Patent application number | Description | Published |
20090145351 | VITREOUS SILICA CRUCIBLE - The present invention relates to a vitreous silica crucible for pulling up silicon single crystals by a pulling-up process having a first stage and a second stage after the first stage. The crucible comprises a transparent inner layer containing inner layer bubbles, and an outer layer containing outer layer bubbles. The second stage expansion coefficient X | 06-11-2009 |
20090165700 | INNER CRYSTALLIZATION CRUCIBLE AND PULLING METHOD USING THE CRUCIBLE - A vitreous silica crucible for pulling single-crystal silicon, comprising a surface glass layer having a thickness of 100 μm from an inner surface of the crucible, and a glass layer provided below the surface glass layer in a thickness direction of the crucible and extending to a depth of 1 mm from the inner surface of the crucible. The concentration of OH groups in the surface glass layer is 90 ppm or less, and the concentration of OH groups in the glass layer is equal to or more than 90 ppm and equal to or less than 200 ppm. The bubble content in the glass layer is 0.1% or less. | 07-02-2009 |
20090165701 | VITREOUS SILICA CRUCIBLE FOR PULLING SINGLE-CRYSTAL SILICON - A vitreous silica crucible for pulling single-crystal silicon, which is formed of vitreous silica and has a bottomed cylindrical shape, wherein, in a liquid-level movement range in the inner surface of the crucible, ranging from a position corresponding to the liquid surface level of a silicon melt at the time of stating the pulling of single-crystal silicon to a position corresponding to the liquid surface level of a silicon melt at the time of finishing the pulling of single-crystal silicon, the concentration of an OH group included in the vitreous silica is higher in an erosion thickness portion of the inner surface of the crucible than that in the range lower than the liquid surface level which is positioned below the liquid-level movement range | 07-02-2009 |
20100000465 | METHOD FOR PRODUCING VITREOUS SILICA CRUCIBLE - A method is provided for producing a vitreous silica crucible having excellent shape formability and fewer internal bubbles without excessively heating the curved portion and the bottom part. The method comprises arc melting a quartz powder molded product loaded in a rotating mold while performing vacuum suction, wherein the electrode is moved sideways with respect to the mold center line upon the initiation of arc melting or during the arc melting, and the arc melting is performed at an eccentric position, and preferably the time for total heating is limited to 60% or less of the total arc melting time. A vitreous silica crucible produced by this method is also provided. | 01-07-2010 |
20100005836 | METHOD FOR PRODUCING QUARTZ GLASS CRUCIBLE - A method of producing a quartz glass crucible by arc melting a quartz powder molded product loaded on the inner side of a mold while performing vacuum suction, includes initiating the melting of quartz powder from the rim edge of a quartz powder molded product, subsequently lowering the arc electrode or raising the mold to heat and melt the sections on the downside of the rim edge. The method is preferably carried out such that the inner surface of the crucible is sealed within a time corresponding to 10% of the total arc time starting from the initiation of arc melting, and the seal thickness is 3 mm or less. The quartz glass crucible thus produced is useful for the pulling up of silicon single crystals and has a uniform glass layer with fewer internal bubbles. | 01-14-2010 |
20100071417 | ARC DISCHARGE METHOD, ARC DISCHARGE APPARATUS, AND FUSED SILICA CRUCIBLE MANUFACTURING APPARATUS - An arc discharge method of the present invention includes the steps of: heating and melting a non-conductive object by arc discharge using a plurality of carbon electrodes in an output range of 300 to 12,000 kVA; and setting a ratio of the distance between a contact position at which the carbon electrodes come in contact with each other and a front end to the diameter of the carbon electrode during the start of the arc discharge to be in the range of 0.001 to 0.9. | 03-25-2010 |
20100071613 | METHOD AND APPARATUS FOR MANUFACTURING FUSED SILICA CRUCIBLE, AND THE FUSED SILICA CRUCIBLE - A method of manufacturing a fused silica crucible by heating and melting a vitreous silica powder compact shaped into a mold using arc discharge of electrodes arranged around a rotation shaft of the mold, includes the steps of: arranging the electrodes in a ring shape, and setting a ratio W/R of a horizontal distance W between the electrode front end and the surface of the vitreous silica powder compact to a vitreous silica powder compact opening radius R, for at least a predetermined time during arc heating, to be in the range of 0.002 to 0.98. | 03-25-2010 |
20100089308 | SILICA GLASS CRUCIBLE AND METHOD FOR PULLING SINGLE-CRYSTAL SILICON - A silica glass crucible used for pulling single-crystal silicon, which includes a cylindrical straight body part, a bottom part and a curved part located between the straight body part and the bottom part, wherein the curvature radius of the inner wall surface of the curved part is 100 to 240 mm. Variation of the wall thickness W of the curved part is preferably 0.1 to 1.4 mm/cm. | 04-15-2010 |
20100126407 | SILICA GLASS CRUCIBLE AND METHOD FOR PULLING SINGLE-CRYSTAL SILICON - A silica glass crucible used for pulling single-crystal silicon, which includes a cylindrical straight body part, a bottom part and a curved part located between the straight body part and the bottom part, wherein the curvature radius of the inner wall surface of the curved part is 100 to 240 mm. Variation of the wall thickness W of the curved part is preferably 0.1 to 1.4 mm/cm. | 05-27-2010 |
20100162943 | SILICA GLASS CRUCIBLE AND METHOD OF PULLING SILICON SINGLE CYRSAL WITH SILICA GLASS CRUCIBLE - In a silica glass crucible used for pulling a silicon crystal, a circumferential maximum tolerance of each of bubble content, wall thickness and transmission as measured over a full circumference of the crucible at a same height position is not more than 6%. | 07-01-2010 |
20100236473 | VITREOUS SILICA CRUCIBLE FOR PULLING SINGLE-CRYSTAL SILICON AND METHOD OF MANUFACTURING THE SAME - In order to provide a vitreous silica crucible which does not employ a crystallization accelerator but is difficult to deform during its use even under high temperature, and is easily manufactured, there is provided a vitreous silica crucible for pulling single-crystal silicon wherein the outer surface layer is formed of a bubble-containing vitreous silica layer, the inner surface layer is formed of a vitreous silica layer whose bubbles are invisible to the naked eye, a surface of the outer surface layer includes an unmelted or half-melted silica layer (abbreviated as a half-melted silica layer), and the center line average roughness (Ra) of the half-melted silica layer is 50 to 200 μm, also preferably, and the thickness of the half-melted silica layer is 0.5 to 2.0 mm. | 09-23-2010 |
20110079047 | APPARATUS AND METHOD FOR MANUFACTURING VITREOUS SILICA CRUCIBLE - Provided are an apparatus and a method for manufacturing a vitreous silica crucible, which enable accurate measurement of a fume generation amount, prevention of deterioration of an inner surface property, and real-time control of a raw material melting state. Provided is an apparatus for manufacturing a vitreous silica crucible | 04-07-2011 |
20110197631 | METHOD AND APPARATUS FOR MANUFACTURING VITREOUS SILICA CRUCIBLE - Provided is a method of manufacturing a vitreous silica crucible, including: an arc fusing process for fusing the silica powder molded body by using arc flames generated from the plurality of carbon electrodes, wherein the arc fusing process is performed in a state of disposing tips of at least a pair of carbon electrodes of the plurality of carbon electrodes closer to a target surface of the silica powder molded body than other carbon electrode tips, and setting distances from each of the tips of the closer carbon electrodes to the target surface, to be equal, and the arc fusing process is performed by heating and fusing the silica powder molded body while performing fire polishing, which partially removes an inner surface of the silica powder molded body by using arc flames generated by the closer carbon electrodes. | 08-18-2011 |
20110315071 | VITREOUS SILICA CRUCIBLE - The present invention provides a vitreous silica crucible which can restrain deterioration of crystallinity of a silicon ingot in multi-pulling. Provided is a vitreous silica crucible for pulling a silicon single crystal, the crucible has a wall having, from an inner surface toward an outer surface of the crucible, a synthetic vitreous silica layer, a natural vitreous silica layer, an impurity-containing vitreous silica layer and a natural vitreous silica layer. | 12-29-2011 |
20110315072 | VITREOUS SILICA CRUCIBLE AND METHOD OF MANUFACTURING THE SAME, AND METHOD OF MANUFACTURING SILICON INGOT - Provided is a vitreous silica crucible which can suppress inward sagging and buckling of the sidewall effectively even when time for pulling silicon ingots is extremely long. According to the present invention, provided is a vitreous silica crucible for pulling a silicon single crystal, wherein the crucible has a wall comprising, from an inner surface toward an outer surface of the crucible, a transparent vitreous silica layer having a bubble content rate of less than 0.5%, a bubble-containing vitreous silica layer having a bubble content rate of 1% or more and less than 50%, a semi-transparent vitreous silica layer having a bubble content rate of 0.5% or more and less than 1.0% and having an OH group concentration of 35 ppm or more and less than 300 ppm. | 12-29-2011 |
20120017824 | VITREOUS SILICA CRUCIBLE AND METHOD OF MANUFACTURING SILICON INGOT - The present invention provides a vitreous silica crucible which can suppress buckling and sidewall lowering of the crucible in multi-pulling. According to the present invention, provided is a vitreous silica crucible for pulling a silicon single crystal, comprising a mineralizer on an inner surface of the crucible, wherein the mineralizer contains at least one atoms selected from the group consisting of Ca, Sr, Ba, Ra, Ti, Zr, Cr, Mo, Fe, Co, Ni, Cu, and Ag, and the concentration of the mineralizer on the inner surface is 1.0×10 | 01-26-2012 |
20120037069 | METHOD OF EVALUATING SILICA POWDER, VITREOUS SILICA CRUCIBLE, AND METHOD OF MANUFACTURING VITREOUS SILICA CRUCIBLE - The present invention provides a method of evaluating silica powder which, enables precise prediction of easiness of crystallization of a vitreous silica crucible. According to the present invention, provided is a method of evaluating silica powder including a sample preparation process for preparing a vitrified sample by fusing silica powder at a fusing temperature of 1700 to 1900 deg. C., followed by cooling; a sample heat treatment process for retaining the sample for 30 minutes or more at a temperature of 1400 to 1750 deg. C., followed by cooling; and a sample evaluation process for evaluating a state of opacification of the sample after the sample heat treatment process. | 02-16-2012 |
20120131954 | APPARATUS AND METHOD FOR MANUFACTURING VITREOUS SILICA CRUCIBLE - There are provided an apparatus and a method for manufacturing a vitreous silica crucible which can prevent the deterioration of the inner surface property in the manufacturing process of a vitreous silica crucible. The apparatus includes a mold defining an outer shape of a vitreous silica crucible, and an arc discharge unit having electrodes and a power-supply unit, wherein each of the electrodes includes a tip end directed to the mold, the other end opposite to the tip end, and a bent portion provided between the tip end and the other end. | 05-31-2012 |
20120132133 | VITREOUS SILICA CRUCIBLE - The present invention provides a vitreous silica crucible which can suppress buckling and sidewall lowering of the crucible without fear of mixing of impurities into silicon melt. According to the present invention, provided is a vitreous silica crucible for pulling a silicon single crystal, wherein a ratio I2/I1 is 0.67 to 1.17, where I1 and I2 are area intensities of the peaks at 492 cm | 05-31-2012 |
20120137733 | METHOD AND APPARATUS FOR MANUFACTURING VITREOUS SILICA CRUCIBLE - Provided is a method for manufacturing a vitreous silica crucible and a manufacturing apparatus for the same, which can reduce the amount of bubbles and impurities of a crucible inner surface and enhance a crystallization yield of silicon single crystal. A method for manufacturing a vitreous silica crucible of the invention includes a silica powder supplying process of supplying silica powder in a rotating mold to form a silica powder layer; an arc fusing process of fusing the silica powder layer by arc discharge generated by carbon electrodes; and a fire polishing process of throwing an arc flame toward a target surface of the silica powder layer for surface removal, wherein, in the fire polishing process, the distances from the tips of the carbon electrodes to the target surface is set to be equal. | 06-07-2012 |
20120137964 | VITREOUS SILICA CRUCIBLE - The present invention provides a vitreous silica crucible which can suppress buckling and sidewall lowering of the crucible and the generation of cracks. According to the present invention, a vitreous silica crucible is provided for pulling a silicon single crystal having a wall, the wall including a non-doped inner surface layer made of natural vitreous silica or synthetic vitreous silica, a mineralizing element-maldistributed vitreous silica layer containing dispersed island regions each containing a mineralizing element, and wherein the vitreous silica of the island regions and the vitreous silica of a surrounding region of the island regions is a combination of mineralizing element-doped natural vitreous silica and non-doped synthetic vitreous silica, or a combination of mineralizing element-doped synthetic vitreous silica and non-doped natural vitreous silica, and the inner surface layer is made of vitreous silica of a different kind from that of the island region. | 06-07-2012 |
20120141622 | APPARATUS FOR MANUFACTURING VITREOUS SILICA CRUCIBLE - Provided is an apparatus for manufacturing a vitreous silica crucible which has a structure which can reduce gaps between a partition wall and electrodes inserted into through-holes formed in the partition wall while enabling electrodes to move to adjust a heating temperature of arc discharge. A plate-shaped partition wall | 06-07-2012 |
20120160155 | COMPOSITE CRUCIBLE, METHOD OF MANUFACTURING THE SAME, AND METHOD OF MANUFACTURING SILICON CRYSTAL - The purpose of the present invention is to provide a crucible which has high viscosity at high temperature, and can be used for a long time, and can be manufactured at low cost, and a method of manufacturing the same. The composite crucible | 06-28-2012 |
20120160159 | VITREOUS SILICA CRUCIBLE FOR PULLING SILICON SINGLE CRYSTAL AND METHOD OF MANUFACTURING THE SAME - The present invention provides a vitreous silica crucible which can suppress the sidewall lowering of the crucible under high temperature during pulling a silicon single crystal, and a method of manufacturing such a vitreous silica crucible. The vitreous silica crucible | 06-28-2012 |
20120255487 | VITREOUS SILICA CRUCIBLE AND METHOD OF MANUFACTURING THE SAME - Provided is a method of manufacturing a vitreous silica crucible for pulling a silicon single crystal which can suppress melt surface vibration of silicon melt filled therein and has a long lifetime. The crucible includes a peripheral wall portion, a curved portion and a bottom portion, and has a plurality of micro recesses on the specific region of the inner surface of the peripheral wall portion. | 10-11-2012 |
20120260852 | VITREOUS SILICA CRUCIBLE - Provided is a vitreous silica crucible which has a special region for suppressing vibration of melt surface during pulling of a silicon single crystal and at the same time, a marking capable of accurately monitoring a changed position of the melt surface when passing through the special region. The special region for preventing sloshing of silicon melt is provided on an inner wall of a straight body portion, and the marking is provided at least at an upper end and a lower end of the special region. | 10-18-2012 |
20120272687 | APPARATUS FOR MANUFACTURING VITREOUS SILICA CRUCIBLE - Provided is an apparatus for manufacturing a vitreous silica crucible, which is capable of stably manufacturing a high quality vitreous silica crucible by stabilizing heat generation through an arc discharge. The apparatus for manufacturing a vitreous silica crucible includes a mold that defines a shape of a vitreous silica crucible, carbon electrodes that generate an arc discharge for fusing a silica powder molded body formed in the mold, and a power supply device that supplies power to the carbon electrodes. The power supply device includes a saturable reactor that is provided on a supply path of the power to the carbon electrodes and has variable reactance, and a control device that controls the power supplied to the carbon electrodes by changing the reactance of the saturable reactor. | 11-01-2012 |
20120285372 | VITREOUS SILICA CRUCIBLE FOR PULLING SILICON SINGLE CRYSTAL, AND METHOD FOR MANUFACTURING THE SAME - Provided is a vitreous silica crucible for pulling a silicon single crystal, which stably suppresses surface vibration of a silicon melted solution filled therein and has a long life, and a method for manufacturing the same. The vitreous silica crucible for pulling a silicon single crystal includes a peripheral wall portion, a curved portion, and a bottom portion, wherein a plurality of minute concave portions are formed on a certain area of an inner surface of the peripheral wall portion, and a plurality of bubbles are formed on a lower position of the minute concave portions. | 11-15-2012 |
20120318021 | APPARATUS FOR MANUFACTURING VITREOUS SILICA CRUCIBLE - Provided is an apparatus for manufacturing a vitreous silica crucible, which is capable of stably manufacturing a high quality vitreous silica crucible by stabilizing heat generation through an arc discharge. The apparatus for manufacturing a vitreous silica crucible includes a mold that defines a shape of a vitreous silica crucible, carbon electrodes that generate an arc discharge for fusing a silica powder molded body formed in the mold, and a power supply device that supplies power to the carbon electrodes. The power supply device includes a saturable reactor that is provided on a supply path of the power to the carbon electrodes and has variable reactance, and a control device that controls the power supplied to the carbon electrodes by changing the reactance of the saturable reactor. | 12-20-2012 |
20150027364 | SILICA GLASS CRUCIBLE - Buckling of a vitreous silica crucible | 01-29-2015 |