JP2005150496A - Anisotropic transparent solid material, spherical surface acoustic wave element and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an anisotropic transparent solid material which can be manufactured only by one crystal axis identification of a crystal material on the basis of a mark even in a post process including surface processing such as a polishing process, by previously forming the mark indicating a crystal axis direction which does not disappear after spherical processing on a crystal sphere, by performing spherical processing after forming the mark indicating the crystal axis in the crystal material in a cut state of the material or before performing spherical processing; to provide a manufactured spherical surface acoustic element; and to provide a method capable of speedy and simply forming a mark indicating the crystal axis of the spherical surface acoustic wave element using the crystal sphere. <P>SOLUTION: The anisotropic transparent solid material is obtained by putting a mark indicating an azimuth axis in a solid material having transparency and anisotropy by using laser light. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to internal processing of a transparent solid material, and in particular, an anisotropic transparent solid material in which the direction of crystal axes is easily revealed without damaging the surface of an anisotropic material such as a crystal material. The present invention relates to a technique relating to a spherical surface acoustic wave element and a method for manufacturing the same.

  2. Description of the Related Art A surface acoustic wave element has been well known as one that generates surface acoustic waves on a substrate and receives surface acoustic waves generated on the substrate. A surface acoustic wave element is provided with a pair of comb-shaped electrodes on a piezoelectric body. By supplying a high frequency voltage to one comb-shaped electrode, a surface acoustic wave is generated in the direction in which the one comb-shaped electrode is aligned, The other comb-shaped electrode is arranged in the moving direction of the surface acoustic wave generated from the one comb-shaped electrode and receives the surface acoustic wave. The surface acoustic wave element is used for a delay line, an oscillation element and a resonance element for a transmitter, a filter for selecting a frequency, a chemical sensor, a biosensor, a remote tag, or the like.

  As one proposal for reducing the propagation loss when a surface acoustic wave propagates between a pair of comb-shaped electrodes in such a surface acoustic wave element as much as possible and increasing the accuracy of the resonance frequency, Patent Document 1 discloses. There is such a spherical surface acoustic wave device. In such a spherical surface acoustic wave device, since an anisotropic piezoelectric crystal sphere is used as a base material, an interdigital electrode (comb electrode) is provided at which position with respect to which crystal axis on the surface of the crystal sphere. Thus, a large difference occurs in the generated surface acoustic wave and its propagation speed. However, when creating a spherical acoustic wave device (element) by using a piezoelectric crystal sphere as a base material and forming interdigital electrodes on its surface, if the piezoelectric crystal material is processed into a sphere, the direction of the crystal axis depends on the shape. It becomes difficult to determine, and in order to perform patterning and device processing that are indispensable for device fabrication, the crystal orientation of each crystal sphere must be measured, especially for measuring X-rays, etc. When such a method is adopted, there is a problem that the apparatus is expensive and the production speed is not increased.

  A method called X-ray Laue method is generally considered as a method for measuring the crystal orientation of crystal spheres.

  When a single crystal material is grown, it can often be discriminated from the shape of the single crystal because of the dependence of the crystal growth rate unique to the crystal on the crystal orientation. The axis can no longer be identified.

  In the X-ray Laue method, when an X-ray beam is irradiated from a certain direction of a crystal, the X-ray is reflected in a direction according to the crystal plane according to the arrangement of atoms constituting the crystal. It measures the crystal direction from a pattern, and is often used in the material cutting process of a crystal oscillator.

As a method for measuring the crystal axis of a spherically processed crystal sphere, there is a method using the rotating physical properties of light shown in FIG. In particular, in crystal, LiNbO ₃ , LiTaO _3, etc., when the light that has been polarized and transmitted in the Z-axis direction by the method shown in FIG. A concentric mark (FIG. 2B) appears due to the swirlability and the geometric feature as a sphere. The direction in which this mark can be seen at the center of the sphere can be determined as the Z-axis direction. The disadvantage of this method is that it can be used for measurement in the Z-axis direction, but for example the X crystal axis or Y crystal axis of quartz cannot be measured. Further, since the direction of the Z-axis cannot be determined, there is a problem that it is not possible to deal with crystal spheres where the front and back are important.

  A general method of processing a crystal material into a crystal sphere will be described with reference to FIG.

  The wafer material 1 is cut out from a crystal material (not shown) for taking out many crystal spheres.

  As shown in FIG. 3A, the massive crystal material is once cut into a flat plate at a plane perpendicular to the Z direction of the crystal axis, for example. This wafer material 1 is called a Z-cut crystal substrate. This Z-cut crystal substrate is further finely cut and cut into a large number of polygonal column chips (here, cubic chips) as shown in FIG. Next, the corners are removed in a process (not shown), and finally a pointed part is gradually scraped off by rotating while applying pressure in a spherical groove called an Imahashi-type round ball polishing machine (not shown).

  Alternatively, the material is mixed with an appropriate polishing object and stirred for a long time, so that the material naturally collides with each other, or the angle is removed by friction with the abrasive to form the crystal sphere 3.

  In general, when the crystal sphere 3 is formed using such a method, the diameter of each crystal material having an initial cube or rough corner is approximately 1.4 of the diameter of the target crystal sphere 3. Double size is required, and it is made into a perfect sphere as shown in FIG.

  As shown in FIG. 4, there is a spherical surface acoustic wave element 4 as one of new surface acoustic wave devices. The spherical surface acoustic wave element 4 generates a surface acoustic wave 41 on a circular continuous surface made of a piezoelectric material and makes multiple rounds. When the surface acoustic wave 41 propagates on the annular surface, It is expected as a sensor that electrically measures the change of the circulation speed due to the adhered substance. In order for the surface acoustic wave 41 to propagate around the surface of the crystal sphere 3, it is necessary to excite the surface acoustic wave about the orientation determined by the crystal. For this purpose, the interdigital electrode 42 for exciting and detecting the surface acoustic wave 41 at a specific angle determined by the crystal orientation of the crystal sphere 3 must be formed using a method such as photolithography.

  For example, in the method of rotating the surface acoustic wave 41 through the annular path 43 called a quartz Z-axis cylinder, the spherical surface acoustic wave element 4 is out of the annular region as shown in FIG. It is known that even if the portion 44 (the vicinity corresponding to the pole when the circular path is the equator) is cut, the circular characteristics are not greatly affected. For this reason, it has been desired to use this part as a surface for cutting the surface flatly to use it as an electronic component such as another IC chip, or as a connection space for the interdigital electrode 42, or to fix it to the substrate. As a method for processing the flat surface of the pole, a method of polishing the entire resin while being hardened with a resin or the like is used. However, it is difficult to polish a fine object with high planar accuracy, resulting in a problem of high cost.

  As described above in detail, it is required to determine the crystal axis of the crystal sphere 3 with high accuracy, but a simple and low-cost method has not been found.

  In the present invention, a method for leaving a mark inside the crystal sphere 3 and determining the crystal axis visually is proposed. Since the marking indicating the crystal axis disappears by polishing even if it is applied to the surface of the wafer material 1 or the polygonal column chip 2, it is necessary to mark the inside of the crystal sphere 3. However, if the engraving is left on the ring portion, it becomes a defective product. Therefore, it is necessary to engrave only a minute portion inside the transparent body on the micrometer order without damaging the surface of the transparent body.

  In particular, in recent years, the usefulness of ultrashort pulse lasers has been reported in the internal processing of transparent materials. As shown in Non-Patent Document 1, an optical waveguide can be formed by changing the refractive index, or Patent Document 2 can be used. As shown in FIG. 5, it is possible to form microdots inside the glass.

  The marking method according to the present invention is based on the use of the basic characteristics of the ultrashort pulse laser described above.

Known literature is as follows.
JP 2002-26688 A JP-A-11-267861 Katsumi Midorikawa, “Femtosecond laser interaction with matter”, Journal of Laser Processing Vol. 8, no. 3 (2001)

  In a state where the crystal material is cut or before spherical processing, a mark indicating the crystal axis is formed inside the material and then spherical processing is performed, and a mark indicating a crystal axis direction that does not disappear even after spherical processing is performed. By forming it on the crystal sphere, it is possible to identify the crystal axis of the material only once, and it can be manufactured on the basis of the inscription in the subsequent process including surface processing such as a polishing process. Provided are a material capable of easily forming a mark indicating the crystal axis of a spherical surface acoustic wave element using a crystal sphere, and a spherical surface acoustic wave element using this material.

  In order to solve the above-mentioned problems, first, the first invention of the present invention is that a solid material having transparency and anisotropy is engraved with a laser beam to indicate an azimuth axis. An anisotropic transparent solid material is provided.

  This eliminates the need for expensive and time-consuming measurements such as the X-ray Laue method for each crystal sphere in order to perform patterning and device processing that are indispensable for the manufacture of devices as in the prior art. I can do it.

  The anisotropic transparent solid material according to claim 1, wherein the laser light is an ultrashort pulse laser having an instantaneous power of GW and a pulse width of 1 picosecond or less. Is to provide.

  This can solve the light absorption characteristic problem due to the material.

  According to a third aspect of the present invention, there is provided the anisotropic transparent solid material according to claim 1 or 2, wherein the inscription is a void.

  According to a fourth aspect of the present invention, there is provided a spherical surface acoustic wave device having an inscription inside, produced using the anisotropic transparent solid material according to any one of claims 1 to 3. .

  The fifth invention of the present invention is a method for manufacturing a spherical surface acoustic wave device made of a spherical solid material having transparency and anisotropy, and includes at least the following steps 1 to 3. It is an object of the present invention to provide a method for manufacturing a spherical surface acoustic wave element having an azimuth axis that is visible inside.

Step 1. An orientation that is visible with respect to at least one orientation inside the anisotropic transparent solid material by irradiating a laser beam to the anisotropic transparent solid material having a plane that maintains a certain angle with respect to one crystal orientation Step of marking the shaft Step 2. Step of cutting the anisotropic transparent solid material into chips Step 3. A step of processing the tip-shaped anisotropic transparent solid material into a spherical shape while leaving the azimuth axis engraved in step 1 inside

  As is clear from the above description, according to the present invention, the following effects can be obtained.

In order to visually confirm the orientation of an anisotropic transparent solid material such as a single crystal material having a surface with a known crystal orientation, the surface is damaged by irradiating an energy beam with a pulse width of nanoseconds or less from the surface. In order to carry out patterning and processing of elements that are indispensable for the manufacture of conventional elements by leaving at least a part of the inscriptions on the inside of the anisotropic transparent solid material. It is possible to eliminate expensive and time-consuming measurement such as X-ray Laue method for each crystal sphere.

  The process of making the marking inside the anisotropic transparent solid material is performed before the wafer material is cut into a plurality of polygonal column chips or before the rod-shaped material is cut into a cylinder or a polygonal column chip. The identification work can be performed only once, and it can be manufactured based on the stamp in the subsequent process. Since the anisotropic transparent solid material of the present invention has an arbitrary number of voids formed at arbitrary coordinates inside the crystal sphere, it not only indicates the existence of the crystal axis, but also its direction and a plurality of crystal axes. Can also be engraved. If processing into a spherical surface acoustic wave element is performed according to this information, for example, a quartz material has a large influence on the interdigital electrode formation position, and if the formation position is shifted, a significant difference appears in the propagation speed of the surface acoustic wave. Therefore, it becomes an anisotropic transparent solid material that can easily determine the orientation of the X axis and the Y axis.

  The energy beam that forms the gap or set of gaps to be engraved is a laser beam that has a high energy density at the gap generation position, a pulse laser (hereinafter referred to as ultrashort) with an instantaneous power of GW and a pulse width of 1 picosecond or less. (This is called a pulse laser or femtosecond laser), so there is no problem with the light absorption characteristics of the material, and extremely fine engraving can be easily performed only inside the anisotropic transparent solid material without damaging the material surface. Therefore, the azimuth axis specifying accuracy is increased.

  Further, when forming a spherical base material by forming an inscription on the surface of the anisotropic transparent solid material and manufacturing the spherical base material by processing the anisotropic transparent solid material, at least a part of the inscribed surface of the azimuth plane is left. By manufacturing crystal spheres in this way, it becomes possible to specify the crystal axis by an inexpensive and simple detection method, and the productivity is remarkably improved.

    An anisotropic transparent solid material, a spherical surface acoustic wave device and a method for manufacturing the same according to the present invention will be described with reference to the drawings.

  The inscription described in the present invention refers to recording three-dimensional coordinates on a target solid material, or the coordinates. Specifically, laser light irradiation is performed to determine any arbitrary solid material determined for the solid material. It is to form a void such that the azimuth axis can be read by making a relative comparison between the outer shape of the solid material and the void formation position by visual recognition using a device such as a microscope.

  The azimuth axis described in the present invention refers to three-dimensional spatial coordinate information in the target solid material, and not only the direction of anisotropy in the solid material but also, for example, three axes of XYZ orthogonal to each other. Also, an artificially determined axis that is not necessarily parallel to the direction of anisotropy in the solid material is included.

  Therefore, if the azimuth axis is engraved, it is possible to determine the orientation (azimuth axis) of the left and right sides, back and front, etc. of the solid material only by looking at it by marking (indicating) the visible solid material. Is to do.

The anisotropic transparent solid material of the present invention is not only a crystalline material described in detail below, but also a solid material that is transparent and difficult to identify the anisotropic axis by visual recognition, and is marked with a direction axis. All materials are included, and the shape may be any of wafer, rod, polygonal column, cylinder, and sphere. Here, the term “transparent” is sufficient if it is transparent to the energy beam used for forming the indicia that is a gap, and the degree of transparency is within the range not departing from the gist of the present invention. It is only necessary to penetrate and converge and to be processed accordingly.

  The crystal sphere 3 in the present invention is not limited to the true spherical shape shown in the spherical surface acoustic wave element of FIG. 4 (A), but can be any shape as long as the surface acoustic wave 41 circulates in the annular path 43. For example, the circular ring shape is completed such as a shape having an annular region such as a drum shape in which a part of a sphere is cut off as used in the spherical surface acoustic wave element of FIG. Including the base material at different stages.

  It should be noted that even if a part of the surface is subsequently scraped or partially flat, the crystal sphere 3 is not changed.

    A detailed processing procedure for performing sphere processing from a polygonal column material is a well-known technique and will not be described.

In addition, when sphere processing is started from a small polygonal column material in the thickness direction, the surface in one direction that was small is less likely to be scraped with contact with other materials, and the other surface is scraped to the end. It is known that even if it becomes a crystal sphere having an annular path close to the sphere surface, it remains as a plane,
By leaving the crystal axis direction of the crystal sphere as a plane that suggests the crystal axis even after forming the spherical surface, if the post-process is performed based on this plane, the crystal sphere is patterned and processed in the direction determined by the crystal axis. Can be done.

  In particular, when the crystal sphere 3 is formed from the wafer material 1 whose crystal axis direction is clarified, a crystal plate having a crystal plane which is important in the process process is cut after the crystal sphere 3 is completed. By performing the processing while leaving the crystal plane, it is possible to leave more information on the crystal axis direction in the crystal sphere without any special operation.

  In the present invention, it is necessary to first determine the axial orientation in the surface of the wafer material 1 cut out from the crystal material, and to maintain the coordinate position of the void 13 stamped based on the axial orientation after the formation of the crystal sphere. Usually, in order to form crystal spheres, the wafer material is cut and spherically processed to form crystal spheres, and then provided so that at least a plurality of cavities as inscriptions are present therein.

  At this time, if the gap 13 is formed so that the coordinates of at least two points can be specified, it is possible to reproduce all axial directions of the crystal sphere from the position of the gap 13. The method of marking that suggests the crystal axis orientation will be specifically described with reference to FIGS.

  The shape of the crystal sphere 3 forming the spherical surface acoustic wave element 4 can be roughly classified into two types as shown in FIG. In FIG. 4A, a transparent solid material is processed into a spherical shape and then manufactured by forming interdigital electrodes 42 on its surface. For example, an elastic surface is formed on an annular path 43 called a quartz Z-axis cylinder. When creating the wave 41 to propagate, the interdigital electrode 42 must be formed in the equator direction when the Z-axis direction is the ground axis. For this reason, if at least two points suggesting the Z-axis direction are imprinted on different coordinates only in the Z direction of the crystal axis before the anisotropic transparent solid material is subjected to the sphere processing, the two points after the sphere processing are also obtained. The Z-axis direction can be known from the azimuths connecting the Z and the Z-axis cylinder path can be recognized based on the Z-axis direction.

However, although the interdigital electrode 42 is formed at any position on the Z-axis cylinder path (corresponding to the equator with the Z-axis as the ground axis), it functions as the spherical surface acoustic wave element 4 for the time being. Even on the equator, the position varies depending on the position, and the position varies greatly depending on where the interdigital electrode 42 is provided and the surface acoustic wave 41 is generated. Therefore, it is necessary to record the XY directions in order to keep the element specifications constant. As is apparent geometrically, in order to record at least two crystal axes including their orientations, it is necessary that the gaps 13 indicating the coordinates of at least three points be imprinted in a non-aligned arrangement. . This is possible by grasping the relationship between the spatial arrangement (coordinates) of the three points and the XYZ crystal axes in advance. The simplest case is shown in FIG. The z-axis direction is indicated by the gaps z1 and z2, and the Y direction is indicated by the gap y1. If z1, z2, and y1 are not at least spatially in the position of an isosceles triangle, for example, all three crystal orientations of quartz can be recorded.

  The possibility of showing the Z axis of the crystal sphere 3 at one point will be described with reference to FIG. In this example, one gap z1 is formed on the outside of the sphere. The air gap and the surface of the sphere closest to the air gap are connected, and for example, this can be determined as the Z axis. Also, the direction of the Z axis can be determined based on which side the gap is located on the Z axis. Needless to say, in order to make this possible, it is necessary to increase the relative positional accuracy of the polygonal column chip shown in FIG.

  The possibility of showing all the XYZ3 axes of the crystal sphere at two points will be described with reference to FIG. In this example, one gap z1 is provided at the edge of the sphere, and the other gap y1 does not overlap z1, and is imprinted at a position closer to the center of the sphere than z1 but not the center of the sphere. The gap closest to the sphere surface is determined as z1, and the gap next to the sphere surface is determined as y1. It is possible to connect the gap z1 and the spherical surface closest to the gap z1 and determine this as the Z axis. Further, for example, it can be determined that the Z-axis is in the positive direction from the center of the crystal sphere through the gap z1 toward the sphere surface. If the plane formed by the center of the crystal sphere and the three points z1 and y1 is the YZ plane, the direction in which the gap y1 is located with respect to the center of the crystal sphere can be determined as the positive Y axis. From the intersection of the two axes to the geometrical orientation of the X axis will be understood.

  Next, FIG. 6 is an example in which the sphere has a shape showing at least one direction. In this case, the crystal orientation can be recorded with a small number of voids. For example, this is a case where a plane is present. Here, if it is known in advance that a surface having a normal line about the Z-axis is formed, two gaps as shown in FIG. Can be recorded in the Y direction or the Z direction as long as they are not parallel to the Z axis. Alternatively, as shown in FIG. 6B, even if there is only one gap, the direction can be recorded as, for example, the + Y axis by utilizing the fact that it is not located at the center of the sphere.

  In FIG. 6, the portion 44 out of the circular path existing in two places in the crystal sphere 3 shows a shape cut out by a plane having the Z axis as a normal line, but only one of them is a true spherical crystal. If the sphere is formed by cutting or the like by grinding or the like so that both are made unintentional, and the Z axis orientation is expressed by this processing, all three axes can be expressed even with only one coordinate.

  As described above, there are various methods for recording the crystal axis direction by imprinting voids in the anisotropic transparent solid material, and any of them can be easily estimated geometrically and used. In particular, in the case of marking with a laser beam, since the void shape is usually a spindle, it can be easily assumed that two coordinates are imprinted by one void depending on the shape and one crystal axis is indicated.

  Thus, the present invention is an anisotropic transparent solid material in which the crystal axis can be known from the outer shape of the crystal sphere, the geometric arrangement of the voids engraved therein, or the coordinates indicated by the shape of the voids. .

  In this example, a quartz crystal is taken as an example, and an anisotropic transparent solid material with XYZ three-axis markings has been described. However, as described above, it is transparent and voids can be formed by laser light. The present invention can be applied to any solid material to be engraved, and the angle and number of shafts are optional items that can be determined according to the purpose.

It is effective to use laser light as an energy source for forming the void. As shown in FIG. 7 and FIG. 8, the laser beam 45 can be focused at various positions and regions in the wafer material 1 by changing the beam shape. Anything may be used for the purposes of the invention and will not be described here.

  However, as shown in FIG. 8, if a laser beam having an energy distribution capable of forming a plurality of voids 13 (engraved) at once is used, a crystal orientation in a specific direction can be recorded by one irradiation of the laser beam 45. Therefore, processing with high throughput is possible and desirable.

  It has been reported that this is possible by devising a condensing optical system with an ultrashort pulse laser.

  In addition, when the axial direction is imprinted on the anisotropic transparent solid material or when the crystal sphere is formed, as shown in FIG. 9, a different laser beam 45 irradiated to generate the void 13 is transmitted. It is preferable that the isotropic transparent solid material portion does not become the annular path 43 after the completion of the crystal sphere. Since the surface acoustic wave 41 propagates in the annular path 43, the portion affected by the laser light transmission is changed in quality so that the propagation is not affected.

  In addition, as described above, when the crystal sphere 3 is created by polishing from the polygonal column tip 2, the diameter of each crystal material having an initial cube or rough corner is set to the target crystal sphere 3. A size approximately 1.4 times the diameter is necessary, and a shape close to a true sphere is created under the relationship shown in FIG. Therefore, the gap marked for axial orientation recognition in the present invention must also be formed at a position that falls within the crystal sphere 3 targeted so as not to be lost during spheroid machining.

  As described below, the recording of the axial orientation by imprinting the gap 13 using an ultrashort pulse laser was performed on the wafer material 1 on which a crystal sphere was formed.

  FIG. 1 is a schematic view of a mechanism for marking a gap 13 inside the wafer material 1 using the ultrashort pulse laser generation control means 12.

  The prepared wafer material 1 is a 2-inch Z-cut quartz substrate having a thickness of 1.4 mm. With respect to this wafer material 1, as shown in FIG. 8, two points on the material which are on the XY plane and have the same YX coordinate but different coordinates in the X-axis direction are the crystal spheres obtained after the sphere processing. The XY direction position control means 47 and the Z direction position control means 48 were operated at the positions indicated on the X axis by marking all of them one by one while irradiating the laser beam 45. As shown in FIG. 1B, alignment is performed so that the focal point 49, which is a high energy density region generated by the focusing of the laser light 45 generated by the ultrashort pulse second laser generation control means 12, becomes the marking formation coordinates. Subsequently, the laser beam 45 is irradiated to form a gap 13 having a diameter of the order of micrometers. Here, the gap marking coordinates at each of the two positions were formed at positions that sandwiched the center of a cube having a side of 1.4 mm and were not scraped off during spherical processing.

  The ultrashort pulsed second laser used in the present invention is CPA-2001 manufactured by Clark MXR, and can be irradiated with a wavelength of 775 nm, an average maximum output of 1 W, and a repetition frequency of 1 kHz.

  The laser beam 45 emitted from the laser device passes through the optical system, and the focal point 49 is positioned at a predetermined position inside the wafer material 1 using a condenser lens. The alignment in the vertical and horizontal directions was performed on a stage group on which the wafer material 1 was mounted. A mechanism for irradiating the laser beam 45 by focusing the focus 49 of the laser beam 45 on a predetermined position with respect to the wafer material 1 using a software controller.

  After measuring and positioning the surface coordinates of the wafer material, the position was adjusted to a desired depth by moving the Z-axis stage. Thereafter, it was confirmed using a microscope that a gap 13 having a diameter of 1 μm to 5 μm could be formed inside the wafer material 1 by irradiation with a beam spot (beam waist diameter, focal point) of 10 μm, average output of 3 mW and 1 pulse.

  Through the above operation, all the divided portions in the wafer material 1 were marked, and the polygonal column chip 2 was cut out by a dicing apparatus. Here, the shape of the polygonal column chip is a cube.

  After roughing, the polishing was performed by spherical polishing with an Imahashi-type round ball processing machine. In this example, the surface of the wafer material was not left because it was cut into a cube, and therefore, sufficient polishing was performed to obtain the required spherical accuracy to obtain a true crystal crystal sphere having a diameter of 1 mm.

  The quartz crystal sphere 3 having a diameter of 1 mm thus obtained was processed into a spherical surface acoustic wave element 4. After applying the photoresist, it was set in an apparatus with a crystal ball rotating stage 15 shown in FIG. This apparatus measures the position of a gap 13 formed in the crystal sphere 3 from four directions with a confocal microscope camera 14, measures the direction of the crystal axis of the crystal sphere 3, and uses a crystal sphere rotation stage 15. Then, after correcting the crystal sphere 3 to face a predetermined direction, the interdigital electrode 42 pattern of the spherical surface acoustic wave element 4 was exposed.

The formation of the gap 13 has been described in the case of a Z-cut quartz wafer, but the same processing is possible for other crystal materials such as LiNbO ₃ , and according to the method of the present invention, the glassy The material can be processed as well as the transparent solid material described above.

  The present invention can be used for a delay line, an oscillation element and a resonance element for a transmitter, a filter for selecting a frequency, a chemical sensor, a biosensor, a remote tag, and the like.

It is the schematic which shows the stamp formation which suggests the axial direction using the laser beam based on this invention. It is the schematic which shows the Z-axis direction analysis means of the quartz crystal using the rotation of the polarization direction of the crystal known conventionally. It is explanatory drawing which shows an example of the crystal sphere formation method used by this invention. It is explanatory drawing which shows the example of the spherical surface acoustic wave element which concerns on this invention. It is explanatory drawing which shows the example of the marking coordinate to the anisotropic transparent solid material which concerns on this invention. It is explanatory drawing which shows the example of the marking coordinate to the anisotropic transparent solid material which concerns on this invention. It is a figure which shows the 1st example of the space | gap formation method by the ultrashort pulse laser which concerns on the Example of this invention. It is a figure which shows the 2nd example of the space | gap formation method by the ultrashort pulse laser which concerns on the Example of this invention. It is a figure which shows the example of the incident angle of the laser beam of the space | gap formation method by the ultrashort pulse laser which concerns on the Example of this invention. It is a figure which shows schematic structure of the apparatus which performs the space | gap position measurement for processing into the spherical surface acoustic wave element based on the Example of this invention, and coordinate-axis specification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... wafer material 2 ... polygonal-chip 3 ... crystal ball 4 ... spherical surface acoustic wave element 7 ... orientation flat 12 ... ultrashort pulse laser generation control means 13 ... Gap 14 ... Confocal microscope camera 15 ... Crystal rotation stage 16 ... Image analysis and crystal direction analysis means 41 ... Surface acoustic wave 42 ... Interdigital electrode 43 ... Circle Annular path 44 ... A portion 45 outside the annular region 45 ... Laser beam 46 ... Beam control optical means 47 ... XY direction position control means 48 ... Z direction position control means 49 ...・ Focus 50 ... Polarizing plate 51 ... Cut off

Claims (5)

  An anisotropic transparent solid material, wherein a solid material having transparency and anisotropy is engraved with an azimuth axis inside the solid material using a laser beam.   The anisotropic transparent solid material according to claim 1, wherein the laser beam is an ultrashort pulse laser having an instantaneous power of GW and a pulse width of 1 picosecond or less.   The anisotropic transparent solid material according to claim 1, wherein the stamp is a void.   The spherical surface acoustic wave element which has an inside stamp manufactured using the anisotropic transparent solid material in any one of Claims 1-3. A method for manufacturing a spherical surface acoustic wave device made of a spherical solid material having transparency and anisotropy, comprising at least the following steps 1 to 3, characterized in that an internally visible orientation A method for manufacturing a spherical surface acoustic wave element having an axis stamped thereon.
Step 1. An orientation that is visible with respect to at least one orientation inside the anisotropic transparent solid material by irradiating a laser beam to the anisotropic transparent solid material having a plane that maintains a certain angle with respect to one crystal orientation 1. Process of marking the shaft 2. Step of cutting the anisotropic transparent solid material into chips A step of processing the tip-shaped anisotropic transparent solid material into a spherical shape while leaving the azimuth axis engraved in step 1 inside

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