JP4978922B2 - Direction measuring method for anisotropic spherical material, direction measuring device for anisotropic spherical material, and method for manufacturing spherical surface acoustic wave element - Google Patents

Description

The present invention relates to a method for measuring the direction of an anisotropic spherical material, which is mainly used for processing in which the orientation of the spherical surface acoustic wave element is controlled, an apparatus for measuring the direction of the anisotropic spherical material, and a method for manufacturing the spherical surface acoustic wave element. .

  A surface acoustic wave in which a pair of interdigital electrodes are provided on a piezoelectric body, a surface acoustic wave is generated by supplying a high frequency voltage to one interdigital electrode, and the other interdigital electrode receives the surface acoustic wave. The elements are well known in the art and are used for delay lines, oscillation elements and resonance elements, filters for selecting frequencies, chemical sensors, biosensors, remote tags, and the like.

  In such a surface acoustic wave device, there is a spherical surface acoustic wave device that can reduce propagation loss when surface acoustic waves propagate between interdigital electrodes as much as possible and dramatically improve propagation characteristic measurement accuracy ( For example, see Patent Document 1 or 2.) This spherical surface acoustic wave element is applied to a high-performance hydrogen gas sensor or the like (see, for example, Non-Patent Document 1).

  Among these spherical surface acoustic wave elements, when a spherical material such as an anisotropic piezoelectric crystal sphere is used as a base material, the crystal orientation is in the direction showing anisotropy, so which crystal axis is on the surface of the spherical material. However, depending on where the interdigital electrode is provided, there is a large difference in the propagation speed and amplitude of the surface acoustic wave at the reception location, and a large difference in the number of possible turns. For this reason, it is desirable to form the interdigital electrode at a specific suitable crystal orientation position.

  In addition, in a sensor using a spherical surface acoustic wave element, high sensitivity can be achieved by using multiple rounds, but the crystal orientation of the base on which the sensitive film is formed may affect the characteristics of the sensitive film. It is desirable to form a sensitive film at a specific suitable crystal orientation position. Furthermore, in a spherical surface acoustic wave device that branches surface acoustic waves, a diffraction pattern for branching is used. However, since the crystal orientation of the base of the diffraction pattern affects the diffraction efficiency and direction, a specific preferred crystal orientation It is desirable to form a diffraction pattern at the position.

  As a method for measuring the crystal orientation, there are an X-ray Laue method and a method using the turning property of the polarization plane of light. However, in the X-ray Laue method, when a light source material such as quartz is used as the spherical material, the diffraction from the spherical material is weak with the intensity of the X-ray that can be generated by a normal apparatus, and the detection is 10 minutes or more. Time is required, and there is a problem that it is difficult to use in the process of manufacturing the spherical surface acoustic wave device. In addition, the method using the rotational property of the polarization plane of light is simple and high speed. However, when crystal or the like is used as the spherical material, only the Z axis of the crystal can be determined, and the X axis of the crystal or There was a problem that the Y axis could not be measured and the positive and negative directions of the Z axis could not be determined. Therefore, in order to solve these problems, a method of marking the orientation with a laser at the stage of a flat substrate before processing into a sphere has been proposed (see Patent Document 3).

Japanese Patent Laid-Open No. 2001-272381 US Pat. No. 6,656,787 Kazuji Yamanaka, et al. (Kazushi YAMANAKA, et. Al.), “Ball SAW Device for Hydrogen Gas Sensor”, IE Ultrasonic Symposium (IEEE ultrasonic symposium), (USA), 2003, p. 299 Japanese Patent Application Laid-Open No. 2005-150496

  However, in the method described in Patent Document 3, it is difficult to find a mark easily after processing into a sphere. There was a problem that it could not be formed. For this reason, there has been a problem that it is difficult to produce a spherical surface acoustic wave device by measuring the crystal orientation of each spherical material such as a crystal sphere.

The present invention has been made paying attention to such problems, and can determine the direction of anisotropy with high accuracy, and can form a thin film structure at a specific suitable position to form a highly accurate spherical elastic surface. An object of the present invention is to provide an anisotropic spherical material direction measuring method, an anisotropic spherical material direction measuring device and a spherical surface acoustic wave element manufacturing method capable of producing a wave element.

In order to achieve the above object, the method for measuring the direction of an anisotropic spherical material according to the present invention provides an elastic property that propagates along a great circle of the spherical material to a predetermined position on the surface of the anisotropic spherical material. An elastic wave generating step for generating a surface wave; a measuring step for measuring a predetermined physical quantity of the surface acoustic wave that circulates along the great circle at the predetermined position; and a center of the spherical material with respect to the spherical material about an axis perpendicular to the plane containing the street the great circle, said surface acoustic said predetermined position rotated relative movement on said great circle, in a direction along the great circle for each plurality of different rotation angles from each other A step of repeating the elastic wave generating step for generating and propagating the wave and the measuring step, and a determination for determining a direction indicating anisotropy based on the physical quantity measured at each rotation angle of the repeating step Process And wherein the Rukoto.

  In the anisotropic spherical material direction measuring method according to the present invention, due to the anisotropy of the spherical material, the physical quantity measured for each rotation angle changes periodically with respect to each rotation angle. For this reason, the direction which shows anisotropy can be determined accurately based on the change of the physical quantity. A highly accurate spherical surface acoustic wave element can be produced by forming a thin film structure such as a comb-like electrode at a specific suitable position of a spherical material based on the determined direction showing anisotropy.

  The predetermined physical quantity of the surface acoustic wave to be measured may be any physical quantity that changes due to the anisotropy of the spherical material, and includes, for example, the amplitude, signal intensity, and frequency of the surface acoustic wave. In the determination step, the direction indicating anisotropy may be determined directly from the periodic change of the measured physical quantity with respect to each rotation angle. The periodic change of the measured physical quantity and the theoretically calculated physical quantity may be determined. The direction showing the anisotropy may be determined by comparing with the periodic change.

  In the method for measuring the direction of an anisotropic spherical material according to the present invention, in the elastic wave generation step, the surface acoustic wave is generated by bringing the spherical material close to or in contact with a piezoelectric element having an interdigital electrode, and the measurement is performed. In the step, it is preferable that the physical quantity is measured by the piezoelectric element that is brought close to or in contact with the spherical material in the elastic wave generation step. In this case, since the spherical material is made of a piezoelectric material, it is possible to generate a surface acoustic wave and measure a physical quantity with a piezoelectric element having an interdigital electrode. The closer the distance between the spherical material and the piezoelectric element, the greater the signal strength of the generated surface acoustic wave. Becomes higher. When the spherical material and the piezoelectric element are brought into contact with each other, it is preferable that the piezoelectric element is made of a durable material so as to prevent the deterioration of the piezoelectric element and improve the reproducibility of the measurement.

  In the method for measuring the direction of an anisotropic spherical material according to the present invention, the repeating step includes generating the elastic wave so that a distance or a contact state between the spherical material and the piezoelectric element is constant regardless of each rotation angle. And repeating the measurement step. In this case, the measurement accuracy can be kept constant. By monitoring the distance or contact state between the spherical material and the piezoelectric element, or measuring the change in impedance due to the electrical reflection of the piezoelectric element or the change in the physical quantity of the generated surface acoustic wave, And the contact state can be made constant.

  In the anisotropic spherical material direction measuring method according to the present invention, the spherical material is preferably made of crystal spheres having anisotropy. In this case, since the crystal orientation becomes a direction showing anisotropy, the crystal orientation can be determined with high accuracy. The spherical material is made of, for example, quartz.

  The great circle may be provided on a plane perpendicular to one direction showing the anisotropy of the spherical material. When a trigonal crystal sphere such as quartz is used, the Z-axis of the crystal sphere can be obtained in advance by a method utilizing the turning property of the polarization plane of light. For this reason, by providing the great circle on which the surface acoustic wave propagates on a plane perpendicular to the Z axis, the X axis and the Y axis of the crystal sphere can be accurately determined.

An anisotropic spherical material direction measuring apparatus according to the present invention includes a holding means, a surface acoustic wave generating means, a surface acoustic wave measuring means, a rotating means, and a display means, and the holding means has an anisotropic spherical shape. The material is provided so as to be able to hold from one direction of an axis passing through the center of the spherical material, and the surface acoustic wave generating means is perpendicular to the axis at a predetermined position on the surface of the spherical material held by the holding means. A surface acoustic wave propagating along a great circle on a flat plane is provided so as to be generated, and the surface acoustic wave measuring means is a predetermined physical quantity of the surface acoustic wave that circulates along the great circle at the predetermined position. The rotating means positions the positions of the surface acoustic wave generating means and the surface acoustic wave measuring means along the great circle around the spherical material held by the holding means. rotate relative to move in on the great circle Capable provided, the display means is provided such that it can display the physical quantity measured by the surface acoustic wave control unit, it is characterized.

  The anisotropic spherical material direction measuring apparatus according to the present invention can easily carry out the anisotropic spherical material direction measuring method according to the present invention. In the anisotropic spherical material direction measuring apparatus according to the present invention, the rotating means relatively rotates the surface acoustic wave generating means and the surface acoustic wave measuring means along the great circle around the spherical material, and a plurality of mutually different pluralities are obtained. The surface acoustic wave is generated and the physical quantity is measured for each rotation angle. At this time, due to the anisotropy of the spherical material, the physical quantity measured for each rotation angle changes periodically with respect to each rotation angle. For this reason, the direction which shows anisotropy can be determined accurately based on the change of the physical quantity. A highly accurate spherical surface acoustic wave element can be produced by forming a thin film structure such as a comb-like electrode at a specific suitable position of a spherical material based on the determined direction showing anisotropy.

  When using a trigonal crystal sphere such as quartz, the X and Y axes of the crystal sphere can be accurately obtained by holding the crystal sphere from one direction of the Z axis of the crystal sphere obtained in advance by holding means. You can make a good decision. The spherical material may be made of a piezoelectric body, and the surface acoustic wave generating means and the surface acoustic wave measuring means may be made of a piezoelectric element having a common interdigital electrode.

The predetermined physical quantity of the surface acoustic wave to be measured may be any physical quantity that changes due to the anisotropy of the spherical material, and includes, for example, the amplitude, signal intensity, and frequency of the surface acoustic wave. The direction of anisotropy may be determined directly from the periodic change of the measured physical quantity for each rotation angle, and the periodic change of the measured physical quantity and the theoretically predicted physical quantity The direction showing anisotropy may be determined by comparing the change.
In the anisotropic spherical material direction measuring apparatus according to the present invention, the holding means can hold the spherical material by vacuum suction, and the surface acoustic wave generating means and the surface acoustic wave measuring means are arranged on the surface of the spherical material. It may be configured to be elastically deformed when brought into contact.

  The method for manufacturing a spherical surface acoustic wave device according to the present invention is based on the direction indicating the anisotropy of the spherical material determined by the method for measuring the direction of the anisotropic spherical material according to the present invention. A thin film structure is provided at the surface position of the substrate. In the method for manufacturing a spherical surface acoustic wave device according to the present invention, the thin film structure is preferably composed of at least one of an interdigital electrode, a sensitive film, and a diffraction pattern.

  A method for manufacturing a spherical surface acoustic wave device according to the present invention is based on a direction indicating the anisotropy of the spherical material determined by the direction measuring method for the anisotropic spherical material according to the present invention. Since a thin film structure is provided at the surface position, a highly accurate spherical surface acoustic wave element can be produced. The thin film structure can be provided on the surface of the spherical material by, for example, a method of sequentially applying resist application by dipping or spraying, exposure, development, film formation, and lift-off.

According to the present invention, the direction showing anisotropy can be accurately determined, and a thin film structure can be formed at a specific suitable position to create a highly accurate spherical surface acoustic wave element. A method for measuring the direction of a spherical material, an apparatus for measuring the direction of an anisotropic spherical material, and a method for manufacturing a spherical surface acoustic wave element can be provided.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 6 show an anisotropic spherical material direction measuring method, an anisotropic spherical material direction measuring apparatus, and a spherical surface acoustic wave element manufacturing method according to an embodiment of the present invention.

  As shown in FIG. 1, the anisotropic spherical material direction measuring apparatus 10 includes two manipulators 11a and 11b, a surface acoustic wave control means 12, a light source 13, a light source side polarizing means 14, an output side polarizing means 15, and an image output. Means 16 and display means (not shown) are provided. The spherical material 1 is made of an anisotropic quartz crystal ball.

  As shown in FIG. 1, each manipulator 11 a, 11 b has an arm part 21 and a suction part 22 provided at the tip of the arm part 21. Each of the manipulators 11 a and 11 b can hold the spherical material 1 by gentle vacuum suction by the suction portion 22. The arm portion 21 may be bent elastically when a force perpendicular to the length direction is applied. Further, the suction portion 22 has a concave taper so that the suction force does not change even when the held spherical material 1 is displaced, and can be held flexibly by an air spring action. The suction part 22 is rotatable around a central axis along the suction direction. Each of the manipulators 11a and 11b may be a combination of strong vacuum suction and the arm portion 21 that is more easily displaced elastically, instead of gentle vacuum suction. Each manipulator 11a, 11b may have an elastic holding mechanism using a mechanical spring instead of a concave taper so as to hold the spherical material 1 flexibly and elastically.

  One manipulator 11a is arranged so as to be able to hold the spherical material 1 from above a vertical axis passing through the center of the spherical material 1 (Z-axis in FIG. 1), and can advance and retreat along the vertical axis. One manipulator 11a can rotate the held spherical material 1 around a vertical axis. The other manipulator 11b is arranged so as to hold the spherical material 1 from one direction of the horizontal first horizontal axis (X axis in FIG. 1) passing through the center of the spherical material 1 held by the one manipulator 11a. It is possible to advance and retreat along the first horizontal axis. The other manipulator 11b can rotate the held spherical material 1 around the first horizontal axis. The other manipulator 11b constitutes holding means and rotating means.

  As shown in FIG. 1, the surface acoustic wave control means 12 has a support stage 23 and a piezoelectric element 24, and constitutes a surface acoustic wave generation means and a surface acoustic wave measurement means. The support stage 23 is disposed below the one manipulator 11a, moves along the vertical axis, and can adjust the distance from the spherical material 1 held by the one manipulator 11a. Further, the support stage 23 is rotatable coaxially with the suction part 22 of one manipulator 11a. The piezoelectric element 24 has a pair of interdigital electrodes 25 formed on a substrate, and is fixed to the center of rotation on the upper surface of the support stage 23. The piezoelectric element 24 can apply a high frequency voltage to the interdigital electrode 25.

  The surface acoustic wave control means 12 moves the support stage 23 upward, and brings the interdigital electrode 25 of the piezoelectric element 24 closer to or in contact with the spherical material 1 held by the other manipulator 11b. A surface acoustic wave propagating along a great circle on a plane perpendicular to the first horizontal axis can be generated on the surface. Further, the surface acoustic wave control means 12 can measure a predetermined physical quantity of the surface acoustic wave that has circulated along a great circle by the interdigital electrode 25 of the piezoelectric element 24 that approaches or contacts the spherical material 1. As a result, the other manipulator 11b rotates the suction portion 22 to elastically move the spherical material 1 held by the suction portion 22 along a great circle on a plane perpendicular to the first horizontal axis. The surface wave control means 12 is configured to be relatively rotatable.

  As shown in FIG. 1, the light source 13 is formed from a spherical material 1 held by each manipulator 11a, 11b on a second horizontal axis (Y axis in FIG. 1) perpendicular to the vertical axis and the first horizontal axis. It is arranged with an interval of. The light source side polarization unit 14 includes a polarizing plate and a diffusion plate, and is disposed between the light source 13 and the spherical material 1 held by the manipulators 11a and 11b. The output side polarizing means 15 is composed of a polarizing plate, and is disposed on the opposite side of the light source side polarizing means 14 with respect to the spherical material 1 held by the manipulators 11a and 11b. The image output means 16 has a CCD camera 26 and a monitor screen (not shown) connected thereto, and is opposite to the spherical material 1 held by the manipulators 11a and 11b with respect to the output side polarization means 15. Is arranged. The image output means 16 captures the spherical material 1 held by the manipulators 11a and 11b with the CCD camera 26 and outputs it to the monitor screen.

  The display means comprises a computer and is connected to the piezoelectric element 24 of the surface acoustic wave control means 12. The display means can acquire a predetermined physical quantity of the surface acoustic wave measured by the piezoelectric element 24 and display it on the display screen. The display means can store and analyze the acquired predetermined physical quantity in the memory, print it on a printer, and the like.

  In a specific example, the spherical material 1 has a diameter of 10 mm. Each of the manipulators 11a and 11b can control movement along the vertical axis or the first horizontal axis in units of 1 μm and rotation of the suction unit 22 in units of 1/250 °.

The anisotropic spherical material direction measuring method according to the embodiment of the present invention is performed by the anisotropic spherical material direction measuring apparatus 10 as follows.
First, the Z-axis of the spherical material 1 made of crystal spheres is determined by a known method using concentric marks based on the turning property of the polarization plane of light. That is, the spherical material 1 is held by one of the suction portions 22 of each of the manipulators 11a and 11b, the light from the light source 13 is applied to the spherical material 1 through the light source side polarization means 14, and the light that has passed through the spherical material 1 Is observed by the image output means 16 via the output side polarization means 15. At this time, interference fringes are observed on the monitor screen of the image output means 16. Since the center position of the interference fringe corresponds to the Z axis, the center of the interference fringe is positioned at the center of the monitor screen while rotating the suction portion 22 and delivering the spherical material 1 between the manipulators 11a and 11b. Thereby, the Z-axis of the spherical material 1 coincides with the second horizontal axis, and the Z-axis can be determined.

  As shown in FIG. 2A, the spherical material 1 in which the Z axis coincides with the second horizontal axis is held by one manipulator 11a. Next, as shown in FIG. 2 (b), the suction part 22 of one manipulator 11a is rotated 90 degrees, the other manipulator 11b is moved closer, and the other manipulator 11b causes the spherical material 1 to be pointed on the Z axis. Hold on. Next, as shown in FIG. 2C, one manipulator 11a is separated from the spherical material 1 and moved upward to be retracted.

  As shown in FIG. 2 (d), the support stage 23 is raised to bring the pair of interdigital electrodes 25 of the piezoelectric element 24 into contact with the surface of the spherical material 1. As a result, a surface acoustic wave that circulates along the great circle of the spherical material 1 can be generated, and the signal intensity and frequency of the surface acoustic wave that circulates along the great circle can be measured. At this time, as shown in FIG. 3, since the displacement proportional to the contact force is generated by the elastic deformation of the arm portion 21 of the other manipulator 11b, the displacement is measured by an optical system such as the image output means 16. The contact force can be kept constant and the generation and measurement of surface acoustic waves can be controlled and optimized. For this reason, measurement accuracy can be kept constant. At the same time, since damage due to contact between the spherical material 1 and the interdigital electrode 25 due to excessive stress can be prevented, the manufacture of a highly accurate spherical surface acoustic wave element can be maintained. Further, since the suction portion 22 is tapered on the concave surface, when the interdigital electrode 25 comes into contact, an air spring action that displaces the sphere in a direction that reduces the contact force can be exerted.

  Next, as shown in FIG. 2E, the support stage 23 is moved and fixed so that the spherical material 1 and the interdigital electrode 25 are opposed to each other in a non-contact state with a certain gap. Further, while rotating the other manipulator 11b, the spherical material 1 is rotated around the first horizontal axis, and generation and measurement of surface acoustic waves are repeated for each of a plurality of different rotation angles. At this time, the spherical material 1 and the interdigital electrode 25 are brought into contact with each other, thereby eliminating the friction between the spherical material 1 and the interdigital electrode 25 and smoothly sliding, thereby preventing the interdigital electrode 25 from being damaged. At the same time, precise attitude control is possible.

  Here, as shown in FIGS. 4A and 4B, the relationship between each crystal axis on the flat plate and anisotropy is known for the quartz crystal based on the theoretical analysis result. That is, as shown in FIG. 4B, it is known that the velocity of the surface acoustic wave to be measured increases and decreases with a period of 60 degrees as a function of the rotation angle γ. At this time, the minimum speed is the −Y axis orientation of the crystal, and the direction perpendicular to this is the X axis orientation. The analysis of surface acoustic waves on crystal spheres is not easy because the propagation direction with respect to the crystal axis changes every moment according to the propagation. However, as shown in FIG. 4 (c), by considering local propagation and assuming that the azimuth is constant, the same treatment as on a flat plate is possible.

  As shown in FIG. 5, the relative speed change due to metallization of the surface proportional to the signal intensity, measured at each rotation angle of the other manipulator 11b, periodically changes with respect to the rotation angle. By comparing the periodic change of the measured signal strength shown in FIG. 5 with the theoretically calculated periodic change, the direction indicating anisotropy can be determined with high accuracy. That is, by measuring the azimuth angle γ at which the signal intensity of the surface acoustic wave shown in FIG. 5 is minimized, the −Y axis azimuth can be determined. Further, the X-axis direction can be determined as a direction orthogonal to the −Y axis by 90 degrees.

  Moreover, as shown in FIG. 6, in order to perform transmission / reception on the conditions with a fixed wavelength, the frequency measured for each rotation angle of the other manipulator 11b changes periodically with respect to a rotation angle. By comparing the periodic change in the measured frequency shown in FIG. 6 with the theoretically calculated periodic change shown in FIG. 4B, the direction indicating anisotropy is accurately determined. be able to. That is, by measuring the azimuth angle γ at which the frequency of the surface acoustic wave shown in FIG. 6 is minimum, the −Y axis azimuth can be determined. Further, the X-axis direction can be determined as a direction orthogonal to the −Y axis by 90 degrees.

  A highly accurate spherical elastic surface is formed by forming a thin film structure such as an interdigital electrode, a sensitive film or a diffraction pattern at a specific suitable position of the spherical material 1 based on the crystal orientation showing the anisotropy thus determined. Wave elements can be created.

As described above, according to the anisotropic spherical material direction measuring method, the anisotropic spherical material direction measuring device 10 and the spherical surface acoustic wave device manufacturing method according to the embodiment of the present invention, according to the exact crystal orientation. Thus, it is possible to optimize a spherical surface acoustic wave device using a crystal sphere whose transmission / reception sensitivity changes. For example, the circular characteristics of the spherical surface acoustic wave element, the diffraction efficiency of the branched spherical surface acoustic wave element, and the sensor sensitivity of the spherical surface acoustic wave element can be optimized. In addition, when the crystal orientation of the base on which the sensitive film is formed affects the characteristics of the sensitive film, it is expected to improve the sensitivity and response speed by controlling the orientation of the sensitive film. As a result, it is expected to dramatically improve the performance of delay lines, oscillation elements and resonant elements, frequency selection filters, chemical sensors, biosensors, remote tags, etc., which were impossible with conventional spherical surface acoustic wave elements. be able to.

It is a perspective view which shows the direction measuring apparatus of the anisotropic spherical material of embodiment of this invention. It is the (upper stage) side view which shows the procedure of the direction measurement method of the anisotropic spherical material of embodiment of this invention, (lower stage) The top view of a surface acoustic wave control means. 1A is a side view showing a state in which the spherical material is brought close to the surface acoustic wave control means, and FIG. 1B is a view showing a state in which the spherical material is brought into contact with the surface acoustic wave control means. It is a side view which shows a state. (A) perspective view showing the relationship between each crystal axis on the quartz plate and rotation angle γ, showing the theory of sound velocity anisotropy of surface acoustic waves, (b) as a function of the rotation angle γ on the quartz plate. It is a graph which shows a speed change, (c) It is a perspective view which shows the relationship between each crystal axis on the crystal sphere of quartz, and the rotation angle (gamma). Surface by metallization of the surface representing the signal intensity as a function of the manipulator rotation angle γ as measured by the anisotropic spherical material direction measuring method and anisotropic spherical material direction measuring device of the embodiment of the present invention It is a graph which shows change ( ^DELTA ) V / V (x10 < ^-3 >) of the relative velocity of a wave. The change of the signal frequency f as a function of the rotation angle γ of the manipulator measured by the anisotropic spherical material direction measuring method and the anisotropic spherical material direction measuring apparatus according to the embodiment of the present invention is expressed as a velocity V _R ( = Λ _R f).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Spherical material 10 Direction measuring apparatus 11a, 11b Manipulator 12 Surface acoustic wave control means 13 Light source 14 Light source side polarization means 15 Output side polarization means 16 Image output means 21 Arm part 22 Suction part 23 Support stage 24 Piezoelectric Element 25 Interdigital electrode 26 CCD camera

Claims (10)

An elastic wave generating step of generating a surface acoustic wave propagating along a great circle of the spherical material at a predetermined position on the surface of the spherical material having anisotropy;
A measuring step of measuring a predetermined physical quantity of the surface acoustic wave that has circulated along the great circle at the predetermined position;
With respect to the spherical material, the predetermined position is relatively rotated on the great circle around an axis that passes through the center of the spherical material and is perpendicular to the plane including the great circle. Repeating the elastic wave generating step and the measuring step to generate and propagate the surface acoustic wave in a direction along the great circle, and
A determination step of determining a direction showing anisotropy based on the physical quantity measured for each rotation angle of the repetition step;
A method for measuring the direction of an anisotropic spherical material, comprising: 2. The method for measuring the direction of an anisotropic spherical material according to claim 1, wherein the predetermined physical quantity of the surface acoustic wave measured in the measuring step is a frequency. In the elastic wave generation step, the surface acoustic wave is generated by bringing the spherical material close to or in contact with a piezoelectric element having a comb-shaped electrode,
The measurement step measures the physical quantity by the piezoelectric element that is approached or brought into contact with the spherical material in the elastic wave generation step.
The method for measuring the direction of an anisotropic spherical material according to claim 1 or 2 . The repeating step repeats the elastic wave generating step and the measuring step so that the spacing or contact state between the spherical material and the piezoelectric element is constant regardless of each rotation angle.
The method for measuring the direction of an anisotropic spherical material according to claim 3 . 5. The method for measuring the direction of an anisotropic spherical material according to claim 1 , wherein the spherical material is made of crystal spheres having anisotropy. The anisotropic method according to claim 1, 2, 3, 4, or 5 , wherein the great circle is provided on a plane perpendicular to one direction showing anisotropy of the spherical material. Of measuring the direction of a spherical material. Holding means, surface acoustic wave generating means, surface acoustic wave measuring means, rotating means and display means,
The holding means is provided so that a spherical material having anisotropy can be held from one direction of an axis passing through the center of the spherical material,
The surface acoustic wave generating means is provided to generate a surface acoustic wave propagating along a great circle on a plane perpendicular to the axis at a predetermined position on the surface of the spherical material held by the holding means,
The surface acoustic wave measuring means is provided so as to be able to measure a predetermined physical quantity of the surface acoustic wave that has circulated along the great circle at the predetermined position,
The rotating means relatively positions the surface acoustic wave generating means and the surface acoustic wave measuring means on the great circle along the great circle around the spherical material held by the holding means. It provided rotatably moved,
The display means is provided to be able to display the physical quantity measured by the surface acoustic wave control unit.
An apparatus for measuring the direction of anisotropic spherical material. The holding means can hold the spherical material by vacuum suction, and is configured to elastically deform when the surface acoustic wave generating means and the surface acoustic wave measuring means are brought into contact with the surface of the spherical material. An apparatus for measuring the direction of an anisotropic spherical material according to claim 7 . A thin film structure is provided at a predetermined surface position of the spherical material based on the direction showing the anisotropy of the spherical material determined by the method for measuring the direction of the anisotropic spherical material according to claim 1. A method for producing a spherical surface acoustic wave device. 10. The method for manufacturing a spherical surface acoustic wave device according to claim 9 , wherein the thin film structure is composed of at least one of an interdigital electrode, a sensitive film, and a diffraction pattern.

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