WO2017158655A1 - Dispositif de mesure de creuset, procédé de mesure de creuset et procédé de production de creuset - Google Patents

Dispositif de mesure de creuset, procédé de mesure de creuset et procédé de production de creuset Download PDF

Info

Publication number
WO2017158655A1
WO2017158655A1 PCT/JP2016/001613 JP2016001613W WO2017158655A1 WO 2017158655 A1 WO2017158655 A1 WO 2017158655A1 JP 2016001613 W JP2016001613 W JP 2016001613W WO 2017158655 A1 WO2017158655 A1 WO 2017158655A1
Authority
WO
WIPO (PCT)
Prior art keywords
silica glass
glass crucible
laser light
crucible
light
Prior art date
Application number
PCT/JP2016/001613
Other languages
English (en)
Japanese (ja)
Inventor
俊明 須藤
忠広 佐藤
賢 北原
修司 飛田
江梨子 北原
Original Assignee
株式会社Sumco
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 株式会社Sumco filed Critical 株式会社Sumco
Priority to PCT/JP2016/001613 priority Critical patent/WO2017158655A1/fr
Priority to TW106107890A priority patent/TW201738528A/zh
Publication of WO2017158655A1 publication Critical patent/WO2017158655A1/fr

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B15/00—Single-crystal growth by pulling from a melt, e.g. Czochralski method
    • C30B15/10—Crucibles or containers for supporting the melt
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
    • C30B29/02—Elements
    • C30B29/06—Silicon
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/47—Scattering, i.e. diffuse reflection

Definitions

  • the present invention relates to a crucible measuring apparatus, a crucible measuring method, and a crucible manufacturing method for measuring the layer structure in the thickness direction of a silica glass crucible.
  • Silica glass crucibles used for silicon single crystal pulling for example, by providing a transparent layer and a bubble-containing layer, etc., reduce the occurrence of brown ring during silicon single crystal pulling, and make it easier to control the heat, The crystallinity of the silicon single crystal is improved.
  • the silica glass crucible is exposed to a high temperature of about 1410 ° C. or higher, which is the melting temperature of silicon.
  • a high temperature of about 1410 ° C. or higher, which is the melting temperature of silicon.
  • the bubble density in the bubble-containing layer is not uniform, for example, when the bubble-containing layer is composed of layers having a plurality of different bubble densities, the layers having different bubble densities have different coefficients of thermal expansion, so the silicon melting temperature is high.
  • the silica glass crucible may be deformed or damaged depending on the shape of the silica glass crucible, the mass of the silicon solution, the time of exposure to high temperature, and the like.
  • the silica glass crucible when the silica glass crucible is composed of a single layer in the thickness direction, the constituent atoms of the silica glass are connected to the thickness direction of the silica glass crucible in a network shape, and the same silica network is formed in the layer. It becomes a structure. Therefore, once a crack occurs in the silica glass crucible and the network-like bond is broken, the crack expands to a wide area of the crucible, and as a result, the silica glass crucible may break.
  • the silica glass crucible is composed of a plurality of transparent layers and bubble-containing layers in the thickness direction, or the silica glass crucible is composed of a plurality of transparent layers or bubble-containing layers in the thickness direction.
  • the expansion of cracks stops at the interface portion.
  • the layer structure in the thickness direction of the silica glass crucible has a great influence on the heat resistance and impact resistance, it is important to measure the layer structure.
  • silica glass is transparent, when the size of the bubbles is fine, these layer structures may not be sufficiently observed visually. Further, in the transparent layer, a defect such as a fine scratch may exist even if no abnormality is observed by visual inspection or the like.
  • silica glass crucible layer structures and defects such as fine scratches may cause defects in the silicon ingot when exposed to silicon melt during the pulling of the silicon single crystal. It is important in the design and quality control of silica glass crucibles to measure defects such as fine scratches.
  • silica glass crucibles for pulling silicon single crystals are generally manufactured by a rotational mold method, it is difficult to control characteristics such as shape and interior.
  • the manufactured silica glass crucible is subjected to the following measurement, but it is performed in a non-contact manner because it is necessary to keep the inner surface of the silica glass crucible clean.
  • the structure, defects, etc. of the layer in the thickness direction of the manufactured silica glass crucible have been confirmed by destructive inspection after extracting the manufactured silica glass crucible.
  • visual inspection uses transmitted light or the like as in the case of observing an object with an optical microscope or the like.
  • a silica glass crucible sliced on a line connecting a light source and an observation point is installed and irradiated with light, and the transmitted light of the silica glass crucible is visually or imaged to detect defects in the glass. .
  • Patent Document 3 ultraviolet light having a wavelength shorter than 365 nm is irradiated on the wall surface of the silica glass crucible, and the number of fluorescent spots of the generated light having a wavelength of 400 nm to 600 nm is measured.
  • the layer structure cannot be detected. Further, for example, when a defect or the like is very small, the intensity of diffracted light or the like by the defect is not sufficient, and the defect or the like may not be detected because it is hidden by transmitted light from a light source. Since the inspection methods described in Patent Documents 1 to 3 are methods for measuring the shape of the silica glass crucible and the state near the inner surface, the inside of the transparent layer or the bubble-containing layer in the thickness direction of the silica glass crucible that cannot be detected by visual inspection or the like A defect such as a further layer structure or a fine scratch in the transparent layer existing inside could not be detected.
  • An object of the present invention is to provide a technique for easily and non-destructively detecting a further layer structure or a defect or the like existing inside a transparent layer or a bubble-containing layer that could not be detected conventionally.
  • the inventor enters laser light on the upper surface of the silica glass crucible or the inner surface near the upper end of the silica glass crucible, and observes scattered light at each position in the thickness direction inside the side wall of the silica glass crucible.
  • the inventors have found that there are further layer structures, defects, etc. existing inside the transparent layer or bubble-containing layer that could not be detected by the conventional method, and invented a method that can be easily and non-destructively observed.
  • the layer structure and defects inside the transparent layer or the bubble-containing layer can be observed by a nondestructive and simple method.
  • the silica glass crucible which has a certain kind of defect etc. can be discriminate
  • the laser light scattering state refers to the state of spread and intensity of the laser scattered light.
  • the light transmission layer is a transparent layer and refers to a region where no defect such as a scratch exists.
  • a layer having defects such as scratches in the bubble-containing layer or the transparent layer is referred to as a light scattering layer.
  • the silica glass crucible in the present embodiment includes a cylindrical side wall portion (straight barrel portion) having an opening at the upper end, a curved bottom portion, a corner portion connecting the side wall portion and the bottom portion and having a larger curvature than the bottom portion. It has the shape provided with. Moreover, the upper end surface of the side wall part of the silica glass crucible is formed as an annular flat surface. Further, the silica glass crucible includes, for example, a transparent layer in which bubbles cannot be observed based on visual observation or image data, and a bubble-containing layer in which bubbles are observed, from the inner surface to the outer surface of the silica glass crucible. It is comprised with the layer of.
  • the silica glass crucible in the present embodiment is manufactured by using, for example, a rotational mold method.
  • the rotational mold method is a method for producing a silica glass crucible by depositing silica powder in a rotating mold (made of carbon) and arc melting the deposited silica powder layer. Since the shape in the vicinity of the opening end of the silica glass crucible is likely to be uneven, the opening end of the silica glass crucible by the rotational molding method is cut with a predetermined width to align the shape of the opening end.
  • the silicon single crystal is produced, for example, by rotating the silica glass crucible, melting polycrystalline silicon inside, bringing the seed crystal into contact with the silicon melt, and pulling up the seed crystal after necking treatment. Is done.
  • the silica glass crucible is used every time the silicon single crystal is pulled. That is, the silica glass crucible needs to be prepared separately for each pulling of the silicon single crystal.
  • the ratio of the thickness of the bubble-containing layer to the thickness of the transparent layer is 0.7 in the middle portion between the upper end and the lower end of the portion formed in the vertical direction of the silica glass crucible.
  • the roundness of the inner surface of the crucible and the roundness of the outer surface of the crucible are both 0.4 or less with respect to the maximum thickness M at the same measurement height as the roundness.
  • a high crystallization rate can be realized during crystal pulling (Japanese Patent Laid-Open No. 2009-286651).
  • the silica glass crucible has a transparent layer for the purpose of improving the quality of the silicon single crystal that can be reduced by reducing the factors of occurrence of the brown ring, and facilitating thermal control during the pulling of the silicon single crystal.
  • a bubble-containing layer is used.
  • the bubble-containing layer that appears to be composed of one layer when visually observed may actually be composed of a plurality of layer structures.
  • Such a defect may cause redoing of the pulling of the silicon single crystal and damage of the silica glass crucible during pulling. Therefore, it is desirable to discriminate the silica glass crucible having such defects in advance.
  • a silica glass crucible having a defect and a silica glass crucible having no defect appear to be a silica glass crucible having a transparent layer and a bubble-containing layer. For this reason, there has been a problem that a silica glass crucible having a problem with the layer structure in the thickness direction of the silica glass crucible cannot be discriminated in advance by visual observation or the like.
  • the layer structure in the thickness direction of the silica glass crucible cannot be determined in advance by visual inspection. Therefore, it is conceivable to measure the layer structure in the thickness direction of the manufactured silica glass crucible using a technique for measuring the silica glass crucible as described in Patent Document 1 and Patent Documents 2 to 4.
  • a technique for measuring the silica glass crucible as described in Patent Document 1 and Patent Documents 2 to 4.
  • image analysis is performed in the thickness direction using the method described in Patent Document 1
  • the entire silica glass crucible is determined. It will be necessary to measure at each point in the thickness direction over the circumference, which is very laborious and time consuming.
  • Patent Documents 2 to 4 are techniques for measuring the state of the inner surface of the silica glass crucible. Therefore, with the techniques of Patent Documents 2 to 4, the structure of the layer in the thickness direction of the silica glass crucible could not be confirmed. As described above, in the techniques such as Patent Documents 1, 2 to 4, it is impossible to measure the layer structure in the thickness direction of the manufactured silica glass crucible, or it takes a lot of time and effort to measure. There was a problem. Therefore, the structure of the layer in the thickness direction of the manufactured silica glass crucible has generally been confirmed by extracting a part of the manufactured silica glass crucible and performing a destructive inspection.
  • An apparatus for evaluating a silica glass crucible is an apparatus for evaluating a silica glass crucible manufactured by a rotational molding method, and includes a cylindrical straight body portion having an opening at an upper end, a curved bottom portion, and An upper end surface of a silica glass crucible or a silica glass crucible having a corner portion connecting the side wall portion and the bottom portion and having a curvature larger than that of the bottom portion, and wherein the upper end of the straight body portion is formed flat.
  • the scattering state of each position in the thickness direction inside the silica glass crucible side wall of the laser light incident on the inner surface near the upper end is measured.
  • a crucible measuring method includes a cylindrical straight body having an opening at an upper end to be measured, a curved bottom, the side wall, and the bottom. And a corner portion having a curvature larger than that of the bottom portion, and laser light is emitted to the upper end surface of the silica glass crucible or the inner surface near the upper end portion of the silica glass crucible where the upper end of the straight body portion is formed flat. And the structure of measuring the scattering condition of each position of the thickness direction inside the silica glass crucible side wall part of the laser light incident in the silica glass crucible is adopted.
  • a laser beam such as a semiconductor laser or a solid laser is emitted in the thickness direction from the inside or outside of the silica glass crucible near the upper end of the silica glass crucible.
  • the laser light incident on the silica glass crucible is transmitted or partially scattered depending on the structure of the layer in the thickness direction inside the side wall of the silica glass crucible.
  • the laser light incident on the side wall of the silica glass crucible is transmitted through the light transmission layer without being scattered or reflected.
  • the laser light is scattered in the light scattering layer.
  • the scattering state of the laser light entering the silica glass crucible is photographed using, for example, a camera, and the scattering state at each position in the thickness direction of the silica glass crucible is measured.
  • the laser light incident on the silica glass crucible causes various scattering situations such as transmission or partial scattering depending on the structure of the silica glass crucible (transparent layer, bubble-containing layer, presence or absence of defects, etc.). Therefore, image data corresponding to the layer structure in the thickness direction of the silica glass crucible can be acquired by photographing the end face of the silica glass crucible. By analyzing the image data, the layer structure in the thickness direction of the silica glass crucible can be continuously measured, and the layer structure in the thickness direction of the silica glass crucible can be measured easily and non-destructively.
  • the laser light incident into the silica glass crucible is scattered by any defects such as scratches even in the transparent layer, so by measuring the scattering of the laser light, Defects in the transparent layer that cannot be detected can be detected. It is also possible to measure whether or not a light transmission layer having a sufficient thickness necessary for pulling up the silicon single crystal is formed on the innermost surface side of the silica glass crucible.
  • the layer structure of the thickness direction of a silica glass crucible such as the presence or absence of a light transmissive layer, and the thickness of a light transmissive layer, can be measured easily nondestructively.
  • the incident laser light is scattered, and scattered light reflecting the layered structure is generated, so that the layer structure is known by measuring the scattered light.
  • the scattered light intensity of the laser light is uniform within a certain range, it can be seen that the light scattering layer is composed of one layer in the thickness direction of the crucible.
  • the bubble-containing layer When a plurality of layers are included in the bubble-containing layer, there may be a problem in the strength of the silica glass crucible due to the difference in the coefficient of thermal expansion of each layer. Therefore, by making the bubble-containing layer as a single layer, it is possible to reduce the risk of breakage of the silica glass crucible due to the difference in coefficient of thermal expansion. In order to reduce the breakage of the silica glass crucible due to the difference in thermal expansion coefficient or the like, it is desirable that the bubble-containing layer does not include a plurality of structures. That is, as described above, by measuring the layer structure of the light scattering layer or the bubble-containing layer, it is possible to determine a silica glass crucible with a low possibility of breakage due to a difference in coefficient of thermal expansion.
  • the thickness of the light scattering layer and the shape of the boundary between the light transmission layer and the light scattering layer can be measured, and a silica glass crucible or light transmission layer having a desirable light scattering layer thickness can be used.
  • a silica glass crucible having a desirable shape at the boundary interface with the light scattering layer can be identified.
  • the silicon melt interface is adjusted to be at the same position with respect to the heater of the silicon pulling device, and the crucible is controlled to move upward as the crystal pulling proceeds.
  • the temperature of the silicon single crystal growth part that is, the boundary between the melt and the crystal where the silicon melt becomes the silicon single crystal is the melting point of silicon, and this boundary part is stabilized. In order to achieve this, very delicate temperature control is required.
  • the silica glass crucible is composed of only a transparent layer, when the silicon melt in the silica glass crucible is heated with a heater, the radiant heat from the heater passes through the silica glass crucible and is directly transmitted to the silicon melt interface. Therefore, temperature control may be difficult.
  • a bubble-containing layer is provided outside the transparent layer, and the bubble-containing layer has an appropriate thickness. Therefore, by measuring the thickness of the light scattering layer, it is possible to discriminate a silica glass crucible that can easily perform appropriate temperature control.
  • the laser light incident in the silica glass crucible is scattered at the interface formed in the thickness direction of the silica glass crucible.
  • silica glass crucibles have the same silica network structure in the same layer. Therefore, once a crack occurs, the crack does not stop in the middle but expands in the layer, and the silica glass crucible may break. On the other hand, if there is an interface in the thickness direction, the structure of the silica network in each layer is different, so that the expansion of cracks stops at the interface portion, and the cracking of the silica glass crucible due to the expansion of cracks can be prevented.
  • a desired layer structure can be obtained by annealing a silica glass crucible at a temperature equal to or higher than the fictive temperature. Therefore, by selecting the silica glass crucible according to the above invention and performing an annealing treatment, it is possible to manufacture a crucible that is difficult to break.
  • Layer structure in the thickness direction of the silica glass crucible by emitting laser light from the end face direction of the silica glass crucible to each position in the thickness direction of the silica glass crucible and measuring Raman scattering generated according to the emitted laser light Can be grasped. That is, as an alternative to the above process, the Raman scattering generated according to the incident laser beam may be measured.
  • the crucible measuring device is configured such that the light emitting unit emits the laser light from the inside of the silica glass crucible toward the thickness direction of the silica glass crucible, and the scattering state measuring unit is configured to perform measurement. Measures the scattering state of the laser beam in the thickness direction inside the side wall of the silica glass crucible from the annular end surface around the upper end opening of the portion of the target silica glass crucible where the laser beam is incident by the light emitting part You may comprise.
  • the invention of the crucible measuring method is an annular structure around the upper end opening where the laser light is emitted in the thickness direction of the silica glass crucible from the inside to the outside of the silica glass crucible, and the laser light of the silica glass crucible enters. It is good also as a structure which measures the condition of the scattered light of each position along the thickness direction inside the silica glass crucible side wall part of a laser beam from the end surface direction.
  • a laser light source is installed inside the silica glass crucible naturally cooled so as to emit laser light from the inside of the crucible toward the thickness direction of the silica glass crucible.
  • the present invention may be configured such that the state of scattering of the laser light incident into the silica glass crucible is photographed by using a camera or the like from the annular end surface direction around the upper end opening of the silica glass crucible.
  • Laser light is incident from the inside to the outside of the silica glass crucible, and various scattering situations occur in the silica glass crucible. Therefore, when the scattering state of the laser light incident on the silica glass crucible is photographed from the end face direction of the silica glass crucible, image data corresponding to the layer structure in the thickness direction of the silica glass crucible can be acquired. By analyzing the image data, the structure of the layer in the thickness direction of the silica glass crucible can be easily measured without destruction, and a silica glass crucible having a desired quality can be discriminated.
  • Laser light is emitted from the inside of the silica glass crucible toward the thickness direction of the silica glass crucible, and the scattering state of the laser light inside the silica glass crucible side wall portion is measured from the end surface direction, whereby the layer in the thickness direction of the silica glass crucible
  • the thickness of the light transmission layer can be easily measured without breaking.
  • the crucible measuring device includes an illumination unit that irradiates the silica glass crucible with light having a predetermined wavelength corresponding to the wavelength of the laser light emitted from the light emitting unit, and the scattering state measurement unit includes the illumination unit You may comprise so that the scattering condition of the said laser beam may be measured under the irradiation of the light by a part.
  • the step of measuring the scattering state of the laser light irradiates the silica glass crucible with illumination light having a predetermined wavelength corresponding to the wavelength of the emitted laser light, and the laser light is irradiated under the illumination light irradiation. It is good also as a structure which measures a scattering condition.
  • the scattering state of the laser light can be made clearer.
  • the structure of the layer in the thickness direction of the silica glass crucible can be measured with high accuracy, and the silica glass crucible having a desirable layer structure in the thickness direction can be easily determined without destruction.
  • the crucible measuring apparatus may be configured such that the light emitting unit emits a horizontal laser as the laser light.
  • the present invention may include a step of emitting a horizontal laser to the silica glass crucible and measuring a scattering state at each position in the thickness direction of the silica glass crucible of the incident horizontal laser.
  • a horizontal laser is a line laser that is horizontal to the ground. According to this configuration, a horizontal laser is incident on the silica glass crucible with respect to the silica glass crucible, and various laser light scattering situations according to the structure of the silica glass crucible over a wide range are photographed with an optical camera or the like. Image data can be acquired.
  • the layer structure in the thickness direction of the silica glass crucible in a wide range where the laser beam in the horizontal direction as described above is incident can be efficiently formed at the same time. It can be measured.
  • the silica glass crucible is manufactured by depositing silica powder on a rotating carbon mold and arc melting the deposited silica powder layer. Therefore, the layer structure of the transparent layer or the bubble-containing layer is symmetric with respect to the central axis of the crucible. On the other hand, since silica powder accumulates, the symmetry of the layer structure is not seen in the height direction of the silica glass crucible. Therefore, in order to grasp the characteristics of the silica glass crucible, it is more important to know the distribution of the layer structure in the height direction.
  • the layer structure in the crucible height direction and the layer structure in the bubble-containing layer can be known in detail.
  • the vertical laser refers to a vertical line laser (for example, a horizontal laser tilted by 90 degrees). Furthermore, by using a cross-line laser, it is possible to combine the advantages of a horizontal laser and a vertical laser.
  • the angle may be arbitrary), for example, it is possible to determine at which depth a defect exists. It will be possible.
  • the present invention can use various lasers.
  • the crucible measuring device is configured such that the light emitting unit emits laser light to each position in the thickness direction of the silica glass crucible from the end surface direction of the silica glass crucible, A configuration is adopted in which Raman scattering generated according to the laser light emitted from the light emitting unit is measured at each position as the scattering state of the laser light.
  • the laser light is emitted from the end face direction of the silica glass crucible to each position in the thickness direction of the silica glass crucible, and the Raman scattering generated according to the emitted laser light is changed to the scattering state of the laser light. It is good also as a structure of measuring at each position.
  • scattered light from a silica glass crucible is removed through a Rayleigh light removal filter, and then dispersed through a spectroscope such as a diffraction grating and detected using a detector or the like. Thereafter, the information is converted into a Raman shift using an information processing apparatus or the like and displayed.
  • a plurality of peaks such as a peak attributed to a planar four-membered ring and a peak attributed to a planar three-membered ring are measured.
  • the structure of the silica network is different in each layer, and thus the wave number value of each peak of the Raman shift varies at each position in the thickness direction. . Therefore, the layer structure of each layer can be measured by measuring the Raman shift at each position in the thickness direction of the silica glass crucible.
  • the light emitting unit is configured to emit laser light over the entire circumference of the silica glass crucible at a predetermined interval
  • the scattering state measuring unit is configured to emit the light emitting unit. The laser beam scattering state according to the laser beam emitted from the unit is respectively measured.
  • the present invention may be configured such that laser light is emitted over the entire circumference of the silica glass crucible at predetermined intervals, and the scattering state of the laser light according to the emitted laser light is measured. Good.
  • the laser light source when laser light is emitted from the inside of the silica glass crucible in the thickness direction of the silica glass crucible, the laser light source is rotated in a state where the laser light is emitted, so that the entire circumference of the silica glass crucible is obtained. Laser light can be incident.
  • This configuration makes it possible to easily measure the structure in the thickness direction of the entire circumference of the silica glass crucible, and to determine the silica glass crucible in which no defect is detected over the entire circumference of the silica glass crucible.
  • Example [Embodiment 1] A crucible measuring apparatus and a crucible measuring method according to a first embodiment of the present invention will be described with reference to FIGS.
  • the figure shows an example of the configuration of the crucible measuring apparatus.
  • 2 to 4 are diagrams illustrating an example of a state where laser light is incident on a silica glass crucible when measured from the end surface direction.
  • FIG. 5 is a flowchart showing an example of the flow of the crucible measurement method.
  • 6 to 9 are diagrams illustrating examples of actual measurement images.
  • FIG. 10 is a diagram showing the internal residual stress of the silica glass crucible shown in FIG.
  • FIG. 11 is a diagram showing the internal residual stress of the silica glass crucible shown in FIG. 12 and 13 are diagrams illustrating an example of a scattering situation when a crossline laser is used.
  • a crucible measuring device that measures the scattering state of laser light at each position in the thickness direction inside the side wall of a silica glass crucible having a transparent layer and a bubble-containing layer will be described.
  • a crucible measurement method performed using the crucible measurement apparatus will be described.
  • the crucible measuring apparatus in the present embodiment is configured to emit laser light from the inside of the silica glass crucible toward the thickness direction near the upper end of the silica glass crucible.
  • a crucible measuring device measures the scattering condition of the laser beam of each position of the thickness direction inside a silica glass crucible side wall part by imaging a silica glass crucible from the end surface direction.
  • the structure in the thickness direction of the silica glass crucible can be grasped.
  • a light transmission layer a transparent layer that is free from defects such as scratches
  • a light scattering layer a bubble-containing layer or a transparent layer.
  • Even a defect area such as a scratch can be measured.
  • defects such as scratches existing in the transparent layer can be easily found.
  • the thickness of the light transmission layer and the light scattering layer can be measured.
  • a silica glass crucible that reduces the possibility of problems during pulling of the silicon single crystal or a silica glass crucible that is difficult to break is realized. Is possible.
  • the light detector such as eyes, photodiodes, photomultiplier tubes, etc.
  • light cannot be sensed.
  • the laser beam is scattered by reflection or refraction by dust or particles in the air, the laser beam is visually recognized because the light enters the eyes or the like due to the scattering.
  • the intensity is the sum of the secondary wave intensity from each atom, and generally does not become zero. This is the case of light scattering.
  • the atoms constituting the silica glass are dense and the density is uniform, the secondary waves from each atom interfere with each other, and the intensity becomes zero except in a specific direction. Secondary waves that do not disappear as a result of interference become reflected or refracted waves.
  • Light scattering is generally caused by non-uniform substances.
  • laser light is scattered due to the presence of voids, bubbles, defects, etc. in non-uniform silica glass, the light becomes visible. Therefore, the presence of voids, bubbles, defects, layer boundaries, and the like can be known by scattering the laser light.
  • the silica glass crucible to be measured in the present embodiment connects a cylindrical side wall (straight barrel) having an opening at the upper end, a curved bottom, and the side wall and the bottom, and has a curvature that is greater than that of the bottom. And a large corner portion. Moreover, the upper end surface of the side wall part of the silica glass crucible is formed as an annular flat surface.
  • the silica glass crucible in the present embodiment is, for example, a method for producing a silica glass crucible by depositing silica powder in a rotating mold (made of carbon) and arc melting the deposited silica powder layer. It is manufactured by the rotational mold method. Moreover, since the shape near the opening end part of the silica glass crucible tends to be uneven, the opening end part of the silica glass crucible by the rotational molding method is cut with a predetermined width to align the shape of the opening end part.
  • FIG. 1 shows an example of the configuration of the crucible measuring apparatus according to the first embodiment of the present invention.
  • the crucible measuring apparatus photographs a laser light source 2 (light emitting portion) that emits laser light to the silica glass crucible 1 and a scattering state of the incident laser light in the silica glass crucible 1 from the end face direction of the silica glass crucible 1.
  • a camera unit 3 scattering state measuring unit).
  • the laser light source 2 is, for example, a solid laser source or a semiconductor laser source, and is arranged so that laser light is incident in the thickness direction of the silica glass crucible 1.
  • Examples of the laser light source 2 include an AlGaInP (aluminum gallium indium phosphorus) based portable laser light source (output wavelength around 630 nm).
  • a reflecting mirror or an optical fiber for laser transmission can be used for the light irradiation unit.
  • the laser light source 2 in the present embodiment is installed inside the silica glass crucible 1 so as to emit laser light from the inside of the silica glass crucible 1 toward the thickness direction of the silica glass crucible 1.
  • The By installing the laser light source 2 in this manner, laser light is incident on the silica glass crucible 1 from the inside to the outside of the silica glass crucible 1.
  • the laser light source 2 emits laser light in the thickness direction of the silica glass crucible 1
  • the laser light source 2 is not only perpendicular to the normal direction of the side wall of the silica glass crucible 1 but also in an oblique direction. You may install so that light may be radiate
  • the laser light source 2 is preferably installed so that the laser light is incident and transmitted near the end face of the silica glass crucible 1 (for example, near the upper end of the silica glass crucible such as up to a depth of 2 cm from the end face). .
  • the laser light emitted from the laser light source 2 enters the silica glass crucible 1 after passing through the air, for example, and transmits or partially scatters depending on the structure of the silica glass crucible 1. Various scattering situations are shown at each position.
  • silica glass is amorphous, there is basically no crystal grain boundary that causes light scattering.
  • Silica glass appears transparent to the human eye in the visible wavelength range of about 400 to 800 nm. Being transparent in the visible wavelength region of silica glass means that light in this wavelength region is not absorbed or scattered.
  • Light absorption occurs with light having a wavelength of about 400 nm or less due to the energy gap of silica glass, but light with a wavelength exceeding that wavelength is not absorbed, and light oscillation due to plasma oscillation of free electrons in silica glass.
  • scattering occurs with light having a wavelength of about 780 nm or more, light having a wavelength shorter than that wavelength is not scattered.
  • the wavelength range in which the light transmittance of silica glass is relatively high varies depending on the production method, raw materials, and the like, but is about 200 nm to 4000 nm.
  • the laser light emitted by the laser light source 2 (emits 630 nm laser light) is transmitted without being absorbed or scattered (straightly traveling). To do).
  • the laser light is scattered at the boundary between the bubbles and the silica glass. Therefore, when the laser beam emitted from the laser light source 2 enters the bubble-containing layer, a part of the laser beam is scattered. Further, even in a region that is visually determined to be transparent (a transparent layer), if a defect such as a scratch exists in the region, a part of the laser light is scattered by the defect.
  • the laser light source 2 emit a visible light laser (in the range of about 400 to 800 nm).
  • the laser light source 2 used in this embodiment include a red wavelength laser (for example, about 635 nm and about 650 nm), a green wavelength laser (for example, about 532 nm), and a blue wavelength laser (for example, about 410 nm). ) Etc. are used.
  • a laser other than visible light such as a deep ultraviolet laser (for example, 230 to 350 nm) may be used as the laser light source 2.
  • the above-mentioned interaction between silica glass and light in the infrared region is caused by excitation of vibration between ions constituting the glass. Since ions constituting the glass are derived from impurities in the silica glass, the smaller the impurities, the less light is absorbed. Moreover, the light absorption characteristics also change depending on the structure of the silica network depending on the state during glass production. On the other hand, the interaction between silica glass and light in the ultraviolet region is caused by electronic excitation, so that it is different from the interaction with light in the infrared region. Electron excitation depends on the band gap between the valence band and the conduction band of silica glass. By introducing impurities such as alkali metal, the band gap is reduced, and the absorption edge may extend to the visible region.
  • the laser light source 2 having a laser diameter of about 5 to 20 mm measured at a distance of 3 m and an output of about 0.2 mw to 500 mw is used.
  • the exit diameter of the laser light source 2 is, for example, about 0.8 to 5.5 mm.
  • the laser diameter, output, and exit aperture of the laser light source 2 may be other than those exemplified above.
  • the camera unit 3 is a general camera having an imaging element (not shown) such as a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary Metal Oxide Semiconductor) image sensor, a lens unit, and the like.
  • the camera unit 3 in the present embodiment is installed at a position where the end face of the silica glass crucible 1 to be measured can be photographed (that is, in the end face direction), and the laser light incident on the silica glass crucible 1 by the laser light source 2.
  • the scattering state of the light in the thickness direction inside the side wall of the silica glass crucible 1 is configured to be measured from the direction of the annular end face around the upper end opening of the portion where the laser light is incident.
  • the camera unit 3 is installed on the lower side of the silica glass crucible 1 so that the lens unit faces upward. Is done.
  • the laser light incident on the silica glass crucible 1 shows various scattering states according to the structure of the silica glass crucible 1 at each position in the thickness direction of the silica glass crucible 1. Therefore, the camera unit 3 acquires image data indicating the scattering state of laser light at each position in the thickness direction inside the side wall of the silica glass crucible 1 by photographing the end surface of the silica glass crucible 1. Thereafter, the camera unit 3 displays the acquired image data on a display unit (not shown), for example.
  • the observation device such as the camera unit 3 generally has a silica glass crucible 1 at a position where the reflected light or the transmitted light can be observed, that is, in the vicinity of the laser light source 2 that is the light emitting unit. It is installed in the position on the opposite side across the side wall portion.
  • the camera unit 3 is installed at a position in the vertical direction (that is, the end surface direction) as viewed from the incident direction of the laser beam, where the end surface of the silica glass crucible 1 can be photographed.
  • image data indicating the scattering state at each position in the thickness direction of the silica glass crucible 1 can be simply and nondestructively. Can be obtained, and the structure of the layer in the thickness direction can be measured.
  • FIGS. 2 to 4 are schematic diagrams of image data acquired by the camera unit 3 as a scattering state of laser light incident on the silica glass crucible 1.
  • the state of laser light scattering is indicated by two lines, and the intensity of laser light scattering is expressed by the interval between the two lines.
  • the region where the laser light scattering is large is expressed with a wide interval between the two lines, and the region where the laser light scattering is small is expressed with a small interval between the two lines. .
  • the region other than between the two lines indicates that the laser beam is not incident or transmitted, that is, the laser beam is not scattered. If the frequency of scattering increases, the intensity of the scattered light increases. Conversely, if the frequency of scattering decreases, the intensity of the scattered light decreases.
  • FIG. 2 shows that laser light is incident from the inner surface of the silica glass crucible 1, and the incident laser light is transmitted without being scattered in the transparent layer on the inner surface side, but is scattered in the bubble-containing layer.
  • FIG. 3 shows that there is a transparent layer on the inner surface side of the silica glass crucible 1 as in FIG. 2, and there are regions where the intensity of the scattered laser light is different in the bubble-containing layer.
  • the intensity of the scattered laser light is strong in the bubble-containing layer near the transparent layer and near the outside, and the scattering intensity is weak in the region between them. This is because the bubble-containing layer, which is a light scattering layer, is composed of a plurality of layers.
  • FIG. 4 shows that the incident laser light is scattered by the bubble-containing layer and further scattered by the transparent layer region as in FIG. This indicates that there are defects such as scratches that become scattering centers that cannot be visually confirmed in the transparent layer region. By measuring the laser scattered light, defects in the transparent layer that cannot be detected visually are discovered. I can do it.
  • the camera unit 3 shows the state of the laser light incident on the silica glass crucible 1 that shows various scattering states such as transmission or partial scattering according to the layer structure in the thickness direction of the silica glass crucible 1.
  • the image data indicating is acquired.
  • the layer structure in the thickness direction of the silica glass crucible 1 can be easily discriminated without destruction.
  • FIG. 5 is a flowchart showing an example of the flow of the crucible measurement method according to the first embodiment.
  • laser light is emitted from the inside of the silica glass crucible 1 toward the thickness direction of the silica glass crucible 1 using the laser light source 2 (step S101). Thereby, the laser light is incident on the silica glass crucible 1. Thereafter, the laser light incident on the silica glass crucible 1 exhibits various scattering states such as transmission or partial scattering depending on the structure of the silica glass crucible 1.
  • the camera unit 3 measures the scattering condition of the laser beam at each position in the thickness direction of the silica glass crucible 1. That is, image data indicating the scattering state of the laser light is acquired by photographing the end face of the silica glass crucible 1 with the camera unit 3 (step S102). Thereafter, the camera unit 3 displays the acquired image data on the display device, for example.
  • the end surface inside the side wall portion of the silica glass crucible 1 is photographed by the camera unit 3 to obtain image data indicating the scattering state of the laser light at each position in the thickness direction of the silica glass crucible 1 (step S102). . Thereafter, the camera unit 3 displays the acquired image data on the display device, for example.
  • the crucible measuring apparatus in this embodiment analyzes the image data acquired by the camera unit 3, and the structure of the silica glass crucible 1 in the thickness direction such as a light transmission layer or a light scattering layer (light transmission layer, light An image analysis unit (not shown) for determining the thickness of the scattering layer and the light transmission layer can be provided.
  • the crucible measurement method can be configured to analyze the image data and determine the structure of the layer in the thickness direction of the silica glass crucible 1 (light transmission layer, light scattering layer, light transmission layer thickness, etc.).
  • the image analysis unit is a general information processing device including, for example, an arithmetic device and a storage device, and a function of analyzing image data acquired by the camera unit 3 when the arithmetic device executes a program stored in the storage device. Will be realized. That is, the image analysis unit determines the layer structure in the thickness direction of the silica glass crucible 1 based on the image data. This makes it possible to automatically determine the layer structure in the thickness direction of the silica glass crucible 1.
  • the laser beam when the laser beam is incident on the silica glass crucible 1, the laser beam may be incident so that the incident angle becomes a Brewster angle.
  • the laser light source 2 may be configured to emit a p-polarized laser. Note that p-polarized light refers to polarized light whose direction of vibration of the electric field is parallel to the incident surface.
  • the laser light emitted from the laser light source 2 can be incident without being reflected at the interface between the air and the silica glass crucible 1, so that all can be used for observation of the layer structure and the like.
  • the state of the silica glass crucible 1 can be observed.
  • reflection does not occur at the interface between air and the silica glass crucible 1, and therefore, for example, the detection of the structure and defects of layers near the interface is affected by the reflected light. Can be done without.
  • the incident angle does not necessarily have to be exactly the Brewster angle.
  • the Brewster angle By emitting laser light so as to approach the Brewster angle, a certain degree of effect can be obtained even if the angle is not accurate.
  • the silica glass crucible 1 Since the vicinity of the upper end portion of the silica glass crucible 1 where the laser light is incident from the laser light source 2 is a side wall portion having a cylindrical shape, the laser light is incident on the curved surface, and the position of the laser light source 2 is shifted. In some cases, the incident angle changes and the Brewster angle is not reached. Furthermore, as described above, since the silica glass crucible 1 is made by, for example, the rotational molding method, the shape of the manufactured silica glass crucible 1 may be deviated from the design drawing. Therefore, it is necessary to accurately determine the emission position and the incident angle of the laser beam so that the incident angle becomes the Brewster angle at the determined position, and to make the laser beam incident.
  • a 32 inch silica glass crucible has an inner diameter of about 81.3 cm and a mass of 50 kg to 60 kg
  • a 40 inch silica glass crucible has an inner diameter of about 101.6 cm and a mass of 90 kg to 100 kg. Is a large heavy object.
  • the installation position and the installation angle are accurately adjusted by moving the silica glass crucible 1 itself. It is difficult to do.
  • the three-dimensional shape (three-dimensional coordinates) of the inner surface of the silica glass crucible 1 is measured in advance, and the position and angle at which the laser beam is emitted with respect to the measurement position are calculated. Since it can measure for every measurement point, changing the position and angle of a laser light source, the installation position adjustment of the silica glass crucible 1 itself becomes unnecessary.
  • the three-dimensional shape measurement of the inner surface of the silica glass crucible 1 is performed, for example, by providing an internal distance measuring unit such as a laser displacement meter at the tip of the robot arm and contacting the inner distance measuring unit along the inner surface of the crucible. Measure by moving with. Specifically, silica glass is emitted by emitting laser light obliquely with respect to the inner surface of the silica glass crucible 1 at a plurality of measurement points on the movement path of the internal distance measuring unit, and detecting the reflected light. The three-dimensional shape of the inner surface of the crucible 1 can be measured. Then, by utilizing the measurement result, laser light can be easily emitted so that the incident angle becomes the Brewster angle with respect to the silica glass crucible 1.
  • an internal distance measuring unit such as a laser displacement meter
  • the thickness of the light transmission layer and the light scattering layer can be measured.
  • the incident angle is deviated from the normal direction of the incident surface (that is, the laser light is incident on the silica glass crucible 1 in an oblique direction rather than a vertical direction. ) And the error becomes large, and accurate measurement cannot be performed. Therefore, it is desirable that the incident angle ⁇ (angle from the normal direction of the incident surface) of the laser light emitted from the laser light source 2 is emitted so as to satisfy the following formula.
  • the thickness of the silica glass crucible 1 (the thickness of the light transmission layer and the light scattering layer) is represented by T
  • the allowable error is represented by ⁇ T.
  • the relationship among the thickness T, the tolerance ⁇ T, and the incident angle ⁇ of the silica glass crucible 1 is shown in Table 1.
  • Table 1 For example, when the thickness of the crucible is 10 mm, the allowable incident angle of the laser beam when the tolerance is 0.1 mm is within 8.0 °.
  • the thickness of the silica glass crucible 1 is within an allowable error range. (For example, the thickness of the light transmission layer or the light scattering layer) can be measured.
  • the laser diameter B of the laser light (the laser diameter of the portion that is in contact with the silica glass crucible 1) satisfies the following formula. It is desirable to be controlled.
  • an allowable error is represented by ⁇ T
  • a thickness of the silica glass crucible 1 is represented by T
  • a laser diameter is represented by B.
  • the relationship among the thickness T, tolerance ⁇ T, and laser diameter B of the silica glass crucible 1 is shown in Table 2.
  • the allowable laser diameter when the tolerance is 0.1 mm is 1.4 mm.
  • the silica glass crucible 1 is within the allowable error range. Can be measured (for example, the thickness of the light transmission layer or the light scattering layer).
  • the place where the laser beam is incident is not limited to the inside of the silica glass crucible 1.
  • Laser light may be incident from the outside toward the inside in the thickness direction of the silica glass crucible 1. Further, laser light may be incident from the end face direction of the silica glass crucible 1 and the scattering state of the laser light may be measured from the inside of the silica glass crucible 1. In this case, the scattering state is measured while moving the position of the emitted laser light in the thickness direction of the silica glass crucible 1. By doing in this way, it can grasp
  • the laser light source 2 is rotated at a predetermined interval (for example, 2 to 3 degrees, 5 degrees, every 10 degrees, any angle) with laser light emitted from the inside of the silica glass crucible. By doing so, it is possible to make the laser light incident over the entire circumference of the silica glass crucible 1.
  • a predetermined interval for example, 2 to 3 degrees, 5 degrees, every 10 degrees, any angle
  • the thickness distribution and roundness of each layer when there are a plurality of concentric layers at the upper end of the silica glass crucible can be measured.
  • the roundness of the boundary between the transparent layer and the bubble-containing layer can also be measured. Since the roundness of the inner surface of the silica glass crucible 1 can also be measured, the silicon single crystal is pulled by using the roundness of the inner surface of the silica glass crucible 1 and the roundness of the boundary between the transparent layer and the bubble-containing layer. It is possible to calculate whether a transparent layer having a necessary thickness is formed.
  • the heat transfer is not uniform and the temperature distribution of the silicon melt can be uneven. As a result, it becomes difficult to keep the position of the contact interface between the silicon single crystal and the silicon melt constant, and inconveniences such as dislocation may occur.
  • the silica glass crucible 1 By measuring the silica glass crucible 1 using the crucible measuring apparatus and the crucible measuring method of the present embodiment, it is possible to determine the silica glass crucible in which a problem such as the occurrence of dislocation occurs.
  • the laser light source 2 that is a unidirectional laser such as a laser pointer is used as the light emitting unit
  • a light emitting unit other than the unidirectional laser may be used.
  • the laser light source 2 can be configured to emit at a wide angle (for example, the laser beam 2 is emitted with a predetermined angle (eg, 2 to 4 times) larger than the incident angle of the incident laser light. Realized by passing the lens through).
  • a line laser (horizontal laser, vertical laser) or a cross line laser may be used as the light emitting portion.
  • the cross line laser emits laser light in the horizontal direction and the vertical direction by transmitting the emitted laser light through a collimating lens and then through a cylindrical rod lens.
  • a wide range of scattering conditions can be measured at once.
  • a surface laser and a horizontal line laser horizontal laser
  • the layer structure inside the side wall of the silica glass crucible 1 can be measured at once over a wide range.
  • the measurement of the layer structure can be performed without omission over the entire range.
  • a vertical line laser vertical laser: for example, a horizontal laser tilted by 90 degrees
  • a cross line laser it is possible to more clearly determine the layer structure in the bubble-containing layer and the layer structure in the depth direction. It becomes possible to make a judgment.
  • the oblique direction is oblique to the depth direction of the silica glass crucible 1. The depth at which the defect is located can also be determined by emitting the laser at any angle.
  • the laser light source 2 When a cross-line laser or the like is used as the laser light source 2 in the present embodiment, for example, when the line width is about 2 mm within a distance of 5 m and the light is incident on a flat incident object with a distance from the laser light source 2 to the incident object
  • the method for producing a silica glass crucible of the present embodiment includes a silica glass layer forming step and a silica glass crucible inspection step of forming a silica glass layer by cooling after melting the silica powder.
  • the silica glass crucible forming step is performed by (1) rotating a mold having a bowl-shaped inner surface that defines the outer shape of the silica glass crucible, and crystalline or amorphous silica on the inner surface (bottom and side surfaces) of the mold. By depositing the powder to a predetermined thickness, a silica powder layer for the silica glass layer is formed. (2) The silica powder layer is heated to 2000 to 2600 ° C. by arc discharge to melt and solidify to form glass. And (3) cutting the opening end with a predetermined width and aligning the shape of the opening end.
  • the silica glass crucible inspection step includes the step of measuring the scattering state of each position in the thickness direction of the silica glass crucible described above, and is performed on the silica glass crucible that has undergone the silica glass crucible formation step. By selecting a good silica glass crucible in this inspection step, a silica glass crucible having the above-mentioned advantages can be manufactured.
  • FIGS. 6 to 9 are images taken using the camera unit 3 of the scattering state of the laser light when the laser light is actually incident on the silica glass crucible 1 from the inside.
  • FIG. 6 shows a state in which the laser light incident on the silica glass crucible 1 is partially scattered after being transmitted from the inside of the silica glass crucible 1 to a predetermined position.
  • the silica glass crucible 1 includes a light transmission layer (transparent layer having no defects) that is a region through which laser light is transmitted, and light scattering that is located outside the light transmission layer and is a region in which laser light is scattered. It has a layer (such as a bubble-containing layer), and it can be seen that the light scattering layer has a single structure.
  • FIG. 7 shows a state where the incident laser light is strongly scattered once after being transmitted from the inside of the silica glass crucible 1 to a predetermined position, and then the scattering is weakened and then strongly scattered again.
  • the silica glass crucible 1 has a light transmission layer and a light scattering layer outside the light transmission layer, and the light scattering layer is composed of a plurality of layers.
  • FIG. 8 shows that after the incident laser light is transmitted from the inside of the silica glass crucible 1 to a predetermined position, it is strongly scattered once, and once the scattering is interrupted, the laser light is scattered again.
  • the silica glass crucible 1 has a light-transmitting layer and a light-scattering layer outside the light-transmitting layer, and it can be seen that the light-scattering layer is composed of a plurality of layers.
  • FIG. 9 shows that the incident laser light is scattered from the beginning, then once transmitted, and then scattered again.
  • the silica glass crucible 1 has a light transmissive layer and a light scattering layer outside the light transmissive layer, and has a defect in an inner portion of the silica glass crucible 1 that is considered to be in the transparent layer (light It can be seen that a scattering layer is formed).
  • FIGS. 10 and 11 show the strain (internal residual stress) of the silica glass crucible 1 of FIGS.
  • FIG. 10 in the silica glass crucible 1 of FIG. 6 (silica glass crucible having a light transmission layer and a light scattering layer, and it is determined that the light scattering layer has a single structure)
  • the internal residual stress changes gently in the other portions.
  • silica glass has birefringence, if there is an abrupt change in internal residual stress, the refractive index changes abruptly and contrast is seen.
  • the silica glass crucible 1 of FIG. 7 (silica glass crucible having a light transmission layer and a light scattering layer, and it is determined that the light scattering layer includes a plurality of layers). It can also be seen that there is a boundary (rapid change) of internal residual stress even inside the light scattering layer.
  • the strain inspection is generally a destructive inspection and is performed by breaking the silica glass crucible 1. Therefore, the non-destructive and simple measurement of the laser light scattering state according to the present invention is performed instead of the distortion inspection, whereby the distortion inspection can be easily performed. Further, the scattering state of the laser light can be measured, and annealing treatment or the like can be performed according to the result of the measurement (if necessary).
  • the polycrystalline silicon is incorporated into the silica glass crucible 1 in order to produce a silicon single crystal
  • the strain in the silica glass crucible 1 is large, the silica glass crucible 1 may be cracked due to the indentation.
  • the crack may not be generated immediately after the indentation is formed. Accordingly, the single crystal silicon pulling process may break, and in particular, when the silica glass crucible 1 is broken during the melting of the silicon, the pulling apparatus is damaged and the silicon raw material is discarded, which is economical. Loss.
  • the measuring method of the present invention it becomes possible to substitute for the strain measurement of the silica glass crucible 1 by a non-destructive and easy method, and it is possible to prevent the above damage from occurring in advance.
  • FIG. 12 and 13 are diagrams showing a scattering state when a cross-line laser is used.
  • FIG. 12 is a photograph of the scattering state in the thickness direction of the silica glass crucible 1 when laser light is emitted using a cross-line laser. All images photographed by the camera unit 3 are obtained using a cross-line laser. It can be seen that the light transmission layer and the light scattering layer can be discriminated in the range.
  • FIG. 13 shows that the incident crossline laser light is also scattered in the transparent layer region.
  • FIG. 14 shows an example of the configuration of the crucible measuring apparatus according to this embodiment.
  • FIG. 15 is a flowchart illustrating an example of the flow of the crucible measurement method according to the second embodiment.
  • FIG. 16 is a diagram illustrating the influence of the distance between the inner surface of the crucible and the illumination unit on the measurement of the scattering state.
  • a crucible measuring device that measures the scattering state of laser light incident on the silica glass crucible 1 under irradiation with light of a predetermined wavelength will be described.
  • a crucible measurement method performed using the crucible measurement apparatus will be described.
  • the crucible measuring apparatus includes a laser light source 2, a camera unit 3, and an illumination unit 4.
  • the configurations of the laser light source 2 and the camera unit 3 are the same as those described in the first embodiment. Therefore, the overlapping description is omitted.
  • the illumination unit 4 is configured by, for example, an LED (Light emitting diode), and is configured to irradiate light having a wavelength corresponding to the wavelength of the laser light emitted from the laser light source 2. Specifically, for example, when the laser light source 2 emits red laser light, the illumination unit 4 is configured to emit light having a blue wavelength.
  • LED Light emitting diode
  • the light (illumination) emitted by the illumination unit 4 is desirably avoided because illumination with a hue close to that of the laser light makes the laser light scattering inconspicuous. That is, it is desirable that the illumination unit 4 irradiates light that does not include a wavelength near the wavelength of the laser light emitted from the laser light source 2. As an example, when the wavelength of light emitted from the laser light source 2 is 630 nm, it is desirable to use illumination of light having a blue wavelength that does not include a wavelength near 630 nm. When white light is applied to an object and the reflected light looks red, it is because the object reflects light having a wavelength in a region where the human eye looks red and absorbs light of other wavelengths. Therefore, even if the light of only the wavelength of the region that looks blue with human eyes is applied, the object does not look red.
  • the illumination unit 4 emits light adjusted according to the wavelength of the laser light
  • the camera unit 3 is the end surface of the silica glass crucible 1.
  • step S101 laser light is emitted from the inside of the silica glass crucible 1 toward the thickness direction using the laser light source 2 (step S101).
  • the laser light is incident on the silica glass crucible 1.
  • the laser light incident on the silica glass crucible 1 shows various scattering states such as transmission or partial scattering depending on the structure of the silica glass crucible 1.
  • the illumination unit 4 is used to irradiate illumination light corresponding to the laser beam (S201). Thereby, the laser light is incident on the silica glass crucible 1 under illumination by the illumination unit 4.
  • the camera unit 3 measures the scattering state of the laser beam at each position in the thickness direction of the silica glass crucible 1 under illumination by the illumination part 4. That is, image data indicating the scattering state of the laser light is acquired by photographing the end face of the silica glass crucible 1 with the camera unit 3 (step S102). Thereafter, the camera unit 3 displays the acquired image data on the display device, for example.
  • the crucible measurement method in this embodiment measures the scattering state of each position in the thickness direction of the silica glass crucible 1 under irradiation with illumination light. As a result, the structure of the layer in the thickness direction of the silica glass crucible 1 can be grasped based on the measurement result.
  • FIG. 16 shows the relationship of ease of measurement of the scattering state of the laser light depending on the distance between the inner surface (or end face) of the silica glass crucible 1 and the illumination unit 4.
  • FIG. 16A shows a case where the distance between the inner surface of the silica glass crucible 1 and the illumination unit 4 is 100 mm
  • FIG. 16B shows the inner surface of the silica glass crucible 1.
  • the case where the distance with the illumination part 4 is 300 mm is shown.
  • FIG. 16C shows a case where the distance between the inner surface of the silica glass crucible 1 and the illumination unit 4 is 500 mm.
  • the illumination unit 4 is preferably adjusted so that the distance from the inner surface of the silica glass crucible 1 is a predetermined distance (for example, 500 mm).
  • the suitable distance between the silica glass crucible 1 and the illumination part 4 changes according to the intensity
  • the crucible measuring apparatus and measuring method in the present embodiment can employ various other configurations as in the case described in the first embodiment.
  • it is also effective to combine the illumination unit 4 with the above-described line laser or cross line laser (light emitting unit).
  • the illumination unit 4 by emitting red laser light under illumination of blue illumination light by the illumination unit 4, the scattered portion can be measured as purple, and the scattering state can be measured more clearly. Become.
  • the silica glass crucible 1 When manufacturing the silica glass crucible 1 using the rotating mold method, it is more easily desirable through the step of measuring the scattering state of each position in the thickness direction of the silica glass crucible 1 under illumination with the illumination light described above.
  • the silica glass crucible 1 can be manufactured and realized.
  • FIG. 17 is an example of the configuration of the crucible measuring apparatus according to the present embodiment.
  • FIG. 18 is a diagram illustrating an example of a position where the crucible measurement apparatus according to the present embodiment measures a Raman spectrum.
  • FIG. 19 is a flowchart illustrating an example of the flow of the crucible measurement method according to the third embodiment. 20 and 21 are examples of Raman spectra actually measured.
  • a crucible measuring apparatus that measures the scattering state of laser light in the thickness direction of the silica glass crucible 1 by measuring a Raman spectrum (measuring Raman scattering) will be described. Moreover, the crucible measuring method performed using the said apparatus is demonstrated.
  • the crucible measuring apparatus includes, for example, a laser unit 21 (light emitting unit) and a Raman spectroscopic measuring unit 31 (scattering state measuring unit).
  • the Raman spectroscopic measurement unit 31 includes, for example, a Rayleigh light removal filter 311, a spectroscope 312, and a detector 313.
  • the laser unit 21 is, for example, a semiconductor laser or a solid-state laser, and is monochromatic laser light at each position in the thickness direction of the silica glass crucible 1 from the end surface direction of the silica glass crucible 1 toward the end surface of the silica glass crucible 1. (For example, 520 nm green laser light) is emitted. That is, as shown in FIG. 17, the laser unit 21 emits laser light to the end surface of the silica glass crucible 1 while moving the emission position in the thickness direction of the silica glass crucible 1. Thereby, as will be described later, the Raman spectrum at each position in the thickness direction of the silica glass crucible 1 is measured.
  • the Raman spectroscopic measurement unit 31 includes the Rayleigh light removal filter 311, the spectroscope 312, and the detector 313.
  • the Rayleigh light removal filter 311 is a filter for removing Rayleigh scattering that is included in the scattered light and has the same wavelength as the emitted laser light.
  • the laser light emitted from the laser unit 21 enters the end surface of the silica glass crucible 1 and then generates scattered light.
  • This scattered light includes Rayleigh scattered light in addition to Raman scattered light to be measured (Stokes, anti-Stokes, or either). Therefore, the Rayleigh light removal filter 311 is used to remove Rayleigh scattered light.
  • the crucible measuring apparatus in the present embodiment measures the scattering state at each position in the thickness direction of the silica glass crucible 1. Further, the detector 313 is connected to, for example, an information processing device (not shown), and the information processing device can calculate a Raman shift value corresponding to the detected light. Thereby, the Raman spectrum is measured. That is, Raman scattering is measured.
  • the configuration for measuring the Raman spectrum is merely an example. You may comprise so that the Raman spectrum of each position of the thickness direction of the silica glass crucible 1 may be measured using things other than the said structure.
  • the crucible measuring apparatus includes the laser unit 21 and the Raman spectroscopic measuring unit 31.
  • the Raman spectrum of each position in the thickness direction of the silica glass crucible 1 on the end surface of the silica glass crucible 1 is acquired. That is, as shown in FIG. 18, the position of the laser unit 21 is adjusted so as to hit each position in the thickness direction of the silica glass crucible 1, and a Raman spectrum at each position in the thickness direction of the silica glass crucible 1 is acquired.
  • the Raman spectrum at each position in the thickness direction of the end surface of the silica glass crucible 1 similarly includes a plurality of peaks including a peak attributed to a planar four-membered ring and a peak attributed to a planar three-membered ring. have.
  • the measurement is actually performed, there may be a deviation in the Raman shift value of each peak at each position in the thickness direction of the silica glass crucible 1.
  • a plurality of structures may be included in the thickness direction of the silica glass crucible 1, and the plurality of structures are obtained by performing Raman measurement at each position in the thickness direction of the silica glass crucible 1 as described above. Can be measured.
  • the Raman shift is different at each position in the thickness direction of the silica glass crucible 1 when the Raman spectrum is measured, the structure in the thickness direction of the silica glass crucible 1 is different. Deformation is likely to occur when pulling up the silicon single crystal using. Conversely, a Raman spectrum is measured at each position in the thickness direction of the silica glass crucible 1, and the silica glass crucible 1 having the same Raman shift (small difference) at each position in the thickness direction of the silica glass crucible 1 is obtained. By determining, it is possible to determine the silica glass crucible 1 that is not easily broken (not broken).
  • the measurement of the Raman spectrum can also be used as one of methods for discriminating the silica glass crucible 1 that is difficult to break.
  • the Raman shift is the same in the light transmission layer or the light scattering layer (may be in the transparent layer or the bubble-containing layer). It is confirmed whether or not there is, or whether or not the Raman shift in the entire thickness direction is the same.
  • the measurement of the laser light scattering state described in the first and second embodiments and the measurement of the Raman spectrum described in this embodiment are performed simultaneously (or based on the measurement result of the laser light scattering state). It may be configured to perform measurement of a Raman spectrum (Raman scattering). Specifically, for example, the scattering state of laser light emitted from the inside of the silica glass crucible 1 is measured, and laser light is applied to each layer determined to have a different structure based on the measurement of the scattering state of the laser light. A laser beam for Raman excitation is applied under the measurement of the scattering state of the laser beam.
  • the laser beam for scattering measurement is stopped (when illumination light is irradiated by the illumination unit 4, the irradiation of illumination light is also stopped), and Raman measurement is performed.
  • the light transmission layer and the light scattering layer are grasped based on the measurement result of the scattering state of the laser light, and the boundary between the light transmission layer, the light scattering layer, and the light transmission layer and the light scattering layer is determined based on the grasp result. Measure the Raman spectrum in the vicinity.
  • the structure of the layer in the thickness direction of the silica glass crucible 1 can be grasped easily and with higher accuracy.
  • it is desirable to use lasers of different wavelengths for the laser for scattering measurement (laser light emitted from the laser light source 2) and the laser for Raman measurement (laser light emitted by the laser unit 21).
  • the laser unit 21 emits laser light from the end surface direction of the silica glass crucible 1 toward the end surface of the silica glass crucible 1 (S301).
  • the laser light emitted from the laser unit 21 enters the end surface of the silica glass crucible 1 and then generates scattered light. Therefore, after the Rayleigh light is removed, the light is split and the split light is detected for each wavelength. For example, Raman scattering is measured by such a method (S302).
  • the laser light emission point is shifted in the thickness direction of the silica glass crucible 1 (S303).
  • shifting the laser light emission point is shifted in the thickness direction of the silica glass crucible 1 and then Raman scattering is measured again (Yes in S303).
  • Raman scattering measurement is finished (S303, No).
  • the crucible measurement method in the present embodiment performs Raman scattering measurement for each position in the thickness direction of the silica glass crucible 1.
  • the structure of the layer in the thickness direction of the silica glass crucible 1 can be grasped based on the measurement result.
  • the desired silica glass crucible 1 can also be manufactured and implement
  • FIGS. 20 and 21 show the results of actually measuring the Raman spectrum at each position in the thickness direction of the silica glass crucible 1.
  • FIG. 20 shows the result of measuring the Raman spectrum of each position in the thickness direction of the silica glass crucible 1 on the same end face of the silica glass crucible 1 as in FIGS. 6 and 10.
  • FIG. 21 shows the result of measuring the Raman spectrum of each position in the thickness direction of the silica glass crucible 1 on the same end face of the silica glass crucible 1 as in FIGS. 7 and 11.
  • FIGS. 20 and FIG. 21 show the Raman measurement results of the positions of the inner surface side, the boundary between the inner surface and the middle, the middle, the boundary between the middle and the outer surface side, and the outer surface side in order from the bottom.
  • the results of the Raman spectra of FIGS. 20 and 21 are corrected so that the results do not overlap. Therefore, in the following, it is assumed that only the value of the Raman shift is a problem and the intensity is not seen.
  • the silica glass crucible 1 measured in FIG. 20 has a light transmission layer and a light scattering layer, and the light scattering layer is determined to have a single structure. Layer. From the above, it can be considered that the result of Raman measurement and the measurement result of the scattering state in the thickness direction of the silica glass crucible 1 have a certain correlation.
  • the measurement result of the inner surface side and the boundary between the inner surface and the middle indicates the light transmission layer
  • the measurement result of the middle, the boundary between the middle and the outer surface, and the measurement result on the outer surface side indicates the light scattering layer.
  • each boundary (inner surface) of a peak attributed to a plane four-membered ring (peak near 488 cm ⁇ 1 ) and a peak attributed to a plane three-membered ring (peak near 602 cm ⁇ 1 ) are shown. It can be seen that there is a shift in the value of the Raman shift at the boundary between the center and the middle, the boundary between the middle and the outer surface).
  • the silica glass crucible 1 measured in FIG. 21 has a light transmission layer and a light scattering layer, and the light scattering layer is determined to be composed of a plurality of layers. Yes. This also shows that there is a certain correlation between the Raman measurement result and the measurement result of the scattering state in the thickness direction of the silica glass crucible 1.
  • the silica glass crucible 1 described above As shown in Table 3, it can be seen that the respective structures are different on the inner surface side, the intermediate surface, and the outer surface side with the interfaces (interface 1 and interface 2) as boundaries. That is, it can be seen that the silica glass crucible 1 described above has a plurality of layer structures in the thickness direction with each interface as a boundary, and it is understood that the silica glass crucible 1 does not easily crack and does not break.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Metallurgy (AREA)
  • Materials Engineering (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Analytical Chemistry (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • General Health & Medical Sciences (AREA)
  • Biochemistry (AREA)
  • Physics & Mathematics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)

Abstract

L'invention concerne un dispositif de mesure de creuset pour mesurer un creuset en verre de silice, ce dispositif comportant : une unité d'émission de lumière pour émettre un faisceau laser au niveau d'un creuset en verre de silice à mesurer, qui présente une partie corps cylindrique droite comportant une ouverture à son extrémité supérieure, et également une partie plancher formée à l'extrémité inférieure de la partie corps cylindrique droit ; et une unité de mesure d'état de diffusion pour mesurer l'état de diffusion, qui exprime l'état de diffusion du faisceau laser émis par l'unité d'émission de lumière à l'intérieur du creuset en verre de silice. Divers états de diffusion sont exprimés aux emplacements mesurés dans la direction de l'épaisseur du creuset en verre de silice, pour le faisceau laser émis par l'unité d'émission de lumière. Pendant la mesure, l'unité de mesure d'état de diffusion mesure l'état de diffusion de chaque emplacement dans la direction de l'épaisseur du creuset en verre de silice.
PCT/JP2016/001613 2016-03-18 2016-03-18 Dispositif de mesure de creuset, procédé de mesure de creuset et procédé de production de creuset WO2017158655A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
PCT/JP2016/001613 WO2017158655A1 (fr) 2016-03-18 2016-03-18 Dispositif de mesure de creuset, procédé de mesure de creuset et procédé de production de creuset
TW106107890A TW201738528A (zh) 2016-03-18 2017-03-10 坩堝測量裝置、坩堝測量方法以及坩堝的製造方法

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2016/001613 WO2017158655A1 (fr) 2016-03-18 2016-03-18 Dispositif de mesure de creuset, procédé de mesure de creuset et procédé de production de creuset

Publications (1)

Publication Number Publication Date
WO2017158655A1 true WO2017158655A1 (fr) 2017-09-21

Family

ID=59851998

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2016/001613 WO2017158655A1 (fr) 2016-03-18 2016-03-18 Dispositif de mesure de creuset, procédé de mesure de creuset et procédé de production de creuset

Country Status (2)

Country Link
TW (1) TW201738528A (fr)
WO (1) WO2017158655A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2019221191A1 (fr) * 2018-05-17 2019-11-21 株式会社Sumco Procédé et dispositif destinés à mesurer la transmittance d'un creuset de quartz
CN110938871A (zh) * 2019-12-31 2020-03-31 江西中材新材料有限公司 多晶硅铸锭设备及多晶硅铸锭方法
CN110938871B (zh) * 2019-12-31 2024-05-31 江西中材新材料有限公司 多晶硅铸锭设备及多晶硅铸锭方法

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03146496A (ja) * 1989-10-31 1991-06-21 Shinetsu Sekiei Kk シリコン単結晶引上用シリカガラスルツボ
JP2013134177A (ja) * 2011-12-27 2013-07-08 Japan Siper Quarts Corp シリカガラスルツボの三次元形状測定方法
WO2015099001A1 (fr) * 2013-12-28 2015-07-02 株式会社Sumco Creuset en verre de quartz et dispositif de mesure des tensions associé
JP2016064932A (ja) * 2014-09-22 2016-04-28 株式会社Sumco シリカガラスルツボ
JP2016064934A (ja) * 2014-09-22 2016-04-28 株式会社Sumco ルツボ測定方法
JP2016064931A (ja) * 2014-09-22 2016-04-28 株式会社Sumco ルツボ測定装置
JP2016064933A (ja) * 2014-09-22 2016-04-28 株式会社Sumco シリカガラスルツボの製造方法

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03146496A (ja) * 1989-10-31 1991-06-21 Shinetsu Sekiei Kk シリコン単結晶引上用シリカガラスルツボ
JP2013134177A (ja) * 2011-12-27 2013-07-08 Japan Siper Quarts Corp シリカガラスルツボの三次元形状測定方法
WO2015099001A1 (fr) * 2013-12-28 2015-07-02 株式会社Sumco Creuset en verre de quartz et dispositif de mesure des tensions associé
JP2016064932A (ja) * 2014-09-22 2016-04-28 株式会社Sumco シリカガラスルツボ
JP2016064934A (ja) * 2014-09-22 2016-04-28 株式会社Sumco ルツボ測定方法
JP2016064931A (ja) * 2014-09-22 2016-04-28 株式会社Sumco ルツボ測定装置
JP2016064933A (ja) * 2014-09-22 2016-04-28 株式会社Sumco シリカガラスルツボの製造方法

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2019221191A1 (fr) * 2018-05-17 2019-11-21 株式会社Sumco Procédé et dispositif destinés à mesurer la transmittance d'un creuset de quartz
JPWO2019221191A1 (ja) * 2018-05-17 2021-05-20 株式会社Sumco 石英ルツボの透過率測定方法及び装置
JP7196913B2 (ja) 2018-05-17 2022-12-27 株式会社Sumco 石英ルツボの透過率測定方法及び装置
US11703452B2 (en) 2018-05-17 2023-07-18 Sumco Corporation Method and apparatus for measuring transmittance of quartz crucible
CN110938871A (zh) * 2019-12-31 2020-03-31 江西中材新材料有限公司 多晶硅铸锭设备及多晶硅铸锭方法
CN110938871B (zh) * 2019-12-31 2024-05-31 江西中材新材料有限公司 多晶硅铸锭设备及多晶硅铸锭方法

Also Published As

Publication number Publication date
TW201738528A (zh) 2017-11-01

Similar Documents

Publication Publication Date Title
JP5169194B2 (ja) 板ガラス欠陥検出装置、板ガラスの製造方法
US10024784B2 (en) Vitreous silica crucible and evaluation method of the same
KR101638584B1 (ko) 실리카 유리 도가니의 평가 방법, 실리콘 단결정의 제조 방법
US11105754B2 (en) Multi-parameter inspection apparatus for monitoring of manufacturing parts
JP5544836B2 (ja) 表面プラズモン共鳴チップ
CN1902474A (zh) 宝石中缺陷的检测
JP6119926B1 (ja) 金属体の形状検査装置及び金属体の形状検査方法
US11668658B2 (en) Multi-parameter inspection apparatus for monitoring of additive manufacturing parts
JP6405828B2 (ja) ルツボ測定方法
JPH07294422A (ja) 表面近傍結晶欠陥の検出方法およびその装置
JP2016064932A (ja) シリカガラスルツボ
JP2000031229A (ja) 半導体薄膜の検査方法及びそれを用いた半導体薄膜の製造方法
JP6405827B2 (ja) シリカガラスルツボの製造方法
WO2017158655A1 (fr) Dispositif de mesure de creuset, procédé de mesure de creuset et procédé de production de creuset
WO2017158656A1 (fr) Creuset en verre de silice et procédé de production d'un creuset en verre de silice
JP6336867B2 (ja) ルツボ測定装置
JP3746433B2 (ja) ガラス製品の製造方法及び製造装置
JP2000221009A (ja) ガラス材の厚み測定装置及び測定方法
US20170045463A1 (en) Volumetric substrate scanner
JP2000111317A (ja) ガラス材の厚み測定装置及び測定方法
JP6665870B2 (ja) ルツボ管理システム、ルツボ管理方法、シリカガラスルツボの製造方法、シリコンインゴットの製造方法、ホモエピタキシャルウェーハの製造方法

Legal Events

Date Code Title Description
NENP Non-entry into the national phase

Ref country code: DE

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 16894279

Country of ref document: EP

Kind code of ref document: A1

122 Ep: pct application non-entry in european phase

Ref document number: 16894279

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP