scattered light, it is determined whether or not the focus of the lens coincides with the surface of the sample. In claim 10,
Before the step (c), further comprising the step of calculating the position of the surface of the sample based on the intensity of the scattered light detected in the step (b);
In the step (c), the crystal evaluation method of moving the position of the sample stage so that the calculated position of the surface of the sample coincides with the focal position of the lens.

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