JP2016205925A - Holding jig for single cristal orientation measurement and production method of single cristal cylindrical block using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a holding jig for single crystal orientation measurement enabling an existing X-ray single crystal orientation measurement device to accurately measure a crystal orientation where a position of a principal surface of a single crystal is largely apart from a position of a wafer reference surface to be obtained, and a production method of a single crystal cylindrical block using the holding jig.SOLUTION: A holding jig 150 for single crystal orientation measurement used for measuring a crystal orientation with X-ray radiation, comprises: a crystal holding base 61 mounting and supporting a crystal 40; a rotary shaft 62 rotatably supporting the crystal holding base; and crystal holding base fixing means 90 and 100 fixing the crystal holding base that is rotated around the rotary shaft and in an inclined state.SELECTED DRAWING: Figure 1

Description

The present invention relates to a single crystal orientation measurement jig and a method of manufacturing a single crystal cylinder block using the same, and in particular, measures the orientation of a sapphire large single crystal using an X-ray orientation measurement device, and circles in a predetermined orientation. The present invention relates to a single crystal orientation measuring jig used when processing into a columnar block and a method of manufacturing a single crystal cylindrical block using the jig.

  The sapphire wafer is used as an LED (Light Emitting Diode) application, and its application as a blue-violet laser substrate used in a Blu-ray disc is being studied. The crystal orientation of the sapphire wafer depends on the crystal orientation obtained by slicing a large sapphire single crystal. Therefore, in order to manufacture a wafer having a desired crystal orientation, it is desirable to control the orientation when pulling up a large single crystal.

  As a method for producing a sapphire single crystal, a known crystal production method such as CZ (Czochralski) method or kilopros method can be used. When producing an a-axis oriented single crystal by the above-described production method, it is possible to produce a single crystal with few defects, but when producing a c-axis oriented single crystal, it is difficult to produce a single crystal with few defects. Has been.

  A sapphire single crystal is composed of an a-plane main surface and c-plane and m-plane representative side surfaces, and wafers used for LED applications have many c-plane standards. Therefore, in order to obtain a c-plane based wafer, it is necessary to cut out a large cylindrical single crystal having a substantially cylindrical shape or a substantially frustoconical shape from a side surface and process it into a cylindrical block.

  Therefore, in order to process a wafer using the a-axis-oriented sapphire large single crystal, first, the sapphire large single crystal is punched into a cylindrical block (for example, see Patent Document 1). In the method for producing a sapphire single crystal block described in Patent Document 1, since the c-plane can be determined to some extent by the crystal orientation of the seed surface in contact with the melt, the seed used when pulling up the large sapphire single crystal is used. When set to a machine tool to be machined, the c-plane determined to some extent is set upward. And after performing cylindrical block processing and performing end surface processing on the basis of a cylinder, cylindrical grinding is performed on the basis of surface orientation.

JP 2008-971 A JP 2003-254918 A

  However, in the state of a large single crystal, the c-plane that is the crystal side surface can be determined to some extent, but the c-plane cannot be accurately grasped. Therefore, it is necessary to grind the diameter at the time of hollowing out the cylindrical block so that a desired wafer size can be obtained even if grinding is performed in accordance with an accurate crystal orientation in the final cylindrical grinding. Therefore, when processing a cylindrical block, it is necessary to manufacture a slightly larger cylindrical block in consideration of a machining allowance, which is a major factor for reducing the yield of a wafer obtained from a large single crystal.

  FIG. 6 is a diagram showing an example of conventional block machining considering such machining allowance. As shown in FIG. 6, in order to obtain a cylindrical wafer 46 having a c-plane as a main surface from a cylindrical single crystal block 45, crystals of the main surface of the single crystal block 45 and the main surface of the cylindrical wafer 46 are obtained. In consideration of misalignment, it is necessary to cut out the single crystal block 45 including the machining allowance 47. Therefore, the yield of the wafer obtained from the large single crystal is reduced by the provision of the cutting allowance 47.

  On the other hand, in order to measure the azimuth plane of a single crystal, an azimuth measuring apparatus using X-rays is known (for example, see Patent Document 2). Such an azimuth measuring device integrally rotates an X-ray source and an X-ray detection means that can rotate around the ω axis, and an ω axis, an X-ray source, and an X-ray detection means about a χ axis that is substantially perpendicular to the ω axis. Χ moving means for moving. According to such an orientation measuring apparatus, when the main surface and the crystal orientation of the semiconductor wafer to be obtained are not greatly different from each other like a silicon single crystal, the crystal orientation can be accurately measured. However, the orientation measuring apparatus having the configuration described in Patent Document 2 can accurately set the crystal orientation as it is when the reference plane of the wafer is greatly different from the main surface of the single crystal, as in the case of a sapphire large single crystal. It cannot be measured.

  Therefore, the present invention enables accurate crystal orientation measurement using an existing X-ray single crystal orientation measuring apparatus even when the main surface of the single crystal and the reference plane of the wafer to be obtained are greatly different. It is an object of the present invention to provide a single crystal orientation measuring jig that can be used and a method of manufacturing a single crystal cylindrical block using the jig.

To achieve the above object, a single crystal orientation measurement jig according to one aspect of the present invention is a single crystal orientation measurement jig used when measuring crystal orientation by X-ray irradiation,
A crystal holding table capable of mounting and supporting the crystal;
A rotating shaft that rotatably supports the crystal holding table;
And holding table fixing means capable of rotating the crystal holding table around the rotation axis and fixing the crystal holding table in a state where the crystal holding table is inclined.

The method for producing a single crystal cylindrical block according to another aspect of the present invention includes a step of measuring the crystal orientation of a single crystal by X-ray irradiation using the single crystal orientation measurement jig,
Placing the single crystal whose crystal orientation is measured on a processing table of a single crystal cylindrical block manufacturing apparatus;
Adjusting the tilt of the processing table so that the single crystal can be processed in conformity with the measured crystal orientation;
And a grinding process of hollowing out a cylindrical single crystal cylindrical block from a side surface of the single crystal.

The method for producing a single crystal cylindrical block according to another aspect of the present invention includes a step of measuring the crystal orientation of a single crystal by X-ray irradiation using the single crystal orientation measurement jig,
Placing the single crystal of which the crystal orientation has been measured on a processing table of a single crystal cylindrical block manufacturing apparatus while the L-shaped mounting jig is mounted;
Adjusting the tilt of the processing table so that the single crystal can be processed in conformity with the measured crystal orientation;
And a step of grinding the cylindrical single crystal cylindrical block from the side surface of the single crystal.

  According to the present invention, it is possible to accurately measure a crystal orientation greatly different from the main surface of a single crystal.

It is a side view which shows an example of the jig | tool for single crystal orientation measurement which concerns on embodiment of this invention. It is a top view which shows an example of the jig | tool for single crystal orientation measurement which concerns on embodiment of this invention. It is the figure which showed the state which inclined the crystal holding | maintenance part of the inclination mechanism of the jig for single crystal orientation measurement which concerns on embodiment of this invention. FIG. 3A is a diagram showing a neutral state in which the crystal holding portion is not tilted. FIG. 3B is a view showing a state in which the 45 ° crystal holding part is tilted to the left side. FIG. 3C is a view showing a state in which the 45 ° crystal holding part is tilted to the right side. It is the figure which showed an example of the single-crystal block manufacturing apparatus for hollowing out a single crystal and forming a cylindrical block. It is the figure which compared and showed the processing of the cylindrical block which concerns on the conventional comparative example, and the processing of the cylindrical block using the jig | tool for single-crystal orientation measurement which concerns on a present Example. Fig.5 (a) is the figure which showed the process of the cylindrical block which concerns on a prior art example. FIG.5 (b) is the figure which showed the process of the cylindrical block using the jig | tool for single crystal orientation measurement which concerns on a present Example. It is the figure which showed an example of the block process which considered the conventional machining allowance.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a side view showing an example of a single crystal orientation measuring jig 150 according to an embodiment of the present invention. FIG. 2 is a top view showing an example of the single crystal orientation measuring jig 150 according to the embodiment of the present invention. In this embodiment, an example using an X-ray single crystal orientation measuring device (2991G2) manufactured by Rigaku Corporation will be described as an X-ray single crystal orientation measuring device. However, the single crystal orientation measuring jig 150 according to this embodiment is applied not only to the above-described X-ray single crystal orientation measuring device (2991G2) but also to various single crystal orientation measuring devices capable of measuring the orientation of the single crystal. Is possible.

  1 and 2, the part drawn with a one-dot chain line is a constituent element of the X-ray single crystal orientation measuring apparatus 10, and the part drawn with a solid line is a constituent element of the crystal orientation measuring apparatus according to the present embodiment. .

  As shown in FIG. 1, a base plate 20 is fixed with reference to a projection 12 of the θ stage at the center of the rotary stage 11 of the X-ray single crystal orientation measuring apparatus 10. A structure having a roller 30 for reducing the load applied to the rotary stage 11 is adopted. The base plate 20 is provided with a fixed plate 24 provided with a slide guide 23 composed of an upper guide 21 and a lower guide 22. As shown in FIGS. 1 and 2, when the large single crystal 40 is set, the large single crystal 40 has a structure that can be slid and moved to the end face of the measuring device on which the base plate 20 extends.

  As shown in FIG. 1, the large single crystal 40 is bonded to an L-shaped jig 50, and the L-shaped jig 50 is bolted to the crystal holding portion 61 of the tilt mechanism 60. The tilt mechanism 60 is placed on a dedicated carriage on which a roller is installed, and carries the large single crystal 40 to the vicinity of the fixed plate 24 that slides to the end face of the orientation measuring device. The tilt mechanism 60 includes, in addition to the crystal holding unit 61 that holds the single crystal via the L-shaped jig 50 described above, a rotation shaft 62 that rotatably supports the crystal holding unit 61, a crystal holding unit 61, and a rotation shaft 62. And a support portion 63 that supports the. In addition, the crystal holding unit 61 includes a bottom plate 61 a that supports the large single crystal 40 from below and a side plate 61 b that supports the large single crystal 40 from the side.

  The tilt mechanism 60 may have a structure in which, for example, a bearing is installed on the bottom plate of the support portion 63 (none is shown), and the large single crystal 40 that is a heavy object can be easily slid. The fixing plate 24 and the tilting mechanism 60 are positioned by the bolts 26, but the fixing plate 24 is formed with a recess in which a bearing can be engaged in the vicinity of the fixing position of the tilting mechanism 60. The tilt mechanism 60 may have a structure in which both the surface contact and the tilt mechanism 60 are positioned and fixed.

  As shown in FIG. 2, the tilt mechanism 60 fixed to the fixing plate 24 is slid to the X-ray single crystal orientation measurement position and fixed by the lock lever 25.

  As shown in FIGS. 1 and 2, the orientation measurement position of the large single crystal 40 is determined by a positioning stopper 71 of the crystal positioning mechanism 70 installed on the opposite surface of the fixed plate 24, and the crystal positioning mechanism 70 also has a slide guide. 72 and positioning stopper 71 are installed. At the initial setting, a calibration plate is installed in place of the crystal positioning mechanism 70, the position of the positioning stopper 71 is determined by checking the X-ray position.

  Thereby, the measurement from the next time can be easily performed by moving the position of the crystal positioning plate 70 to a position where the large single crystal 40 and the positioning stopper 71 are in contact with each other. When the positioning of the large single crystal 40 is completed, the crystal positioning mechanism 70 is preferably slid to the rear of the apparatus and fixed.

  When the handle 13 of the X-ray single crystal orientation measuring device main body is rotated, the rotary stage 11 is rotated, and the orientation measurement position of the large single crystal 40 is positioned at a position where the X-ray near the θ angle of 21 ° reaches a peak. .

  FIG. 3 is a view showing a state in which the crystal holding portion 61 of the tilt mechanism 60 of the single crystal orientation measuring jig 150 according to the embodiment of the present invention is tilted. FIG. 3A is a diagram showing a neutral state in which the crystal holding unit 61 is not tilted, and FIG. 3B is a diagram showing a state in which the 45 ° crystal holding unit 61 is tilted to the left side. FIG. 3C is a view showing a state in which the 45 ° crystal holding portion 61 is inclined to the right side.

  The tilting mechanism 60 to which the large single crystal 40 is fixed has a rotation shaft 62 at the same height as the X-ray irradiation unit of the orientation measuring device main body of the side plate 61b of the crystal holding unit 61, and tilts by 45 ° to the left and right. It has a possible structure. Since moment is applied to the rotating shaft 62, an R guide 80 is attached below the rotating shaft 62 as the support. The R guide 80 is a rotation direction guide means for guiding the rotation movement or the inclination movement of the bottom plate 61 a of the crystal holding unit 61 along the rotation direction of the rotation shaft 62. For example, the R guide 80 has a structure that regulates the moving direction of grooves, rails, and the like, and is configured such that the bottom plate 61a and the side plates 61b of the crystal holding unit 61 are engaged with each other to guide the bottom plate 61a.

  As shown in FIG. 3B, the positioning when tilted 45 ° to the left is performed by the index plunger 90 and is fastened and fixed by the fixing screw 100. That is, the crystal holding part 61 is positioned and fixed at a predetermined inclination angle by the cooperation of the index plunger 90 and the fixing screw 100. At this time, if the orientation of the single crystal is measured, it can be measured how many times the plane orientation of the large single crystal 40 is deviated from the x-axis, and the crystal orientation in the x-axis direction can be grasped.

  Next, as shown in FIG. 3C, the grip 110 is held, the fixing screw 100 is removed, the index plunger 90 is released, and the crystal holding portion 61 of the tilt mechanism 60 is moved in the reverse direction (right direction). The fixing screw 100 is similarly fastened and fixed by tilting 45 °. At this time, if the orientation measurement of the large single crystal 40 is performed, it can be measured how many times the plane orientation of the large single crystal 40 is shifted from the y-axis, and the crystal orientation in the y-axis direction can be grasped.

  Originally, the azimuth | direction measurement of a cylindrical block is performed by measuring the x-axis and y-axis of a block end surface, and confirming the deviation | shift of an azimuth | direction. When trying to measure a sapphire large single crystal 40 by this method, the single crystal must be installed vertically and horizontally. However, paying attention to the biaxial measurement, it is measured by tilting 45 ° in one direction of rotation. Then, it becomes possible to measure by tilting 90 ° in the opposite direction.

  FIG. 4 is a diagram showing an example of a single crystal block manufacturing apparatus 250 for hollowing out a single crystal to form a cylindrical block. As such a single crystal block manufacturing apparatus 250, for example, an apparatus described in Japanese Patent Application Laid-Open No. 2008-971 can be used. By using the orientation measuring jig according to the present embodiment, a single crystal block manufacturing apparatus 250 can be used. Since the azimuth is accurately measured, block machining is performed utilizing the measured azimuth.

  As shown in FIG. 4, the single crystal block manufacturing apparatus 250 has a configuration in which an inclined circular table 220 is set on a slide table 210. The tilted circular table 220 is a tiltable table, and the tilt angle of the processing table 221 on which the large single crystal 40 is placed can be adjusted. The tilt angle of the processing table 221 can be adjusted by changing the tilt angle of the tilt support portion 222 with the tilt direction handle 223. Further, the processing table 221 can be rotated in the horizontal direction by the rotation direction handle 224.

  Then, the large single crystal 40 measured using the single crystal orientation measuring jig 150 according to the embodiment of the present invention is fixed on the processing table 221 while being bonded to the L-shaped jig 50. Next, after adjusting the inclination of the processing table 221 to be adapted to the orientation measurement value, if the core bit 140 is lowered and punching is performed, a cylindrical block with almost no crystal orientation deviation can be manufactured. .

〔Example〕
Next, an example in which a single crystal orientation measurement is performed using a single crystal orientation measurement jig according to an embodiment of the present invention and a single crystal cylindrical block is manufactured based on the measurement result will be described.

  In order to finish a cylindrical shape with a diameter of 3 inches (φ76.2 mm) by cylindrical grinding, initially, the diameter of the core bit was used in the single crystal cylindrical block manufacturing apparatus, but the single crystal orientation according to this example was used. By using a measuring jig, cylindrical grinding can be performed with a core bit having a diameter of φ80 mm.

  This means that the grinding amount during cylindrical grinding has been reduced by about 75%. Also, when processing a cylindrical block from a large single crystal, it is possible to process from 3 to 5 pieces so far.

  FIG. 5 is a diagram comparing the processing of a conventional cylindrical block according to a comparative example and the processing of a cylindrical block using the single crystal orientation measuring jig according to the present embodiment. FIG. 5A is a diagram showing the processing of the cylindrical block according to the conventional example, and FIG. 5B shows the processing of the cylindrical block using the single crystal orientation measuring jig according to the present example. It is a figure.

  As shown in FIG. 5A, conventionally, since it was necessary to grind a φ90 mm cylindrical block 45 from the large single crystal 40, only three cylindrical blocks 45 could be obtained.

  On the other hand, as shown in FIG. 5B, when the single crystal orientation measuring jig according to the present embodiment is used, the crystal orientation can be measured accurately. (See FIG. 6) is not included or can be very small even if included, and it is sufficient to grind the cylindrical block 41 of φ80 mm. In this case, as many as five cylindrical blocks 41 can be obtained from one large single crystal 40, and the yield can be greatly improved.

  Thus, by using the single crystal orientation measurement jig according to the embodiments and examples of the present invention, it is possible to accurately grasp the direction to be extracted into the cylindrical block at the time of orientation measurement. The diameter of the block can be set near the standard value, and the cylindrical grinding time can be shortened. Further, a large number of cylindrical block processed products can be obtained from the sapphire large single crystal, and the wafer yield can be improved.

  The preferred embodiments and examples of the present invention have been described in detail above. However, the present invention is not limited to the above-described embodiments and examples, and the above-described embodiments and examples can be performed without departing from the scope of the present invention. Various modifications and substitutions can be made to the embodiments.

DESCRIPTION OF SYMBOLS 10 X-ray single crystal orientation measuring device 20 Base 23, 72 Slide guide 40 Large crystal 50 L-shaped jig 60 Inclination mechanism 61 Crystal holding part 61a Bottom plate 61b Side plate 62 Rotating shaft 63 Support part 70 Crystal positioning mechanism 71 Crystal positioning stopper 80 R guide 90 Index plunger 100 Fixing screw 110 Grip 150 Single crystal orientation measuring jig 220 Tilt table 221 Processing table 230 Core bit 250 Single crystal cylinder block manufacturing device

Claims (8)

A single crystal orientation measurement jig used when measuring crystal orientation by X-ray irradiation,
A crystal holding table capable of mounting and supporting the crystal;
A rotating shaft that rotatably supports the crystal holding table;
A jig for measuring a single crystal orientation, comprising: a holding table fixing means capable of rotating the crystal holding table around the rotation axis and fixing the crystal holding table in a state where the crystal holding table is inclined.   The single crystal orientation measuring jig according to claim 1, wherein the crystal holding table has a substantially L-shape, and includes a bottom plate that supports a lower surface of the crystal and a side plate that supports a side surface of the crystal.   The single crystal orientation measuring jig according to claim 1, wherein the holding base fixing means includes a positioning shaft and a fixing screw for fixing the positioning shaft. The support plate further supports the rotating shaft and is provided substantially parallel to the side plate of the crystal holding table,
4. The single crystal orientation measurement jig according to claim 1, wherein the support plate and the side plate have a guide mechanism that engages with each other to guide rotation around the rotation axis. 5.   The single crystal orientation measurement jig according to claim 4, wherein the guide mechanism includes a groove or a rail along a rotation direction around the rotation axis. An L-shaped mounting jig that can be bonded to the crystal and can be fixed to the crystal holding table,
The single crystal orientation measuring jig according to claim 1, wherein the crystal is supported on the crystal holding table via an L-shaped mounting jig bonded to the crystal. Using the single crystal orientation measurement jig according to any one of claims 1 to 5 to measure the crystal orientation of the single crystal by X-ray irradiation;
Placing the single crystal whose crystal orientation is measured on a processing table of a single crystal cylindrical block manufacturing apparatus;
Adjusting the tilt of the processing table so that the single crystal can be processed in conformity with the measured crystal orientation;
And a step of grinding the cylindrical single crystal cylindrical block from the side surface of the single crystal. Using the single crystal orientation measuring jig according to claim 6 to measure the crystal orientation of the single crystal by X-ray irradiation;
Placing the single crystal of which the crystal orientation has been measured on a processing table of a single crystal cylindrical block manufacturing apparatus while the L-shaped mounting jig is mounted;
Adjusting the tilt of the processing table so that the single crystal can be processed in conformity with the measured crystal orientation;
And a step of grinding the cylindrical single crystal cylindrical block from the side surface of the single crystal.

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