WO2000059837A1 - Method for manufacturing quartz glass crucible - Google Patents
Method for manufacturing quartz glass crucible Download PDFInfo
- Publication number
- WO2000059837A1 WO2000059837A1 PCT/JP2000/002010 JP0002010W WO0059837A1 WO 2000059837 A1 WO2000059837 A1 WO 2000059837A1 JP 0002010 W JP0002010 W JP 0002010W WO 0059837 A1 WO0059837 A1 WO 0059837A1
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- WO
- WIPO (PCT)
- Prior art keywords
- gas
- mold
- quartz glass
- quartz
- glass crucible
- Prior art date
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B20/00—Processes specially adapted for the production of quartz or fused silica articles, not otherwise provided for
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B19/00—Other methods of shaping glass
- C03B19/09—Other methods of shaping glass by fusing powdered glass in a shaping mould
- C03B19/095—Other methods of shaping glass by fusing powdered glass in a shaping mould by centrifuging, e.g. arc discharge in rotating mould
-
- 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
- C30B35/00—Apparatus not otherwise provided for, specially adapted for the growth, production or after-treatment of single crystals or of a homogeneous polycrystalline material with defined structure
- C30B35/002—Crucibles or containers
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P40/00—Technologies relating to the processing of minerals
- Y02P40/50—Glass production, e.g. reusing waste heat during processing or shaping
- Y02P40/57—Improving the yield, e-g- reduction of reject rates
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S65/00—Glass manufacturing
- Y10S65/04—Electric heat
Definitions
- the present invention relates to a method for manufacturing a quartz glass crucible, and more particularly to a method for manufacturing a quartz glass crucible that can be used for pulling a semiconductor single crystal and can contribute to an improvement in the yield of the semiconductor single crystal.
- a pulling method is used in which a seed crystal serving as a nucleus is immersed in the melt surface of a molten semiconductor material, and a single crystal is grown from the seed crystal (Chiyoklarsky method: CZ method)
- the quartz glass crucible is used for melting the semiconductor material.
- the melting time increases and the pulling time increases.
- the amount of heat (heat input) provided by the heater it is conceivable to increase the amount of heat (heat input) provided by the heater. Further, it is preferable that the heat input be large in order to maintain a large amount of the semiconductor material melt at a predetermined temperature.
- Japanese Patent Application Laid-Open No. 8-2688727 discloses that silica sand charged in a melting pot is formed into a bowl shape by centrifugal force, heated, and rapidly diffused gas from the outer surface of the bowl-shaped silica sand.
- a method for producing a quartz crucible including a step of removing residual gas contained in voids in silica sand by introducing a quartz crucible is disclosed. Furthermore, in this method of manufacturing a quartz crucible, a vacuum is applied to the bottom of the melting point of the silica sand to remove the residual gas from the voids in the silica sand, thereby generating a flow of the rapid diffusion gas.
- Multi-pulling It may not be possible to cope with the current pulling process in which the heat load is increased due to the increase in diameter of the silicon single crystal and the pulling time is long. Therefore, there is a need for a quartz glass crucible in which bubbles in the inner surface layer are less likely to burst even when the heat load is large or the pulling time is long.
- the rapid diffusion gas replaces the residual gas in the void, so that the growth of bubbles in the quartz glass crucible during high-temperature heating such as in the production of semiconductor single crystals. Prevention can be expected.
- the residual gas such as nitrogen and oxygen is still insufficiently replaced, so that the bubbles in the opaque layer expand during use, the thermal conductivity becomes poor, and the temperature of the quartz glass crucible decreases. Easy to rise. As a result, bubbles in the transparent layer are also easy to burst.
- N 2 and the like confined in the void have a higher density than H 2, which is a rapid diffusion gas. Therefore, H 2 blows through the void due to the difference in density between these gases, and the replacement takes a long time. Therefore, sufficient replacement is not achieved by a short time injection of rapid diffusion gas, and gas such as N 2 remains in the void. This residual gas becomes bubbles in the inner surface layer of the quartz glass crucible, and the number of bubbles cannot be substantially reduced.
- the tendency to increase the heat input further affects the pulling of the semiconductor single crystal.
- the quartz glass crucible When pulled up, the quartz glass crucible is supported on its outer periphery by a graphite holding member heated by a heater, and heat is applied from the heater to the semiconductor material in the quartz glass crucible through the holding member.
- the heaters are generally spaced apart from each other, if the quartz glass crucible is completely transparent, The heat from the heater propagates linearly to the semiconductor material in the quartz glass crucible, and between the heaters, it is difficult to transfer the heat to the semiconductor material. Therefore, in order to transfer heat evenly, the outer periphery of the quartz glass crucible should be so distributed that the heat rays emitted from the heater diffuse in multiple directions when passing through the quartz glass crucible and their distribution is equalized. An opaque layer containing bubbles is formed in the vicinity.
- the temperature of the quartz glass crucible also rises extremely, devitrification will occur around 1550 ° C. Furthermore, if the heat of the heater is not sufficiently transferred to the semiconductor material melt in the quartz glass crucible, the temperature of the semiconductor material melt may partially decrease, causing icing (partial solidification).
- the large heat input effectively acts on the semiconductor material in the quartz glass crucible to contribute to pulling up in a short time, and the heat released from the heater is reflected on the heater side, causing abnormal temperature rise and icing. Therefore, there has been a demand for a quartz glass crucible capable of uniformly transmitting heat from a heater to the semiconductor material contained therein and its melt.
- FIG. 2 is a diagram showing the results of an investigation of the relationship between the average bubble diameter and the single crystal yield in a layer of about 1 mm in the inner surface of the corner portion of the quartz glass crucible, that is, the boundary portion between the bottom and the side wall.
- the reason for paying attention to the corners is that a large load is particularly applied to the corners when pulling the single crystal, and the bubbles existing in the corners are closely related to the yield of the single crystal.
- the sample of the quartz glass crucible used for the survey was 22 inches in diameter.
- the yield is about 100 kg by heating and melting 100 kg of silicon polycrystal.
- the present invention reduces the number, size, and expansion ratio of bubbles in the transparent layer to prevent the bursting of bubbles, thereby improving the yield of the semiconductor single crystal, and appropriately controls the number, size, and expansion ratio of bubbles in the opaque layer. Accordingly, it is an object of the present invention to provide a method of manufacturing a quartz glass crucible capable of suppressing a rise in temperature of the quartz glass crucible and increasing the thermal efficiency when pulling a semiconductor single crystal.
- the present invention provides a method for producing a quartz glass crucible in which arc discharge is performed between graphite electrodes arranged in a rotating mold to melt quartz powder and form a crucible, wherein H 2, 02, H 2 ⁇ , He, Ne gas
- the first characteristic is that the method comprises the steps of supplying at least one of the above, and supplying quartz powder to the inner surface of the mold by passing the supplied gas through an atmosphere.
- the second feature is that H 2 gas and 02 gas are supplied in the gas supply stage.
- the present invention has a third feature in that the quartz powder is dispersed in the mold so that the quartz powder is softened in an atmosphere of arc discharge before reaching the inner surface of the mold. .
- the present invention provides the above-mentioned gas and quartz powder are supplied through a double cylinder.
- the quartz powder is supplied from an inner cylinder and the gas is supplied from an outer cylinder.
- the fourth and fifth features are that the H 2 gas is supplied from the inner cylinder and the H 2 gas is supplied from the outer cylinder, respectively.
- the sixth point is that the tip of the double cylinder is retracted from the tip of the outer cylinder.
- the present invention has a seventh feature in that at least the quartz powder of the quartz powder and the gas is intermittently supplied while the arc discharge is maintained.
- impurities such as alkaline earth metals and heavy metals contained in the supplied quartz powder are replaced with a gas such as H 2 or burned in a high-temperature atmosphere, thereby increasing the purity of the quartz powder.
- the supplied ⁇ 2 gas and H 2 gas allow the inside of the mold to reach a high-temperature atmosphere in which the quartz powder can be melted in a short time, facilitating degassing and reducing the air in the product crucible.
- the degree of mixing of bubbles can be suppressed.
- the graphite constituting the electrode is easily oxidized by high temperature, mixing of the graphite into the product crucible is suppressed.
- the supplied gas diffuses into the product crucible, and has the effect of reducing the pressure inside the bubbles.
- the quartz powder is deposited on the fused surface of the previously formed quartz glass in a softened state, the quartz powder is easily compatible with the fused surface, and thus adheres to the quartz surface. Impurities are easily removed Les ,.
- the directivity can be controlled by the direction of the double cylinder.
- the quartz powder is Is surrounded by gas at the tip of the double cylinder, and has good contact with the gas.
- the temperature of the fused layer of quartz is prevented from lowering, and the fused layer continuously reacts with the atmospheric gas to further promote the removal of impurities that cause bubbles.
- the present invention has the following features regarding the formation of the opaque layer.
- a step of forming a deposited layer of quartz powder along an inner surface of the mold starting an arc discharge after supplying He and Z or H 2 gas (hereinafter, representatively referred to as He gas) to the deposition layer from a predetermined position between a side wall and a bottom portion of the deposition layer; Stopping the supply of the He gas and exhausting from the deposition layer when a thin film melt layer is formed on the surface of the layer; and when the deposition layer reaches a predetermined degree of vacuum,
- He gas He and Z or H 2 gas
- the present invention may further comprise, after the deposition layer is formed, covering the upper opening of the mold and evacuating the inside of the mold. And starting the arc discharge by opening the lid when the pressure in the mold rises to a predetermined value.After the lid is opened, the supply of the He gas is performed.
- the ninth feature is that the scheduled time is maintained. According to the ninth feature, a higher degree of vacuum can be obtained because the mold is sealed with the lid. Therefore, the He gas supplied thereafter can sufficiently penetrate into the voids in the sedimentary layer. Replacement with He gas is sufficiently performed.
- the present invention provides a step of starting an arc discharge after supplying He gas to the pile from a predetermined position between a side wall and a bottom of a mold, and a step of forming a thin film melted layer on the surface of the deposited layer.
- the present invention switches the supply position of the He gas to the upper part of the side wall of the mold when the thin film molten layer is formed on the surface of the deposition layer, and supplies the He gas before the arc discharge.
- the first characteristic is that the deposition layer is exhausted from the position where the gas was discharged, and this characteristic causes the He gas to flow from the upper part to the lower part in the deposition layer, and the replacement action is performed on the entire deposition layer. Can be reached.
- the present invention also includes a step of covering the upper opening of the mold with the deposition layer and evacuating the inside of the mold; and, when the inside of the mold reaches a predetermined degree of vacuum, between the side wall and the bottom of the mold. Supplying the He gas into the mold from the predetermined position, and opening the lid to start the arc discharge when the pressure in the mold rises to a predetermined value.
- a feature of the present invention is that the step of exhausting the deposited layer from the upper part of the side wall of the mold while continuing to supply the He gas when the thin film molten layer is formed has a 12th feature.
- the present invention also provides a step of, after the deposition layer is formed, covering the upper opening of the mold and evacuating the inside of the mold, and when the inside of the mold reaches a predetermined degree of vacuum, Supplying He gas into the mold from a predetermined position between the side wall and the bottom of the mold, and adjusting the pressure in the mold to a predetermined value.
- the step includes switching and exhausting the deposited layer from the position where the He gas was supplied before the arc discharge.
- the present invention having the 12th and 13th features operates similarly to the invention having the 10th and 11th features.
- the quartz glass crucible as a product is heated to a high temperature (145 to Even when the temperature reaches 700 ° C.), the expansion of bubbles mixed into the outer surface layer of the quartz glass crucible can be suppressed. As a result, the thermal conductivity of the quartz glass crucible is not impaired, and the abnormal temperature rise of the quartz glass crucible is suppressed.
- the present invention provides a method for producing a gas containing H 2, O 2, H 20, He, and Ne in the mold after melting the deposition layer for a predetermined time, that is, after forming the opaque layer.
- the fifteenth feature is that the quartz powder is sprayed into the mold so that it is softened in an arc atmosphere before the quartz powder as the material powder reaches the inner surface of the mold.
- the present invention having the 14th and 15th features operates in the same manner as the inventions according to the 9th to 13th features, and also acts in the same manner as the inventions having the 1st and 2nd features.
- FIG. 1 is a sectional view showing a main part of a quartz glass crucible manufacturing apparatus according to an embodiment of the present invention.
- FIG. 2 is a diagram showing the relationship between the bubble diameter and the yield of a single crystal.
- Figure 3 is a diagram comparing air bubbles before and after using a quartz glass crucible.
- FIG. 4 is a diagram showing the relationship between the coefficient of expansion and the yield of single crystallization.
- FIG. 5 is a cross-sectional view of a main part showing a quartz glass crucible manufacturing apparatus according to the second embodiment.
- FIG. 6 is a cross-sectional view of a main part showing an apparatus for manufacturing a quartz glass crucible according to the third embodiment.
- Figure 7 shows a comparison of bubbles before and after using the opaque layer of a quartz glass crucible.
- FIG. 8 is a cross-sectional view of a relevant part showing a device for manufacturing a quartz glass crucible according to the fourth embodiment.
- FIG. 9 is a cross-sectional view of a principal part showing an apparatus for manufacturing a quartz glass crucible according to the fifth embodiment.
- FIG. 10 is a diagram comparing bubbles before and after using the opaque layer of the quartz glass crucible according to the fourth and fifth embodiments.
- the present embodiment provides a means for reducing the number and size of bubbles existing in the transparent layer formed on the inner surface of the quartz glass crucible and for reducing the expansion rate of the bubbles.
- alkaline earth metal such as N 2 gas
- a quartz glass crucible with few bubbles can be obtained by introducing one or more kinds of gases such as H2, 02, H2 ⁇ , He, and Ne in a mixed state. If the above gas is introduced during arc discharge, the inside of the mold will be extremely high Because it becomes warm. In the conventional Arc Bernouli method without introducing gas, as the temperature in the mold increases, the surface of the raw material first sinters at around 650 ° C, and then reaches around 175 ° C. Then it starts melting.
- gases such as H2, 02, H2 ⁇ , He, and Ne
- degassing is facilitated by shortening the time required for the sintering step to reach a molten state in a short time, and it is possible to reduce bubbles to be mixed.
- the inside of the mold easily reaches a high temperature, and the degree of sintering of the raw material can be reduced in the high temperature atmosphere.
- the expansion rate of the bubbles is reduced by reducing the pressure inside the bubbles.
- the expansion rate of bubbles can be reduced by introducing H 2 gas or 02 gas during arc discharge.
- the introduced gas diffuses into the quartz glass crucible and bubbles in the quartz glass crucible and easily dissolves in the quartz glass.
- H 2, He, and Ne are particularly easy to diffuse and easily dissolve in quartz glass.
- the atoms of these small gas radius atoms can freely move through the silica matrix in the quartz glass. As a result, it is easily released to the outside of the quartz glass under reduced pressure and high temperature conditions, lowering the internal pressure of the bubbles and suppressing the expansion of the bubbles.
- the number of bubbles and the expansion rate of the bubbles are reduced by eliminating the graphite from the graphite electrodes.
- Quartz glass crucibles are manufactured by melting and solidifying raw materials in a mold. The heat of fusion is obtained from the arc discharge by the graphite electrode. Daraite generated from the graphite electrode is bonded to 02 in the mold, and most of it burns, but some remains in the manufactured quartz glass crucible to form bubbles and increase its expansion rate. I do. In other words, the remaining graphite reacts with O 2 trapped in bubbles under low pressure and high temperature conditions, that is, under pulling conditions, to generate CO gas and expand the bubbles.
- gases such as H 2, 02, H 2 ⁇ , He, and Ne are introduced during arc discharge in order to prevent graphite from being mixed into the inner surface of the quartz glass crucible.
- gases such as H 2, 02, H 2 ⁇ , He, and Ne are introduced during arc discharge in order to prevent graphite from being mixed into the inner surface of the quartz glass crucible.
- graphite is linked to 02 and burns, but the introduction of other gases causes the inside of the mold to become extremely hot, making it more combustible with 02 in the air.
- H2, 02 and H2O promote the oxidation of graphite.
- FIG. 1 is a cross-sectional view of a main part showing a device for manufacturing a quartz glass crucible.
- a mold 1 made of metal preferably stainless steel
- the mold 1 has an inner diameter of 57 O mm, and the mold 1 is rotated about the shaft 2 by a rotating device (not shown).
- a pair of graphite electrode electrodes 4 and 5 are held on a heat shield plate 3 disposed at the upper center of the mold 1.
- a double cylinder is formed by the gas nozzle 6 and the introduction pipe 7 for introducing the raw material quartz powder, and the double cylinder is arranged adjacent to the graphite electrode 4.
- the double tube has a quartz powder inlet tube 7 inside and a gas nozzle 6 outside, but the reverse is also possible.
- quartz powder is used as the raw material powder.
- quartz powder used here is not limited to quartz but includes quartz glass, such as quartz, silica sand, etc., including silicon dioxide (silicone force). Also includes powders of materials known as raw materials for crucibles.
- a gas introduction pipe 9 can be additionally provided between the graphite electrode electrodes 4 and 5.
- a crucible manufacturing process using the manufacturing apparatus configured as described above will be described.
- the mold 1 is rotated, and quartz powder (for example, a particle size of 60 # to 150 #) is injected into the inner peripheral surface of the mold 1 through the introduction pipe 7. Since mold 1 is rotating, the introduced quartz powder sticks to the periphery of mold 1 by centrifugal force and accumulates.
- the introduction of the quartz powder at this time may be performed using the introduction pipe 7 or may be performed by another device.
- a voltage is applied between the graphite electrodes 4 and 5 to cause arc discharge. This arc heat causes the quartz powder adhered to the mold 1 to melt, forming an opaque layer L 1 (see FIG. 1) that constitutes the outer peripheral surface of the quartz glass crucible.
- a transparent layer L2 (see FIG. 1) is formed.
- quartz powder and H 2 gas are supplied to the mold 1 through the introduction pipe 7 and the gas nozzle 6.
- the supply amount of the quartz powder is preferably, for example, 80 to 160 g / min
- the supply amount of the H 2 gas is preferably, for example, 60 to 100 liters Z.
- the atmosphere near the arc of the graphite electrodes 4 and 5 is 2000 ° C or more (500 ° C or more during the arc), and the quartz powder sprayed in this atmosphere softens. .
- the softened quartz powder migrates directly onto the opaque layer L1, or after falling to the bottom of the mold, rises by centrifugal force and deposits on the opaque layer L1, forming a transparent layer L2. I do.
- the temperature of the fused quartz surface layer is preferably maintained at a high temperature (preferably 200 ° C. or more). This is because the higher the temperature, the more residual gas is released from the molten surface layer into the atmosphere.
- the continuous application of quartz powder may cause a decrease in the temperature of the molten surface layer, so it is recommended that the quartz powder be applied intermittently. For example, after spraying quartz powder and supplying H 2 gas for 10 minutes, temporarily stop spraying quartz powder and continue melting operation for another 20 minutes. This operation is repeated to finish the transparent layer L2 to a desired thickness.
- FIG. 3 is a diagram showing the results of investigation on the number and size of bubbles before and after use in a quartz glass crucible manufactured by the manufacturing method according to the present embodiment. Observation of air bubbles before use was performed on 20 samples at a depth of 0.5 mm to 1.5 mm from the inner surface by setting a 20 ⁇ microscope at the inner corner of the quartz glass crucible. did.
- the maximum size (diameter) of bubbles before use is 51 ⁇ m
- the minimum is 3 m
- the average is 13 ⁇ m
- the maximum size of bubbles after use is 90 urn
- the minimum was 9 / m and the average was 34 m.
- the number of bubbles in the quartz glass crucible was 0.14 / mm3 before use, and 0.27 / mm3 after use.
- the average bubble size after use was 34 m, and the single crystal yield was 100% consistent with the results described with reference to FIG.
- FIG. 4 is a diagram showing the relationship between the coefficient of expansion and the yield of single crystallization.
- the use conditions and observation conditions of the quartz glass crucible for investigating the yield of single crystallization are the same as in the example of FIG.
- the expansion rates of the bubbles in the 13 types of crucibles are distributed in the range of 1.5 to 3.5.
- the single crystallization yield was favorable (100%) for samples having an expansion coefficient of less than “2.5”.
- FIG. 5 is a cross-sectional view of a principal part showing an apparatus for manufacturing a quartz glass crucible according to the second embodiment, and the same reference numerals as in FIG. 1 denote the same or equivalent parts.
- the inner inlet pipe 70A is configured so that the raw material powder can be supplied through the hopper 8, and the ⁇ 2 gas can be introduced along the way. It has a branch or inlet 70B.
- the outer tube of the double cylinder 70 that is, the gas nozzle 6, has an inlet 6A for introducing the H 2 gas as in the first embodiment.
- the introduction direction of the quartz powder can be arbitrarily directed according to the direction of the introduction pipe 7OA.
- the present invention is not limited to this, and quartz powder and ⁇ 2 gas may be charged into mold 1 using separate nozzles.
- the opaque layer L1 is formed in the same manner as in the first embodiment.
- a transparent layer L2 (see FIG. 1) is formed.
- quartz powder, O 2 gas and H 2 gas were supplied to the mold 1 through the double cylinder 70.
- the supply amount of the quartz powder is, for example, 80 to 160 gZ
- the total supply amount of the 02 gas and the H 2 gas is, for example, 60 liter to 100 liters. It's better to use it for littorno.
- the ratio of the supply amounts of O 2 gas and H 2 gas is preferably 1: 6. 02 Too much gas is more likely to cause bubbles, so increase H 2 gas to the maximum In this case, the ratio can be set to 1:10.
- quartz powder sprayed in the atmosphere near the arc of the graphite electrodes 4 and 5 softens and moves directly onto the opaque layer L1, or once falls to the mold bottom and then rises by centrifugal force. Then, the transparent layer L2 is formed by depositing on the opaque layer L1.
- quartz powder that has passed through an atmosphere at a high temperature after the 02 gas and the H 2 gas have been introduced softens very easily.
- the transparent layer L2 made of quartz powder that has been softened by being injected into the vicinity of the arc together with the 02 gas and H2 gas has little residual gas as a source of bubbles. Also, the gas remaining in the slightly transparent layer L2 ⁇ is easily released to the outside of the quartz glass under reduced pressure and high temperature conditions in a H2-rich environment, as in the case where only H2 gas is introduced. You.
- the quartz glass crucible can be maintained at an H2 rich. .
- the water vapor generated during the pulling is discharged from the top of the quartz glass crucible by the high-temperature convection of the arc discharge without contacting the inner surface of the quartz glass crucible.
- the O 2 gas is supplied from the inner cylinder of the double cylinder together with the raw material powder, and the H 2 gas is supplied from the outer cylinder.
- the H 2 gas is supplied together with the raw material powder.
- And 02 gas may be supplied from the outer cylinder.
- He gas is supplied from the pot that melts the quartz powder, that is, the mold, and the gas in the quartz powder voids deposited on the inner wall of the mold is filled with He gas. It was made to be replaced. The details will be described below with reference to the drawings.
- FIG. 6 is a cross-sectional view of a main part of a manufacturing apparatus used in the method for manufacturing a quartz glass crucible according to the third embodiment, and the same reference numerals as in FIG. 1 indicate the same or equivalent parts.
- An end of the cooling water pipe 1B fixed to the inner wall 1A of the hollow portion of the mold 1 is drawn out below the mold 1 and connected to a circulation device (not shown).
- a hole 10 for passing He as a replacement gas is formed at the bottom of the inner wall 1A of the mold 1.
- the hole 10 for supplying He can be provided not only at the bottom but also at any position between the bottom and the side wall of the mold 1 (see FIG. 9 described later).
- the hollow space between the double walls of the mold 1 is filled with He gas supplied from the bottom of the mold 1, and the filled He gas penetrates the inner wall 1 A upward through the hole 3.
- an exhaust hole 11 is formed in the inner wall near the upper end of the mold 1, that is, near the upper opening of the mold, and the hole 11 is connected to the joint 12. Is connected to a tube 13 extending below the mold 1 and communicating with a vacuum pump (not shown). The tube 13 may extend downward through a hollow portion in the mold 1.
- the inner diameter of the mold 1 is, for example, 57 O mm, and the mold 1 is rotated by a rotating device (not shown) as shown by an arrow 14. Prior to the generation of an arc between the electrodes 4 and 5, a deposited layer 15 of the raw material powder is formed along the wall surface inside the mold 1. H 2 gas at inlet 6 A of gas nozzle 6 It is the same as the manufacturing apparatus in FIG. 1 that the upper end of the introduction pipe 7 is connected to a raw material hobber containing quartz powder.
- a procedure for manufacturing a quartz glass crucible using the manufacturing apparatus having the above configuration will be described.
- a deposited layer 15 of quartz powder is formed.
- the particle size and supply amount of the quartz powder are the same as in the first embodiment.
- an arc is discharged between the graphite electrodes 4 and 5 to start melting the deposited layer 15.
- the supply of He gas to the deposition layer 15 through the hole 10 of the mold 1 is started.
- the supply rate of He gas is preferably about 30 liters / minute.
- arc discharge is performed.
- One to two minutes after the start of the arc discharge a thin molten layer is formed on the surface of the deposited layer 15.
- the supply of the He gas is stopped when the thin film melt layer is formed, and the unmelted portion of the deposition layer 15 is exhausted through the hole 11.
- a predetermined degree of vacuum for example, 30 torr
- He is introduced again. It should be noted that a small amount of He gas (less than 10 liters / minute) may be continuously supplied during the evacuation without stopping the supply of He gas when the thin film molten layer is formed. '
- the He gas is introduced when the degree of vacuum is increased, so that the He gas is effectively absorbed by the unmelted deposited layer 15 and the void (space) of the deposited layer 15 is formed.
- the air inside is sufficiently replaced by He gas.
- N2 gas and O2 gas in the opaque layer formed by melting the sedimentary layer 15 are extremely small.
- the expansion coefficient becomes small.
- the supply of He gas resumed after exhaust may be stopped after a preset time, or a small amount (1
- a transparent layer is formed on the opaque layer, that is, on the inner surface side of the quartz glass crucible.
- the transparent layer is formed in the same manner as in the first embodiment, while supplying H 2 gas from the gas nozzle 6 and simultaneously sprinkling quartz powder into the mold 1 through the introduction pipe 7.
- Figure 7 is a diagram showing the results of a survey on the number of bubbles, the bubble diameter, and the expansion rate in the opaque layer. The observation of the bubbles before and after use was performed in the same manner as in the case of the transparent layer. It is.
- the unit of the number is unit / mm 3
- the unit of the bubble diameter is m.
- the number of bubbles and the diameter of bubbles before use are almost the same between the conventional product and the improved product by the manufacturing method of the third embodiment.
- FIG. 8 and 9 are cross-sectional views of an apparatus used in the manufacturing method according to the modification, showing only the main part of the mold 1, and omitting the electrodes 4, 5 and the cooling water pipe 1B.
- the same reference numerals as those in FIG. 6 indicate the same or equivalent parts.
- a bottom hole 10 is provided at the bottom of the inner wall 1A of the mold 1, and a side hole 16 is provided at the side.
- a vacuum pump 18 and a He gas supply source 19 are connected to the bottom of the mold 1 via a switch 17.
- the mold 1 is covered with a lid 20 before the start of arc discharge by the electrodes 4 and 5.
- the lid 20 is put on the upper opening of the mold 1, and the vacuum pump 18 is operated to form the mold 1 through the bottom hole 10 and the side hole 16. Exhaust the inside.
- the switch 17 is switched to He.
- the gas supply source 19 side Switch to the gas supply source 19 side, and supply He gas into the mold 1 from the bottom hole 10 and the side hole 16.
- the lid 20 is opened to shift to the stage of starting arc discharge. Even after the lid 20 is opened to start the arc discharge, the supply of the He gas is continued. It is preferable to supply at least until a thin film fusion layer is formed on the surface of the deposition layer 15.
- a bottom hole 10 is provided at the bottom of the inner wall 1A of the mold 1, and a side portion is provided separately from the hole 16 at an upper portion thereof.
- a top hole 11 is provided, and a side hole 16 communicates with the bottom hole 10.
- He gas is supplied to the deposition layer 15 through the side hole 16 and the bottom hole 10, and He gas is supplied. After supplying for a predetermined time (for example, 5 minutes), the operation shifts to arc discharge.
- the deposition layer 15 When a thin film melted layer is formed on the surface of the deposition layer 15 by arc discharge, the deposition layer 15 is exhausted from the upper hole 11 on the side wall of the mold 1 while the supply of He gas is continued. The supply and exhaust of the He gas cause a flow of the He gas from the bottom to the top in the sedimentary layer 15, and the voids in the stack 15 are replaced by the He gas.
- the flow of the He gas may be generated from the upper side of the deposition layer 15 to the lower side.
- a predetermined time for example, 5 minutes
- arc discharge is performed.
- the supply position of He gas is switched to the upper hole 11 on the side wall of the mold 1, and He gas is discharged before arc discharge.
- the deposition layer 15 is evacuated from the position where the gas was supplied, that is, from the bottom hole 10 and the side hole 16 of the mold 1. This causes a downward flow of He gas.
- a He gas supply source 19 is connected via a switch 23 to two tubes 21 and 22 drawn from the bottom of the mold 1.
- the mold 20 When the flow of He gas is generated in the deposition layer 15 using the apparatus of FIG. 9, similarly to the modification shown in FIG. 8, the mold 20 is covered with the lid 20 to form a closed space. Prior to arc generation, the inside may be evacuated, and He gas may be introduced into the interior to replace the atmosphere with He gas.
- a film containing water exists around the quartz powder, it is preferable to remove this water in advance. Moisture can be removed by heating the deposited layer 15 prior to arc generation.
- a halogen lamp should be installed in Mold 1 so as to face the deposition layer 15, the atmosphere in Mold 1 should be raised to about 100 ° C, and the deposition layer 15 should be Can be heated. By removing the water around the quartz powder in advance, the replacement with He gas can be performed in a short time. Further, a heater may be incorporated in the lid 3 or the lid 20 to heat the deposited layer 15.
- FIG. 10 is a diagram showing the results of investigation on the number of bubbles, the bubble diameter, and the expansion coefficient in the opaque layer of the quartz glass crucible manufactured by the manufacturing methods of the fourth and fifth embodiments.
- the improved product 2 is the one according to the fourth embodiment, in which an arc is generated by introducing He gas after covering the lid 20 and evacuating to 5 Torr.
- the improved product 3 is according to the fifth embodiment, in which a He gas flow is generated in the deposition layer 15 at a vacuum of 160 torr.
- the improved product 3 has a higher expansion coefficient than the improved product.
- the expansion coefficient can be reduced by heating the deposition layer 15 with the halogen lamp or the like.
- the coefficient of expansion is also increased by heating the deposition layer 15 in advance. Of course, it can be further reduced.
- the force described with reference to the case where H2 is used as the introduced gas is the same as the above, and the introduced gas other than H2 gas (at least one of 02, H2 1, He, and Ne) is used.
- the introduced gas other than H2 gas at least one of 02, H2 1, He, and Ne
- the number of bubbles, the diameter of bubbles, and the like were improved, and good results were obtained for the single crystal yield.
- gas supplied from the mold 1 in the third to fifth embodiments is not limited to He gas, and other rapid diffusion gas, for example, H 2 may be used. 2 may be mixed. Industrial applicability
- quartz powder as a raw material Since the voids in the deposited layer are replaced with He gas, the bubbles mixed into the opaque layer of the quartz glass crucible have a low coefficient of expansion, and the thermal conductivity should be moderate when used at high temperatures. Can be. As a result, abnormal heating of the quartz glass crucible can be avoided, and expansion and burst of bubbles in the transparent layer can be prevented.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Crystallography & Structural Chemistry (AREA)
- Metallurgy (AREA)
- Manufacturing & Machinery (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
- Glass Melting And Manufacturing (AREA)
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP20000912964 EP1094039B1 (en) | 1999-04-06 | 2000-03-30 | Method for manufacturing quartz glass crucible |
US09/701,427 US6553787B1 (en) | 1999-04-06 | 2000-03-30 | Method for manufacturing quartz glass crucible |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP11/98458 | 1999-04-06 | ||
JP9845899 | 1999-04-06 | ||
JP11/359937 | 1999-12-17 | ||
JP35993799 | 1999-12-17 |
Publications (1)
Publication Number | Publication Date |
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WO2000059837A1 true WO2000059837A1 (en) | 2000-10-12 |
Family
ID=26439627
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2000/002010 WO2000059837A1 (en) | 1999-04-06 | 2000-03-30 | Method for manufacturing quartz glass crucible |
Country Status (5)
Country | Link |
---|---|
US (1) | US6553787B1 (ja) |
EP (1) | EP1094039B1 (ja) |
KR (1) | KR100383796B1 (ja) |
TW (1) | TWI230696B (ja) |
WO (1) | WO2000059837A1 (ja) |
Cited By (3)
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JP2003034593A (ja) * | 2001-07-23 | 2003-02-07 | Shinetsu Quartz Prod Co Ltd | シリコン単結晶引上げ用石英ガラスるつぼの製造方法及び装置 |
US6886364B2 (en) * | 2000-05-31 | 2005-05-03 | Heraeus Quarzglas Gmbh & Co. Kg | Method for producing quartz glass crucible |
JP2005206446A (ja) * | 2004-07-16 | 2005-08-04 | Shinetsu Quartz Prod Co Ltd | シリコン単結晶引上げ用石英ガラスるつぼおよびその製造方法 |
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JP4300334B2 (ja) * | 2002-08-15 | 2009-07-22 | ジャパンスーパークォーツ株式会社 | 石英ガラスルツボの再生方法 |
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KR101312999B1 (ko) * | 2007-07-28 | 2013-10-01 | 쟈판 스파 쿼츠 가부시키가이샤 | 석영 유리 도가니 제조 방법 및 제조 장치 |
JP4671999B2 (ja) * | 2007-11-30 | 2011-04-20 | ジャパンスーパークォーツ株式会社 | 石英ガラスルツボの試験方法 |
KR100976239B1 (ko) * | 2008-01-10 | 2010-08-17 | 주식회사 원익 쿼츠 | 다층 석영 유리의 제조방법 및 제조장치 |
DE102008026890B3 (de) | 2008-06-05 | 2009-06-04 | Heraeus Quarzglas Gmbh & Co. Kg | Verfahren und Vorrichtung zur Herstellung eines Tiegels aus Quarzglas |
US20100000465A1 (en) * | 2008-07-07 | 2010-01-07 | Japan Super Quartz Corporation | Method for producing vitreous silica crucible |
TWI410534B (zh) * | 2008-07-10 | 2013-10-01 | Japan Super Quartz Corp | 石英玻璃坩堝及使用其之矽單晶拉提方法 |
JP5344423B2 (ja) * | 2008-09-26 | 2013-11-20 | 株式会社Sumco | 炭素電極の製造方法および石英ガラスルツボの製造方法 |
DE102008061871B4 (de) * | 2008-12-15 | 2012-10-31 | Heraeus Quarzglas Gmbh & Co. Kg | Schmelztiegel für den Einsatz in einem Tiegelziehverfahren für Quarzglas |
US8272234B2 (en) | 2008-12-19 | 2012-09-25 | Heraeus Shin-Etsu America, Inc. | Silica crucible with pure and bubble free inner crucible layer and method of making the same |
US8240169B2 (en) * | 2009-01-08 | 2012-08-14 | Japan Super Quartz Corporation | Vitreous silica crucible manufacturing apparatus |
JP4987029B2 (ja) * | 2009-04-02 | 2012-07-25 | ジャパンスーパークォーツ株式会社 | シリコン単結晶引き上げ用石英ガラスルツボ |
JP4907735B2 (ja) * | 2009-04-28 | 2012-04-04 | 信越石英株式会社 | シリカ容器及びその製造方法 |
JP4903288B2 (ja) * | 2009-05-26 | 2012-03-28 | 信越石英株式会社 | シリカ容器及びその製造方法 |
JP4922355B2 (ja) * | 2009-07-15 | 2012-04-25 | 信越石英株式会社 | シリカ容器及びその製造方法 |
US9133063B2 (en) * | 2009-09-09 | 2015-09-15 | Sumco Corporation | Composite crucible, method of manufacturing the same, and method of manufacturing silicon crystal |
US9003832B2 (en) * | 2009-11-20 | 2015-04-14 | Heraeus Shin-Etsu America, Inc. | Method of making a silica crucible in a controlled atmosphere |
FR2954764B1 (fr) * | 2009-12-30 | 2011-12-30 | Saint Gobain Quartz Sas | Creuset en silice |
JP5777881B2 (ja) * | 2010-12-31 | 2015-09-09 | 株式会社Sumco | シリカガラスルツボの製造方法 |
US8281620B1 (en) * | 2011-04-27 | 2012-10-09 | Japan Super Quartz Corporation | Apparatus for manufacturing vitreous silica crucible |
JP7171600B2 (ja) | 2017-03-16 | 2022-11-15 | コーニング インコーポレイテッド | ガラス溶融物の表面上の気泡の寿命を減少させる方法 |
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- 2000-03-30 WO PCT/JP2000/002010 patent/WO2000059837A1/ja active IP Right Grant
- 2000-03-30 EP EP20000912964 patent/EP1094039B1/en not_active Expired - Lifetime
- 2000-03-30 US US09/701,427 patent/US6553787B1/en not_active Expired - Lifetime
- 2000-03-30 KR KR10-2000-7013501A patent/KR100383796B1/ko not_active IP Right Cessation
- 2000-04-01 TW TW089106130A patent/TWI230696B/zh active
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JPH01157427A (ja) | 1987-12-15 | 1989-06-20 | Toshiba Ceramics Co Ltd | 石英ガラスルツボの製造方法 |
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---|---|---|---|---|
US6886364B2 (en) * | 2000-05-31 | 2005-05-03 | Heraeus Quarzglas Gmbh & Co. Kg | Method for producing quartz glass crucible |
JP2003034593A (ja) * | 2001-07-23 | 2003-02-07 | Shinetsu Quartz Prod Co Ltd | シリコン単結晶引上げ用石英ガラスるつぼの製造方法及び装置 |
JP2005206446A (ja) * | 2004-07-16 | 2005-08-04 | Shinetsu Quartz Prod Co Ltd | シリコン単結晶引上げ用石英ガラスるつぼおよびその製造方法 |
Also Published As
Publication number | Publication date |
---|---|
EP1094039B1 (en) | 2015-04-29 |
KR100383796B1 (ko) | 2003-05-14 |
EP1094039A1 (en) | 2001-04-25 |
US6553787B1 (en) | 2003-04-29 |
KR20010052461A (ko) | 2001-06-25 |
EP1094039A4 (en) | 2009-01-28 |
TWI230696B (en) | 2005-04-11 |
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