JP2008261815A - Crystal orientation determination device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for easily determining a crystal orientation and a grain boundary angle of an FIM sample even by a less-informed and unexperienced worker, and to provide a device for determining a crystal orientation even for a sample difficult to determine orientation conventionally because a crystal grain size is small. <P>SOLUTION: The crystal orientation determination device comprises at least an image data fetching means of a field-ion microscope (FIM) image with respect to the crystal grain in a measured sample, a means for rotating a logical crystal orientation pole of an object crystal grain to correspond to a specific crystal orientation pole in the fetched FIM image, a means for determining crystal orientation poles l, m, n of the specific crystal orientation poles from a result of rotating operation, and a means for superimposing and displaying the FIM image and the determined crystal orientation poles l, m, n. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a crystal orientation determining apparatus used in three-dimensional atom probe (3D-AP) measurement or field ion microscope (FIM) measurement.

  Conventionally, the crystal orientation has been determined by analyzing the X-ray diffraction Kossel line pattern, electron beam diffraction channeling pattern (ECP), electron beam backscatter diffraction pattern (EBSP), and Kikuchi pattern. However, since the sample used for 3D-AP measurement and FIM measurement has a needle-like shape with a tip having a curvature of about 10 nm, the Kossel line figure and ECP and EBSP have insufficient spatial resolution or the sample surface is Since it is not a flat surface, analysis is impossible, and Kikuchi pattern analysis has been performed to determine the grain boundary angle of such a sample (Non-Patent Document 1).

  In the Kikuchi pattern analysis method, in order to determine the angle formed between two crystal grains forming a grain boundary, after processing a sample, a TEM (transmission electron microscope) is used to obtain diffraction images called Kikuchi patterns. By taking a picture of a crystal grain and analyzing its pattern, the crystal orientation of each crystal grain is determined and the angle of the grain boundary is determined. This method requires experience and knowledge for analysis, and requires about one day of work time, and it was impossible to analyze many samples in a short time.

  In addition, when the size of the crystal grain to be measured is small, the Kikuchi pattern cannot be obtained, and the crystal orientation may not be determined. Therefore, there has been a demand for a crystal orientation measuring method and apparatus that can be used by non-skilled persons in a short time or even with a sample having fine crystal grains.

J. et al. A. Veables and C.I. J. et al. Harland: Phil. Mag. , Vol. 27, p. 1193 (1973)

  In view of the above situation, the present invention provides an apparatus capable of easily determining the crystal orientation and the grain boundary angle of an FIM sample even with an operator having little knowledge and experience, and having a small crystal grain size. Thus, the present invention provides an apparatus that can determine the crystal orientation of a sample that has been difficult to determine in the past.

This invention solves the said subject, and the summary of the invention is as follows.
(1) Image data capturing means for capturing image data of field ion microscope images of crystal grains in a measurement sample, and theoretical crystal orientation poles of target crystal grains with respect to specific crystal orientation poles in the captured field ion microscope images , A means for rotating to match, a means for determining the crystal orientation pole (l, m, n) of the specific crystal orientation pole based on the result of the rotation, and the field ion microscope image determined A crystal orientation determining apparatus, comprising at least means for displaying the crystal orientation poles (l, m, n) in an overlapping manner.
(2) The crystal orientation determination device according to (1), wherein at least three crystal orientation poles (l, m, n) are displayed.
(3) Image data capturing means for capturing image data of field ion microscope images before and after field evaporation of the measurement sample, and specific crystal orientation in the field ion microscope image for each of the captured field ion microscope images Means for rotating each so that the theoretical crystal orientation pole of the target crystal grain coincides with the pole, and based on the result of the rotation, the crystal orientation pole (l, m, n) of each of the specific crystal orientation poles ) And a means for determining the crystal rotation angle between crystal grains from the crystal orientation poles (l, m, n) before and after field evaporation.
(4) Image data capturing means for capturing image data of a field ion microscope image of the surface of the measurement sample including the grain boundary, means for discriminating the grain boundary in the captured field ion microscope image, and each distinguished by the grain boundary Based on the result of the rotation operation, the means for rotating the respective crystal grains so that the theoretical crystal orientation pole of the target grain coincides with the specific crystal orientation pole in the field ion microscope image. And means for determining crystal orientation poles (l, m, n) of the specific crystal orientation poles, and crystal grains sandwiching grain boundaries based on the crystal orientation poles (l, m, n). A crystal orientation determining device comprising at least means for determining a crystal rotation angle therebetween.
(5) Image data capturing function for capturing image data of field ion microscope images of crystal grains in a measurement sample into a computer, and the theory of target crystal grains with respect to specific crystal orientation poles in the captured field ion microscope images A function of rotating the crystal orientation poles to coincide, a function of determining the crystal orientation pole (l, m, n) of the specific crystal orientation pole based on the result of the rotation operation, the field ion microscope image, A program for realizing the function of displaying the determined crystal orientation pole (l, m, n) in an overlapping manner.

  According to the present invention, the person who measures the crystal orientation moves the corresponding crystal orientation pole displayed on the screen simultaneously with the FIM image by the input device, and the actual crystal orientation pole on the FIM image and the calculated crystal. The crystal orientation of the sample can be easily measured simply by matching the orientation pole.

  In addition, the angle formed by the grain boundary can be easily determined by determining the crystal orientation in the above-described procedure at two locations across the target grain boundary in the same sample.

  Furthermore, in order to obtain a Kikuchi pattern, a good crystallinity and a single crystal region of several tens of nm or more penetrating the sample are necessary, whereas the FIM image corresponds to the position of the atom on the outermost surface of the sample. If there is a single crystal portion with a radius of about 5 nm at the tip of the sample, measurement is possible.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

  The FIM image applies a high voltage to a needle-like sample having a tip diameter of about 10 nm, and a gas such as He introduced into the vacuum is ionized at the tip, and at the same time, accelerated by an electric field, and is almost linearly formed on a fluorescent screen. This is a method of observing the emission of light after reaching. Ionization tends to occur at a high electric field portion on the sample surface. Further, the sample surface is not smooth on an atomic level, and a step due to an atomic layer occurs based on the crystal lattice. Since the atoms in this step portion are relatively projected compared to neighboring atoms, the electric field is higher on the atoms than on the surroundings. As a result, atoms on the step are observed as bright spots on the observation screen. The pattern of this step is specific to the crystal structure of the sample, and there are large intervals around the poles with a small index, and the mirror index of the pole can be easily known from the pattern such as the symmetry of the surroundings.

  On the other hand, there is a one-to-one correspondence between the position on the screen and the position on the sample surface, and since the relationship can be determined geometrically, the position of the pole on the sample surface can be calculated from the position of the pole on the screen. As a result, the crystal orientation of the sample surface portion can be determined.

  In addition, the FIM image is information on the atomic arrangement on the outermost surface of the sample, and multiple low-index poles can be observed even in the 1/3 region on the hemisphere with a diameter of 10 nm, so that the Kikuchi pattern cannot be observed. Even for a sample with a fine grain structure, the crystal orientation can be determined from the pole information of the FIM image.

  The inventors have paid attention to this point, and have invented the following apparatus in order to enable anyone to measure quickly and reduce the measurement error of crystal orientation.

  Hereinafter, the crystal orientation determination device according to the present embodiment will be described in detail with reference to FIG. FIG. 1 is an explanatory diagram for explaining an apparatus configuration example of a crystal orientation determining apparatus according to the present embodiment.

  The crystal orientation determination device according to the present embodiment includes, for example, an image display device that simultaneously displays an FIM image and a calculated pole point, an input device for controlling parameters of the pole position and an input necessary for program operation, And a CPU that executes processing necessary to execute the program, a storage device that stores the program and data, and a computer that has a function of capturing an external image output directly or in the form of digital data.

  The crystal orientation determining apparatus according to the present embodiment calculates the position of the pole on the screen corresponding to the crystal orientation controlled by the input device and displays it together with the FIM image, and calculates the pole on the FIM image by the input device. And a function of determining a crystal orientation by reducing a difference in position from the upper pole. Furthermore, this orientation is stored in the apparatus, the orientation of different crystal grains in the same sample is determined by the same method, and the rotation axis and the rotation angle between the two crystal grain orientations are determined by comparing with the former. It has a function (see FIG. 1).

  Next, the relationship between the crystal orientation and the projection on the screen will be described in detail with reference to FIG. FIG. 2 is an explanatory diagram for explaining the relationship between the crystal orientation and the projection onto the screen.

  As shown in FIG. 2, the crystal axis of the reference orientation indicated by the broken arrow rotates to become the crystal axis indicated by the solid arrow. Based on this crystal axis, an arbitrary pole point can be determined on the virtual spherical surface (corresponding to the tip of the sample). This extreme point is projected onto the screen using the point Q as a light source.

  The positions of the poles on the screen are the three degrees of freedom (φ, θ, ψ) of crystal rotation, the magnification δ on the output screen, and the position ε of the center point when the ion trajectory is represented by a straight line (FIG. 2). (Refer to 5). Since the position information of one pole has two degrees of freedom, the position information of at least three poles is required to determine the five parameters, but the parameter ε is almost constant regardless of the sample and the device. Since it has been found that there is not, there are four substantial degrees of freedom, and if there is positional information of two pole points, the crystal orientation can be determined. However, in order to determine the crystal orientation more accurately, it is desirable to determine the parameters so that the positions of three or more poles coincide.

  Next, each parameter will be described in detail. The specific way of expressing the parameter is arbitrary, and the following parameter notation does not limit the present invention. In the following description, a cubic system is described for the sake of simplicity, but the same applies to other crystal systems.

As shown in FIG. 2, a virtual sphere S having a radius that coincides with the radius of curvature of the sample tip is considered, and a pole P _{l, m, n} corresponding to the Miller index (l, m, n) indicating the sample crystal orientation is defined as S. Take on. The orientation of crystal coordinates is represented by rotation from the reference coordinates. For example, using the coordinate system X fixed to the FIM apparatus, the position coordinate vector on the virtual sphere of the crystal orientation pole (l, m, n) of the crystal in the reference orientation is expressed as P _{l, m, n.} Then, the position coordinate vector P ′ _{l, m, n} on the phantom sphere of the corresponding crystal orientation pole (l, m, n) of the real sample is expressed using the rotation matrix ρ,
P ′ _{l, m, n} = ρ × P _{l. m. n}
It can be expressed as. The rotation matrix ρ can be expressed by an Euler angle that is an appropriate combination of a rotation φ around the X axis, a rotation θ around the Y axis, and a rotation φ around the Z axis. For example, among the combinations, a rotation matrix ρ represented by Euler angles of a type that is frequently used in the order of φ ° around the X axis, θ ° around the Y axis, and ψ ° around the Z axis is φ, θ , Ψ, it becomes as follows.

  FIG. 3 is an explanatory diagram for explaining parameters of distortion and magnification. Since the image on the image display device is different from the magnification of the image on the fluorescent screen, the inventors determined the magnification δ based on the image projected on the virtual screen in contact with the virtual spherical surface of the sample tip. It was displayed on the image display device. The parameter ε relating to the image distortion is a parameter obtained by normalizing the distance between the intersection point Q of the extension line of the ion trajectory and the center O of the virtual sphere having the radius R by R.

  As shown in FIG. 3, ions leaving the sample surface linearly reach the screen. The extension line of the locus intersects with one point, and it is empirically known that the intersection point Q, that is, the light source Q that projects the spherical surface onto the screen, is not the center of the virtual spherical surface S but is behind. If the light source position Q is determined, the point P on the virtual spherical surface and the point P ″ on the virtual screen are connected by the following relationship.

  The light source position can be defined by a parameter δ (= QO / R) or the like.

  The point P ′ on the screen (output screen) can be determined by the magnification parameter ε (= P′O ′ / P ″ O ″) for the point P ″ on the virtual screen.

Using the above relational expression and the rotation matrix, the theoretical position on the screen of any pole P1 _{, m, n} can be calculated and displayed simultaneously with the FIM image.

  The three parameters of the rotation matrix ρ and two parameters related to the light source position and magnification are adjusted by the input device, and the pole on the FIM image obtained from the FIM device and the theoretical position of the pole are displayed on the screen. , The rotation matrix can be determined and the crystal orientation can be determined. In this case, the degree of freedom of the position of one pole on the screen is 2, whereas there are five parameters to be determined. Therefore, in order to determine all the parameters, it is necessary to match at least three extreme positions simultaneously. There is. In order to determine the parameters more accurately, it is desirable to match more than three extreme points with the theoretical extreme positions.

  FIG. 4 is an explanatory diagram for explaining an image display example of the image display apparatus according to the present embodiment. For example, as shown in FIG. 4, the FIM image and the pole are simultaneously displayed on the right side in the figure, and the Euler angle and magnification of the crystal rotation of the FIM image currently being analyzed and the (0, 0, 1) pole on the upper left. XY coordinate positions are displayed. The Euler angle of the rotation of the crystal grain to be referred to is displayed in the left center, and the rotation angle and the orientation of the rotation axis between them are displayed below it. The lower left is a Direction Control Box including a slide bar used for parameter adjustment.

  The parameters can be entered directly by numerical values. However, it is finer to change the parameters continuously with the mouse or scroll bar on the screen as shown in FIG. It is desirable from the viewpoint of easy adjustment and input speed.

The grain boundary angle θ is determined by the rotation matrix ρ ₁ , ρ ₂ corresponding to the crystal orientation of two crystal grains sandwiching the grain boundary by the above method, and then the rotation between ρ ₁ , ρ ₂ from the property of the rotation matrix. If the diagonal sum of the matrix ρ = (ρ ₁ ) ⁻¹ · ρ ₂ is λ,
θ = cos ⁻¹ {(λ−1) / 2}
Can be obtained. However, since there is an equivalent crystal orientation pole due to the symmetry of the crystal, the smallest angle among the rotation angles between all equivalent rotation matrices is the grain boundary angle to be obtained.

  With such an apparatus, it is possible to match the poles while confirming on the screen in 1 to 2 minutes, and the crystal angle can be determined within 5 minutes after displaying the FIM image. Further, in order to discriminate the extreme points of the FIM image, if there is a reference diagram in which the extreme points are filled in with the FIM image equivalent to the crystal to be measured, it can be easily discriminated without special knowledge.

  To efficiently determine the best orientation that matches or minimizes the difference between the FIM image and the pole, the parameters that determine the position of the pole on the screen can be continuously adjusted, and the result immediately Must be displayed at the same time. For example, as shown in the Direction Control Box of the screen image on the crystal orientation determination device in FIG. 4, by adjusting a slide bar that continuously changes the parameter size with a mouse or a keyboard, Adjust the parameters. In FIG. 4, parameter X for moving the pole (0, 0, 1) horizontally on the screen and parameter Y for moving vertically are used in place of the parameters φ and θ for easy parameter adjustment.

  The three parameters for determining crystal orientation, the light source position parameter, and the magnification parameter on the screen are arbitrary. However, because of the ease of determining the orientation, as shown in the embodiment of FIG. It is desirable to adjust the rotation angle of the Euler so that the (001) pole with good visibility moves in two directions, horizontal and vertical, on the screen. For the same reason, it is desirable to simultaneously adjust the Euler angle so that the (001) pole does not move even if the position of the light source and the magnification parameter are changed.

  As described above, according to the present invention, the person who measures the crystal orientation selects three or more crystal orientation poles that are easy to recognize the pattern from the FIM image displayed on the screen, and is displayed on the screen simultaneously with the FIM image. The crystal orientation of the sample can be measured simply by moving the corresponding crystal orientation poles by the input device so that two or more actual crystal orientation poles on the FIM image are coincident with the calculated crystal orientation poles.

  Furthermore, the angle formed by the grain boundary can be easily determined by determining the crystal orientation by the above-described procedure at two locations in the same sample across the grain boundary of interest.

  In addition, by extracting two or more crystal orientation poles from the FIM image by image recognition and optimizing parameters so as to match the corresponding crystal orientation poles, the measurement time is further reduced, and even an inexperienced measurer The crystal orientation and grain boundary angle can be automatically determined.

  This eliminates the need for advanced analysis techniques such as conventional TEM observation and Kikuchi pattern analysis and analysis time required for one day.

  On the other hand, in order to obtain the Kikuchi pattern, a good crystallinity and a single crystal region of several tens of nm or more penetrating the sample are necessary, whereas the FIM image corresponds to the position of the atom on the outermost surface of the sample. If there is a single crystal portion with a radius of about 5 nm at the tip of the sample, measurement can be performed.

  In addition, according to the present invention, the image data capturing function for capturing the image data of the field ion microscope image for the crystal grains in the measurement sample into the computer, and the specific crystal orientation pole in the captured field ion microscope image, A function of rotating to match the theoretical crystal orientation pole of the target crystal grain, a function of determining the crystal orientation pole (l, m, n) of the specific crystal orientation pole based on the result of the rotation, There is provided a program for realizing a function of displaying a field ion microscope image and the determined crystal orientation pole (l, m, n) in an overlapping manner.

  Such a program is stored in a storage unit included in a computer connected to the FIM, and is read and executed by a CPU included in the computer, thereby causing the computer to function as the crystal orientation determination device. A computer-readable recording medium in which a computer program is recorded can also be provided. The recording medium is, for example, a magnetic disk, an optical disk, a magneto-optical disk, a flash memory, or the like.

  For example, when the above program is executed, a CPU included in the computer acquires image data from the FIM via an interface to which the FIM is connected, and the acquired image data is stored in a storage unit, ROM, RAM, or the like included in the computer. While storing, detection of a specific crystal orientation pole in the FIM image and calculation of a theoretical crystal orientation pole are performed. The function of rotating the target crystal grains so that the theoretical crystal orientation poles coincide with each other, the function of determining the crystal orientation poles (l, m, n), and the function of determining the crystal rotation angle between the crystal grains CPU, ROM, RAM, hard disk, and the like, and an input device and an image display device connected to the computer perform predetermined processing.

Example 1
Using a keyboard and mouse as input devices and a personal computer with a display as output device, input three parameters (Euler angle), magnification and distortion parameters to determine crystal rotation with the slide bar on the output screen. It was programmed to display poles among poles in a specific direction determined by parameters together with the FIM image.

  FIG. 5 shows a schematic cross-sectional view of the sample used in Example 1 and Example 2 shown below. FIG. 5 is an explanatory diagram for explaining a schematic cross-sectional view of a sample used in Example 1 and Example 2 shown below.

  FIG. 5- (1) is a schematic cross-sectional view of a sample including a grain boundary. Points A and B in the figure are crystal orientation measurement points by TEM Kikuchi pattern analysis, and a broken line is a schematic cross-sectional view of a sample at the time of measurement after passing through a grain boundary in Example 1. FIG. 5- (2) is a schematic cross-sectional view of a sample including a grain boundary at the tip. Points A 'and B' in the figure are crystal orientation measurement points by TEM Kikuchi pattern analysis.

  A sample 1 of bcc-Fe having one grain boundary as shown in FIG. 5- (1) is prepared, and a single crystal part (points A and B in FIG. 5- (1)) on both sides of the grain boundary is prepared by TEM. By obtaining Kikuchi patterns and analyzing them, the angle θ of crystal rotation between both single crystals was determined. The time required for TEM observation and Kikuchi pattern analysis was about 10 hours for each of 1 and 2.

  Next, FIM image II obtained by subjecting sample 1 to field evaporation using a 3D-AP apparatus and exposing crystal grain A before the grain boundary indicated by the broken line in FIG. Later, the tip of the sample was further subjected to electric field evaporation, and different crystal grains B as shown by the dotted line were exposed to obtain FIM image I. The obtained FIM image II is displayed on the display, and the calculational extreme points (0, 0, 1), (-1, 0, 1), (1, 0, 1) of the single crystal part are input by mouse and keyboard input. Was adjusted to match the poles of the FIM image, and the rotation of the crystal orientation was determined. These rotation angles were recorded for comparison (see FIG. 6), and the same operation was performed on the FIM image I to determine the rotation of the crystal orientation. By comparing the rotation angles of the FIM images I and II, the rotation angle between the two crystals was automatically calculated.

  FIG. 6 is an explanatory diagram for explaining an image display example of the image display device according to the present embodiment, and the FIM image and the pole figure analyzed in Example 2 are displayed on the right side of the drawing. The broken line indicates the grain boundary. Also, the left side in the figure is the analysis result.

  The results compared with the results of Kikuchi pattern analysis are summarized in Table 1. Compared with the angle obtained from the Kikuchi pattern analysis of the rotation angle of the grain boundary, it was within ± 2 ° C. In addition, the work time for displaying the FIM image and determining the rotation angle is within 5 minutes for one image, and the total work time for determining the rotation angle of the grain boundary is within 10 minutes. there were.

(Example 2)
The rotation angle θ between the two single crystals was determined by analyzing the Kikuchi pattern of another bcc-Fe sample 2 containing grain boundaries in the same manner as in Example 1. Next, atoms were field evaporated until a grain boundary appeared on the measurement surface with a 3D-AP apparatus, and then an FIM image was obtained. As shown in FIG. 6, using this FIM image, for two crystal grains sandwiching the grain boundary, the crystal orientation is determined in the same manner as in Example 1, and the rotation angle of the grain boundary is automatically calculated from the two rotations. It was. As shown in Table 1, the difference in the measured value of the grain boundary angle from the Kikuchi pattern analysis was 0.9 °. Further, the working time for displaying the FIM image and obtaining the rotation angle was about 8 minutes.

  This sample was again observed with a TEM and subjected to Kikuchi pattern analysis. As shown in FIG. 5- (2), the sample had a grain boundary at the tip, and the average diameter of the smaller crystal grain was about 3 nm. A Kikuchi pattern of the B ′ portion was obtained, but a Kikuchi pattern that was clear enough to be analyzed was not obtained in the A ′ portion, which is a smaller crystal grain.

  Thus, in the present invention, orientation analysis of small crystal grains that cannot be determined by a conventional method such as the Kikuchi pattern is possible.

(Example 3)
In order to show the reproducibility and the ease of work, it was investigated whether the operator A who had no experience of viewing the FIM images could determine the crystal orientation of the four FIM images obtained in Examples 1 and 2. The inventors taught worker A how to see the poles and how to operate the apparatus of the present invention in about 15 minutes, using a single FIM image as an example. Thereafter, the operator A performed the crystal orientation determination work on the remaining three FIM images using the apparatus of the present invention. As a result, the difference from the crystal rotation angle obtained in Example 1 was 1.5 ° at the maximum. Met. The analysis time for one FIM image was a maximum of 9 minutes. Thus, even a non-experienced person can easily determine the crystal orientation.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this example. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

It is explanatory drawing for demonstrating the apparatus structure of the crystal orientation determination apparatus which concerns on one Embodiment of this invention. It is explanatory drawing for demonstrating the relationship between a crystal orientation and the projection figure on a screen. It is explanatory drawing for demonstrating the parameter of distortion and a magnification. It is explanatory drawing for demonstrating the image display example of the image display apparatus which concerns on this embodiment. It is a cross-sectional schematic diagram of each sample used in the examples. It is explanatory drawing for demonstrating the image display example of the image display apparatus which concerns on this embodiment.

Claims (5)

Image data capturing means for capturing image data of a field ion microscope image of the crystal grains in the measurement sample;
Means for rotating the specific crystal orientation pole in the captured field ion microscope image so as to match the theoretical crystal orientation pole of the target crystal grain;
Means for determining a crystal orientation pole (l, m, n) of the specific crystal orientation pole based on a result of the rotation operation;
Means for superimposing and displaying the field ion microscope image and the determined crystal orientation pole (l, m, n);
A crystal orientation determination device characterized by comprising:   The crystal orientation determining device according to claim 1, wherein at least three crystal orientation poles (l, m, n) are displayed. Image data capturing means for capturing image data of field ion microscope images before and after field evaporation of the measurement sample,
For each of the field ion microscope images taken in, means for rotating each to match the theoretical crystal orientation pole of the target crystal grain with respect to the specific crystal orientation pole in the field ion microscope image,
Means for determining a crystal orientation pole (l, m, n) of each of the specific crystal orientation poles based on a result of the rotation operation;
Means for determining a crystal rotation angle between crystal grains from the crystal orientation poles (l, m, n) before and after field evaporation;
A crystal orientation determination device characterized by comprising: Image data capturing means for capturing image data of a field ion microscope image of the measurement sample surface including the grain boundary;
Means for discriminating grain boundaries in the captured field ion microscope image;
With respect to the field ion microscope image of each crystal grain distinguished at the grain boundary, means for rotating each so that the theoretical crystal orientation pole of the target crystal grain coincides with the specific crystal orientation pole in the field ion microscope image,
Means for determining a crystal orientation pole (l, m, n) of each of the specific crystal orientation poles based on a result of the rotation operation;
Means for determining a crystal rotation angle between crystal grains sandwiching a grain boundary based on each crystal orientation pole (l, m, n);
A crystal orientation determination device characterized by comprising: On the computer,
Image data capture function for capturing image data of field ion microscope images of crystal grains in the measurement sample,
A function to rotate the specific crystal orientation pole in the captured field ion microscope image to match the theoretical crystal orientation pole of the target crystal grain,
A function of determining a crystal orientation pole (l, m, n) of the specific crystal orientation pole based on the result of the rotation operation;
A function of displaying the field ion microscope image and the determined crystal orientation pole (l, m, n) in an overlapping manner;
A program to realize