TWI789471B - Czochralski growth apparatus conversion assembly - Google Patents

Abstract

The present invention relates to a growth apparatus conversion assembly and method for retrofitting and converting a Czochralski growth apparatus, particularly a batch Czochralski growth apparatus into a continuous Czochralski growth apparatus. In particular, an isolation valve is disposed between an upper hopper and a lower hopper in order to maintain conditions in the lower hopper while the upper hopper is being refilled.

Description

Tchaikrasky Grow Unit Conversion Accessories

The present invention relates to a plant conversion kit for converting a Tzochelski growing plant into a continuous Tschicholaski growing plant.

One of the most efficient and economical methods of preparing materials for the manufacture of integrated circuits and photovoltaic solar cells from monocrystalline silicon ingots is the Czochrakski (CZ) method. In a typical CZ process, a silicon charge is placed in a crucible and melted to a liquid state, typically at a temperature of about 1416°C. Then, small crystalline silicon seeds with a predetermined crystallographic orientation are lowered into contact with the melt surface to be gradually withdrawn. Under proper temperature control, liquid silicon condenses on the seed crystal with the same crystallographic orientation as the seed crystal. The seed crystals are then slowly removed from the melt to form a growing silicon ingot with an overall cylindrical shape, a final length of 1 meter or more, and a diameter of several hundred millimeters.

In general, two types of CZ techniques are known, commonly referred to as batch Tchaikolasky and continuous Tchaikolasky. In batch CZ, the amount of charge material required to grow a silicon ingot is melted in a heated crucible at the beginning of the process, an ingot is then pulled to substantially drain the crucible, and then can be The crucible is discarded, or the crucible can be refilled and the process repeated to grow additional silicon ingots, sometimes referred to as a semi-batch process. In addition, a batch recharge process can be used when ingot growth is stopped or when feedstock is added to the crucible to restart growth. In both batch cases, no feedstock material was added during ingot growth. Also, the number of ingots and their length are usually limited by the size of the crucible. In contrast, in a continuous Czochralski (CCZ) growth process, the charge is continuously or periodically replenished during the growth process, resulting in multiple crucibles that can be pulled at one time from a single crucible replenished during growth. ingot. Additionally, since the crucible is replenished during growth, longer and higher quality ingots can be pulled at a time. Crucibles are only discarded after a few ingot cycles and replaced with new ones. Growing multiple ingots of longer length at one time offers economical and procedural advantages, but requires significantly different types of growth apparatus and equipment than those available for batch CZ growth.

The present invention relates to a growing apparatus conversion kit for converting a Tzoikrasky growing apparatus, in particular a batch Tzokrasky growing apparatus, into a continuous Tchaikorasky growing apparatus. The growing device conversion kit including a feeder assembly includes: a feeder connectable to the growth chamber and configured to supply solid feedstock into the growth chamber; a lower hopper connected to the feeder and configured to supply solid feedstock to the growth chamber In the feeder; at least one upper hopper is removably attached to the lower hopper and is configured to supply solid material to the lower hopper; and a feed separation valve is located between the upper hopper and the lower hopper, The feed separation valve group is configured to maintain the condition of the lower hopper while the upper hopper is being replenished. Furthermore, a shut-off valve can also be located between the upper hopper and the lower hopper. In certain embodiments, the growth apparatus conversion assembly further comprises a feed port configured in a side wall of the growth chamber of the batch Tchaikrasky growth apparatus for coupling to the feeder assembly. In certain embodiments, the growth apparatus conversion assembly further comprises a feed spout configured to be fixedly positioned within the growth chamber of the batch Tchaikorasky growth apparatus for directing the solid feedstock from the feeder assembly into the crucible of the growth chamber. The feed spout may have a sloped lower end for receiving the solid feedstock from the feeder and feeding the solid feedstock into the crucible.

The present invention further relates to a method, wherein there is provided a batch Tchaikorasky growth apparatus having a growth chamber comprising: a chamber housing having a top wall and at least one side wall; a crucible containing a melt within the chamber housing; and A pull mechanism retractably supports the seed crystal to contact the melt. The method further comprises providing a growing plant conversion kit comprising a feeder assembly comprising: a feeder connectable to the growth chamber and configured to supply solid feedstock into the growth chamber; a lower hopper connected to the feed and configured to supply solid material to the feeder; at least one upper hopper is removably attached to the lower hopper and configured to supply solid material to the lower hopper; and a feed separation valve is located at the Between the upper hopper and the lower hopper, the feed separation valve group is configured to maintain the lower hopper while the upper hopper is being refilled. The method further includes coupling the feeder fitting of the growth device adapter to the sidewall of the growth chamber. In certain embodiments, the growth apparatus conversion assembly further comprises a feed port, and coupling the feeder assembly includes placing the feed port in a side wall of the growth chamber of the batch Tchaikrasky growth apparatus and placing the feeder assembly The feeder is coupled to the feed port. In certain embodiments, the growth apparatus conversion kit further comprises a feed spout, and the method further comprises disposing the feed spout within the growth chamber of the batch Tchaikorasky growth apparatus. In some embodiments, the growth device conversion kit further comprises a feeder spout, and the method includes fixedly disposing the feeder spout within the growth chamber of the batch Tchakova growth device for receiving The solid feedstock is directed into the crucible of the growth chamber. The feed spout may have an inclined lower end for receiving the solid feedstock from the feeder and feeding the solid feedstock into the crucible. In this way, the method provides for the conversion of a Tchaikorasky growing device, in particular a batch Tchaikorasky growing device, into a continuous Tchaikorasky growing device.

It should be understood that the above summary of the invention and the following embodiments are only for illustration, and are used to provide further description of the present invention, as proposed in the claims.

100‧‧‧Growing device conversion accessories

110‧‧‧feeder accessories

120‧‧‧Hopper

122‧‧‧cover

124‧‧‧Coupler

130‧‧‧Lower Hopper

140‧‧‧Feeder

142‧‧‧Feeding tray

144‧‧‧bellows

145‧‧‧track

148‧‧‧chamber separation valve

150‧‧‧Feeding separation valve

152‧‧‧Feeding closing valve

156‧‧‧Plinth

160‧‧‧Feed port

170‧‧‧Feeding nozzle

172‧‧‧lower end

190‧‧‧chamber shell

199‧‧‧crucible

300‧‧‧Procedure

305, 310, 315, 320, 325‧‧‧steps

The specific embodiments herein can be better understood by referring to the following description in conjunction with the accompanying drawings, in which the same reference numerals indicate identical or functionally similar accessories, wherein: Figure 1 is an embodiment of the growing device conversion accessory of the present invention The schematic diagram.

Figure 2 is an exploded view of an embodiment of the growth device conversion accessory of the present invention.

Figure 3 illustrates an exemplary method for converting a batch Tzoikrasky growth apparatus to a continuous Tchaikorasky growth apparatus in accordance with an embodiment of the present invention.

It should be understood that the foregoing drawings are not necessarily to scale, and in some instances there may be a somewhat simplified representation of various preferred features illustrative of the basic principles of the disclosure. The specific design features of this disclosure, including, for example, specific dimensions, orientations, locations and shapes, will be determined in part by the particular application and use environment.

As mentioned above, batch CZ method growth apparatus is structurally and operationally very different from CCZ method growth apparatus. Therefore, implementing continuous growth processes in batch growth devices requires, in some cases, relatively costly modifications to the devices. For example, it may be necessary to modify a conventional batch Tchachelski growth apparatus to include a mechanism for melting additional charge material in a continuous or semi-continuous manner without adversely affecting the growth of the ingot. This may also require providing access to the interior of the growth chamber, for example via the addition of ports that are not normally present in most bulk CZ devices. Considerable modifications also need to be taken into account for the mechanical and thermal changes in the relatively low temperature feedstock entering the growth plant system during the growth phase of the ingot. Furthermore, in order to reduce the disadvantages caused by the act of simultaneously replenishing the feedstock while the grain is growing, it is preferable to use a typical CCZ growth apparatus with an outer or annular molten zone for the delivery of the added material and to make the silicon ingot Pulled out crucibles with separate internal growth regions to replace the quartz crucibles used in traditional batch CZs. Otherwise, the length and/or number of grown ingots may be limited by the size of the crucible. Other major structural and procedural modifications may also be necessary. Therefore, the implementation of growing silicon ingots by means of CCZ growth equipment usually necessitates the purchase of growth equipment specifically designed for this purpose, resulting in considerable cost and additional space required for physical handling. Currently, no feasible solution is available for effectively and efficiently converting an existing bulk CZ growth setup to a CCZ growth setup.

The present invention relates to conversion kits and methods for retrofitting a batch Zzoicolaski growing unit to convert the growing unit to a continuous Zzoicolaski growing unit. Although the kit and method are most particularly useful for converting from a batch Tchaikorasky unit to a continuous unit, the techniques described herein can also be used to upgrade various types of continuous Tchaikorasky growing units. Thus, the Tschicholassky growth apparatus to be modified can be any apparatus known in the art, and the growth apparatus can have various types of configurations and components to produce ingots, especially silicon ingots, as desired. More preferably, the growth apparatus is a batch Tzokrassky growth apparatus configured to produce silicon ingots in a step-wise process in which ingot growth is interrupted to replenish additional Feedstock is given to the crucible for preparing additional ingots.

Typically, a Tschicholassky growth apparatus to be retrofitted includes a growth chamber in which an ingot, such as a silicon ingot, can be produced. In particular, the growth chamber comprises a chamber shell having a top wall and one or more side walls forming a heatable space in which a crucible containing a feedstock is provided. For example, the crucible may contain a silicon-containing precharge that is subsequently melted in the crucible within the growth chamber. The crucible, which can be supported from below by one or more pedestals and can be rotated if desired, can be any crucible known in the art for crystal growth, capable of containing solid and liquid materials, particularly solid silicon and liquid Silicon. For example, the crucible may be a quartz crucible, or may be a graphite crucible with a quartz liner. The crucible can also have any cross-sectional shape depending on the geometry of the crystal growth system, but it typically has a circular cross-sectional shape.

In some embodiments, the crucible includes at least two regions, each separated by a wall or other partition and having at least one opening, such as a notch, hole, or tube, to provide restricted fluid communication between the regions. For example, a crucible may include walls that divide it into two regions, an inner region referred to herein as an inner growth region, and an outer region referred to herein as an outer feed region. These regions are in fluid communication with each other. The inner region is where the growth of the ingot begins and the ingot grows (eg, pulls), while the outer region feeds additional material into the inner region as the ingot grows. Thus, while material is removed from the inner growth region by the crystallization process, new material can enter from the outer feed region. More preferably, the inner growth region and/or the outer feeder region comprise a solid silicon-containing precharge to be melted and may also comprise at least one dopant material including, for example, phosphorous, boron, gallium, indium, aluminum, arsenic or antimony.

The Tchaikorasky growth plant to be retrofitted and converted also includes at least one system from which the growth of crystalline ingots can be initiated. For example, the device may further comprise a pulling mechanism comprising a retractable cable on which a small seed, such as a silicon crystal, is supported. With this mechanism, a seed crystal having a predetermined crystallographic orientation can be lowered into contact with the molten material (eg, raw material) contained in the crucible, and then gradually withdrawn. Under proper temperature control, the liquid material with the same crystallographic orientation will condense on the seed crystal, thereby starting the growth of the ingot. The seed crystals are then slowly removed from the melt to form a grown ingot of desired final length and diameter, one or more load cells supporting the pull mechanism may also be used with control responsive to the load cells , used to activate the feedstock supply from the solid feedstock delivery system to the growth unit.

As noted above, typically a precharge of raw material is provided to a crucible in a growth chamber and melted, and growth is then initiated from the melt. In some embodiments, a Tschicholaski growth plant (eg, a batch CZ growth plant) to be retrofitted may further include a system for delivering feedstock to the crucible to provide a precharge when no growth is occurring. Any pre-charged delivery system capable of providing feedstock such as silicon (including metallurgical-grade silicon or solar-grade silicon), which may also include at least one dopant material such as phosphorus, before or during growth or after growth can be used, boron, gallium, indium, aluminum, arsenic, or antimony. For example, solid feedstock as a pre-charge can be provided via gravity feed from a hopper through a feed tube that can transfer feedstock from the hopper to a crucible in the growth chamber. A feed opening of the housing, eg in the top wall, may provide a channel through which the feeder delivers the pre-charge. The feed port may provide a seal so that conditions within the growth chamber are maintained as the precharge is replenished to the crucible.

The Tschicholaski growth apparatus to be modified may also include a heat shield positioned above the crucible. The heat shield set is configured to protect the growing ingot from being overheated into a molten charge in the crucible, so it has a low thermal conductivity material capable of withstanding the high temperatures and conditions within the growth apparatus. Various types of heat shields known in the art can be used in the growth apparatus, the size and shape of which will depend on the geometry of the growth apparatus. For example, for a crucible having a circular cross-sectional shape and used to form a silicon ingot having a substantially circular cross-sectional shape, the heat shield preferably also has a circular cross-sectional shape and is generally geometrically cylindrical Or conical, in particular, the heat shield may have an inverted conical shape with a greater cross-sectional area at the top of the heat shield than at the bottom and a diameter at the bottom large enough to allow the passage of a growing ingot.

In accordance with an embodiment of the present invention, a growth plant conversion kit is provided to convert a batch Tschakova growth plant to a continuous Tschakova growth plant. The growth apparatus conversion kit includes a feeder kit for providing solid feedstock as the silicon ingot grows, and may also include additional kits, which will be described in more detail below. The set of feeder assemblies constitutes a growth chamber connected or otherwise coupled to a batch Tzokrasky growth apparatus such that the growth apparatus is continuously supplied with feedstock as the ingot is grown. More preferably, the feeder subassembly constitutes a side wall of the chamber shell attached to the growth apparatus, so configured that addition of feedstock during growth has minimal impact on the ingot growth process or on the characteristics of the ingot growth.

In particular, the feeder assembly of the growing plant conversion assembly of the present invention comprises a feeder, a lower hopper and at least one upper hopper. In some embodiments, a feeder assembly may be connected to the growth chamber of a batch Tchaikrasky device at the feeder, configured to deliver solid feedstock into the growth chamber, as described in more detail below. The lower hopper is connected to the hopper and positioned to feed solid material into the hopper, preferably from above (i.e. gravity fed), but other methods of feeding solid material into the lower hopper may also be used, such as from a remote The conveyor or feeding system of the upper hopper. Additionally, the upper hopper is connected to the lower hopper and positioned to feed solid material into the lower hopper, which is also preferably gravity fed from above. In this way, the solid feedstock contained in the upper hopper can be fed into the lower hopper, and then the solid feedstock can then pass through the feeder for delivery into the growth chamber of the Zacholaski growth apparatus.

The upper and lower hoppers are containers for holding solid feedstock and may have any shape or configuration known in the art. More preferably, the hopper has a cylindrical upper section and a funnel-shaped conical lower section and has an opening (e.g., a spout) through which the solid material can pass. Covers or lids may also be included to prevent dust or other contaminants from entering the solid feedstock. Furthermore, the upper and lower hoppers may be the same or different, and their capacity may vary according to, for example, cost, space available, and size and number of ingots to be prepared. In some embodiments, the upper hopper may be smaller than the lower hopper. In this way, the high capacity lower hopper is sufficient to grow the required ingots, while the lower capacity upper hopper will be easily removable, as described below. Also, the lower hopper must be able to withstand conditions such as vacuum and/or heat to provide solid feedstock in the proper state to enter the feeder and then into the growth chamber of a batch Tchaikoraski growth apparatus.

Furthermore, in embodiments of the invention, the upper hopper can be removed from the lower hopper, for example during feeding of solid feedstock from the feeder to the growth chamber. In particular, the feeder assembly of the growing plant conversion assembly may include an upper hopper that may be configured to be separate from the lower hopper for delivery or movement away from its location to provide material to the lower hopper. For example, the upper hopper may be physically separated from the lower hopper and relocated or otherwise transported to a location where it may be refilled or used for maintenance/repair of the hopper accessories. Alternatively or additionally, in some embodiments, the upper hopper may be steered laterally (e.g., moving along a track) or pivoted (e.g., about The rotation axis rotates) to move away from the lower hopper to a position where the solid material is no longer delivered to the lower hopper, or where the material is refilled into a different lower hopper. In this second position, refilling or other implementation of the upper hopper may take place. If the feeder assembly includes multiple upper hoppers, the upper hoppers may be removed and subsequently or simultaneously replaced with different upper hoppers (eg, via a turntable or other means).

To remain in the lower hopper when the connected upper hopper is removed, the feeder assembly also includes a feed separation valve between the connected upper and lower hoppers so that it can be closed if the upper hopper is removed And/or seal the feed separation valve, thereby maintaining the state provided in the lower hopper. When the removed upper hopper is reconnected or replaced, the valve can be reopened to re-establish the inclusion of both hoppers in the feeder assembly. Therefore, after the upper and lower hoppers are connected, the state of feeding solid material to the feeder and the growth chamber will be established in the feeder assembly, by first closing the feed separation valve to remove the upper hopper to isolate the upper hopper And maintain the state of the lower hopper and feeder. In this way, when a detached top hopper is replenished or serviced, solid feedstock can continue to be supplied to the growth chamber without interruption, and when reconnected, the state of the top hopper can be established without significantly affecting the state.

Additionally, a feed shut-off valve (sometimes also called a discharge valve or dump valve) may be included between the upper and lower hoppers to provide control and regulation of the flow of solid material. For example, with the feed separation valve open, the feed shut-off valve can be opened to change the flow rate of the solid material into the lower hopper. If the upper hopper is removed, the feed will first be stopped by closing the feed shut-off valve, then the feed separation valve can be closed to maintain the status in the lower hopper. The feed shut-off valve also prevents solid material from interfering with the operation of the separation valve.

As noted above, the feeder assembly of the growth apparatus conversion assembly includes a feeder for feeding solid feedstock into the growth chamber, and more specifically, into the crucible of the batch Tchaikorasky growth apparatus that is to be converted into a continuous Tchaikrasky growth device. For example, the feeder may be a trough system through which a controlled amount of solid silicon feedstock is delivered to the crucible. The feeder may comprise at least one delivery point depending from the crucible. When the crucible includes an inner growth region and an outer feed region, the feeder preferably provides material to the outer feed region of the crucible in order to minimize disturbance of the ingot growing or being pulled from the molten silicon.

In more detail, the feeders of the growth apparatus conversion kit deliver solid feedstock into the growth chamber, and a variety of different types of feeders may be used. For example, the feeder may include a feeder pan that is both insertable into the growth chamber and removable from the growth chamber back into the feeder assembly. In one embodiment, the feeder tray may be removable for insertion into the growth chamber while the feeder itself is at rest. In other embodiments, the feeder pan is stationary relative to the feeder, while the feeder (and thus the corresponding feeder assembly) is movably positioned along the feeder track. In this manner, the feeder assembly and feeder can be suitably positioned to couple to the growth chamber of a batch Tchaikrasky growth apparatus and provide solid feedstock into the growth chamber.

The feed pan can be formed from any material known in the art that is capable of withstanding the temperatures and conditions in a high temperature crystal growth furnace, including, for example, high modulus, non-polluting materials such as silicon carbide. More preferably, the feed pan includes a receiving section connected from the lower hopper along an injector section for receiving material, for example via a feed port and/or a separation valve as described below. The spout of the lower hopper may be located in the side wall of the receiving section. In some embodiments, the cross-section of the injector section is smaller than the cross-section of the receiving section. Furthermore, the injector section may have a lower end having a concave cross-sectional shape, including for example having a V-shaped lower end with its sidewalls opposite the vertical. The slope of the bottom of the recess may vary depending, for example, on the amount of raw material fed into the growth chamber. For example, the walls of the injector section may have a slope of between about 30° and about 60°. Additionally, the receiving section of the feed pan may be supported by vibrators to assist in conveying the material. For example, the vibrator may be supported on a hopper of the container, and the hopper may be provided in the feed chamber by at least one load cell capable of measuring the current amount of material. Thus, the feed pan may be a vibrating feeder with vibration-induced motion of the solid material along the feed pan, or the feed pan may be a rotating feed tube configured to move the solid material along an axis of rotation.

While the feeder assembly and the feeder are movable relative to the growth chamber along the feeder track, the feeder may also include one or more bellows to provide for expansion and contraction as the feeder moves. In this way, by displacement of the bellows, the feeder can be retracted or moved towards the growth chamber without disconnecting the feeder from the growth chamber. Additionally, for vibratory feed pans, the bellows can also provide damping properties to prevent the transfer of vibrational energy to the growth chamber, which could lead to defects in the growing ingot. Additionally, if required, a shielding system can also be used, inserted between the feed pan and the bellows, to protect the bellows from any potential loose solid material.

In some embodiments, the growing device conversion kit of the present invention further includes a chamber separation valve configured to maintain conditions within the growth chamber when the feeder kit is removed. In this way, process conditions (eg, ingot growth conditions) that exist on one side of the valve can be separated from different process conditions (eg, feedstock maintenance conditions) on the other side. As will be understood by those skilled in the art, various different types of valves may be used, such as spool valves, gate valves, pancake valves, and the like. For example, the chamber separation valve can be connected to a feed port in the growth chamber, or can be connected to the feeder of the feeder fitting, discussed in more detail below. In a preferred embodiment, the hopper assembly includes a chamber separation valve connected to the hopper to isolate the conditions present within the hopper assembly. For this embodiment, the feeder assembly can be vacuum sealed to the growth chamber at the chamber separation valve so that the feeder can be inserted into the growth chamber and also moved from the growth chamber back into the feeder assembly through the chamber separation valve. Wherein the chamber separation valve can be any valve known in the art, but is preferably a gate valve with an expandable water-cooled gate, such as those disclosed in U.S. Patent Application Publication Nos. 2011/0006235, 2011/0006236 and 2011/0006240. Describe it fully. In some embodiments it may be advantageous to use isolation valves, the use of some valves is optional, however in another embodiment of the invention the growth system does not include any isolation valves.

In some embodiments, the growth apparatus conversion kit further includes a feed port configured in a housing of the growth chamber and through which feedstock, such as silicon, is delivered as the silicon ingot grows. While the feedport may be located anywhere along the chamber housing, including in at least one of the side walls or the top wall, depending on, for example, the configuration of the batch Tchaikrasky growing apparatus, it is preferred that the feedport be located at On the side wall of the chamber shell of the growth chamber to facilitate the transportation of raw materials. Furthermore, it is preferred that the feed opening be located at a height in the side wall of the growth chamber such that the feedstock is delivered to the crucible without significantly affecting the melt formed therein. For example, preferably, the feedport is positioned such that feedstock enters the growth chamber from a feeder of the feeder assembly at a height substantially similar to that of the crucible. Additionally, it is also preferred that the feed opening is positioned such that the feedstock enters the crucible substantially horizontally. For example, the feedport tends to be at a height such that the center of the port forms the entire delivery path, which has an angle between 0° (i.e. horizontal) and about 45°, preferably between about 0° and about 30° , and even more preferably between about 0° and about 20°. Thus, a slight inclination tends to feed the material into the crucible slowly and consistently without sticking or clogging, but not at a high enough velocity to cause splashing or rebound. Additionally, the height and/or angle of the feed path can be adjusted within these parameters, including during material delivery. By positioning the feed ports so that the feedstock is delivered from the side of the growth chamber at a low height and entry angle, it is possible to convert from a batch Tchaikorasky growth unit to a continuous Tchaikorasky growth process using the growth unit conversion kit of the present invention to produce ingots with improved overall properties.

In some embodiments, the growing device conversion kit further includes a feed port secured in place within the growth chamber of the batch Tchaikrasky growing device. The feedport set is configured to receive solid feedstock from the feeder of the feeder assembly and direct the feedstock into the crucible in the growth chamber. For example, the feedwell may have a sloped lower end and a spout above the crucible so that raw material provided from the feeder fitting may enter the feedwell and be added to the crucible without considerable splashing. The slope of the lower end of the feedwell can vary depending on, for example, the height of the feedwell above the crucible and the desired feedstock addition rate. For example, the sloped lower end may be sloped at an angle between about 30° and about 60°. For a crucible having an inner zone and an outer zone, preferably the spout of the feedport is arranged above the outer feed zone. The feedwell container may comprise any material known in the art to withstand the temperatures and conditions found in high temperature crystal growth furnaces, including, for example, high modulus, non-polluting materials such as silicon carbide.

Specific embodiments and assemblies of the growing device conversion kit of the present invention are shown in Figures 1-3 and discussed below. However, it is obvious to those skilled in the art that these examples are only illustrative and not restrictive. Many modifications and other embodiments are within the purview of one of ordinary skill in the art and are within the scope of the invention. Additionally, those skilled in the art will understand that the specific configuration is exemplary and the actual configuration will depend on the specific system. Using no more than routine experimentation, those skilled in the art will also be able to identify and recognize equivalents to the specific accessories shown.

FIG. 1 is a side view of a growth apparatus conversion accessory 100 according to an embodiment of the present invention. As shown, the fittings include a feeder fitting 110 , a feed opening 160 and a feed spout 170 . FIG. 2 is an exploded perspective view of a growing device conversion kit 100 without a feedport. As shown, feeder assembly 110 includes upper hopper 120 positioned above and removably connected to lower hopper 130 , which is positioned above and connected to feeder 140 as shown. In this way, the solid feed material is gravity fed from the upper hopper to the lower hopper and feeder. In this particular embodiment, upper hopper 120 has a smaller capacity than lower hopper 130, and both have an overall cylindrical shape with a generally conical funnel-shaped spout. The upper hopper 120 includes a cover 122 at the top and also includes a coupler 124 that can be attached to and detached from the lower hopper. A feed separation valve 150 is located between the upper hopper 120 and the lower hopper 130 and, when open, allows both hoppers and feeders to be under similar feeding conditions (temperature, vacuum, etc.), and when closed, separates the lower hopper from the feeder. Detaches from the top hopper and allows the top hopper to be removed without changing the feeding conditions. In addition, a feed shut-off valve 152 is also disposed between these hoppers to allow the flow of solid feed material from the upper hopper 120 to the lower hopper 130 to be interrupted or adjusted as desired.

In the particular embodiment shown in Figures 1 and 2, the feeder 140 of the feeder assembly 110 can be connected to the chamber housing 190 of a batch Tchaicolaski growing apparatus for retrofit and conversion to a continuous Tchaicolaski growing apparatus. Lasky growth apparatus. In particular, the feeder assembly also includes a track 145 on which the feeder 140 is positioned such that the feeder assembly can be moved along the track to a position adjacent the chamber housing. The feeder assembly 110 may optionally rest on the base 156 for support and placement of the feeder assembly at the appropriate height of the target Tchaikorasky growing device. The height of the base can be fixed or adjustable.

The feeder 140 includes a feed pan 142 that receives solid feedstock from the lower hopper 130 and delivers the feedstock to the growth chamber of the batch Tchaikrasky growth apparatus. In some embodiments, such as the embodiment shown in Figures 1 and 2, when the feed pan is movable to a position for delivering solid feedstock into the growth chamber, the feed pan is fixed relative to the feed fitting, and The feed fitting is moveable into position along track 145 . The feeder 140 also includes a bellows 144 that expands and contracts as the feeder assembly moves along the track 145 and that also provides vibration damping when the feeder pan is operated by vibratory feeding.

As shown in FIG. 1 , the growth apparatus conversion assembly 100 also includes a feed port 160 located in the side wall of the chamber shell 190 at substantially the same height as the top of the crucible within the growth chamber. As shown in Figures 1 and 2, the feeder 140 also includes a chamber separation valve 148 that is connectable to the feed port 160 and, when closed, maintains the growth chamber when the feeder assembly is removed state in . As the hopper 140 moves along the track 145 , the bellows 144 expand and contract to allow the hopper assembly 110 to move relative to the attached chamber separation valve 148 . In this manner, feed tray 142 is inserted into the growth chamber through feed port 160 . It should be noted that in some embodiments, the feedport may be an optional accessory to the growing device conversion accessory. For example, feedport 160 may not be required if the Tchaikrasky growth apparatus to be retrofitted and converted already includes ports in the side walls of the growth chamber.

As also shown in FIGS. 1 and 2 , the growth apparatus conversion kit 100 further includes a feed nozzle 170 fixedly disposed within the growth chamber of the Tchaikraski growth apparatus so as to protrude above the crucible 199 . As shown, the feed spout 170 is positioned at an elevation to provide a substantially horizontal flow path from the feeder 140 . Solid feedstock from the feeder passes through the feed port 160 and then through the feed spout 170 to be directed into the crucible of the Tchachelsky growth apparatus. Feed spout 170 includes a sloped lower end 172 for receiving solid feedstock from a hopper, and the solid feedstock may flow downwardly into crucible 199 .

As noted above, the present invention also relates to methods of converting a Tchaikorasky growth plant, in particular a batch CZ growth plant to a continuous Tchaikorasky growth plant. Figure 3 shows an example simplification of the method. For example, procedure 300 may begin at step 305 and continue to step 310, wherein, as described in detail above, a batch Tchaikorasky growth apparatus having a growth chamber is provided. While batch Tchaikrasky growth apparatus can vary in specific configurations and fittings, in some embodiments, a growth chamber includes a chamber shell having a top wall and at least one side wall, a crucible containing a melt within the chamber shell, and a Pulling mechanism for retractably supporting the seed crystal to contact the melt.

At step 315, the method also includes providing a growing plant conversion assembly including a feeder assembly, as described in detail above. Any of the accessories described above may be used in the method of the present invention. In some embodiments, the growing apparatus conversion assembly includes: a feeder assembly; a feed port disposed in a side wall of the chamber housing (which may be optional in some embodiments); and a feed spout fixedly disposed in the growth chamber housing. The chamber is used to introduce the solid raw material flow into the crucible. The feeder assembly includes a feeder connectable to the growth chamber and configured to feed a solid feedstock into the growth chamber. The feeder assembly also includes a lower hopper connected to the feeder and configured to feed solid material to the feeder, and at least one upper hopper removably connected above the lower hopper and configured to feed solid material to the lower hopper middle. In addition, the feeder assembly also includes a feed separation valve located between the upper hopper and the lower hopper, configured to hold the upper hopper in the lower hopper while it is being filled.

At step 320, the method also includes coupling a feeder fitting of the growth apparatus conversion fitting to a sidewall of the growth chamber, as described in detail above. In embodiments where the growing apparatus conversion assembly includes a feedport, coupling the feeder assembly includes disposing the feedport in a side wall of a growth chamber of a batch Tchaikorasky growing apparatus, and coupling the feeder of the feeder assembly to the feedport . Coupling may also include moving the feeder assembly along the track to a position adjacent the chamber housing of the batch Tchaikrasky growing device. The bellows of the feeder can be adjusted by expanding and/or contracting as needed to couple the feeder assembly to the growth chamber. An optional base is also available to adjust the height of the feeder fitting for easier coupling. Routine 300 then ends at step 325 .

It should be noted that while certain steps within procedure 300 may be optional as described above, the steps shown in FIG. 3 are merely examples for illustration and certain other steps may be included or excluded as desired. step. In addition, although steps in a specific order are shown, such ordering is merely illustrative, and any suitable arrangement of steps may be made without departing from the scope of the embodiments of the present application.

The use of a growth unit conversion kit provides significant advantages in a method of converting a batch Tchaikrasky growing unit to a continuous Tchaikorasky growing unit. For example, a batch process user may wish to grow silicon ingots in a continuous process without purchasing entirely new growth equipment. Existing batch units can be retrofitted without significant changes to existing growth chambers and their accessories. Furthermore, once coupled to the growth chamber, the growth device conversion kit of the present invention allows for uninterrupted processing of silicon ingots. In particular, since the feeder assembly includes two solid raw material hoppers separated by a separation valve, solid silicon can be fed through the feeder from the upper hopper to the lower hopper and into the crucible of the growth apparatus. When growing silicon ingots, the upper hopper can be removed when empty by closing the feed separation valve, allowing the same or additional ingots to continue growing while the upper hopper is refilled. Once filled, the upper hopper can be reconnected, the feed separation valve can be opened, and feeding can continue from the upper hopper to the lower hopper. This action can be repeated many times without interrupting the growth process of the silicon ingot. Ingots of virtually unlimited length can be grown, as feedstock is continuously replenished during growth by refilling the removable and detachable upper hopper. This is not possible in the batch Tchaikorasky process, where the ingot length is limited by the size of the crucible, and generally cannot be achieved in the standard continuous Tchaikorasky process, where the ingot length is limited by the filling of the crucible hopper size limitations. Other advantages will become apparent to those of ordinary skill in the art, given the benefit of this disclosure.

The foregoing description of the preferred embodiment of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise aspects disclosed. Modifications and variations are possible in light of the above teachings or practice of the invention. The embodiment was chosen and described in order to explain the principles of the invention and its practical application, to enable others skilled in the art to utilize the invention in various embodiments and with various modifications as is suited to the particular use contemplated. It is intended that the scope of the invention be defined by the appended claims and their equivalents.

100‧‧‧Growing device conversion accessories

110‧‧‧feeder accessories

120‧‧‧Hopper

122‧‧‧cover

124‧‧‧Coupler

130‧‧‧Lower Hopper

140‧‧‧Feeder

144‧‧‧bellows

145‧‧‧track

148‧‧‧chamber separation valve

150‧‧‧Feeding separation valve

152‧‧‧Feeding closing valve

156‧‧‧Plinth

160‧‧‧Feed port

170‧‧‧Feeding nozzle

172‧‧‧lower end

190‧‧‧chamber shell

199‧‧‧crucible

Claims (22)

A method for converting a growth chamber comprising: providing a batch Tchaikorasky growth apparatus having the growth chamber, comprising: a chamber shell having a top wall and at least one side wall; a crucible containing a a melt; and a pull mechanism to retractably support a seed crystal to contact the melt; providing a growth apparatus conversion assembly including a feeder assembly, comprising: a feeder connectable to the growth chamber and positioned to feed solid feedstock into the growth chamber; a lower hopper connected to the feeder and positioned to feed solid feedstock into the feeder; at least one upper hopper removably attached to the lower hopper and positioned to feed solid feedstock into the lower hopper; and a feed separation valve located between the upper hopper and the lower hopper, the set of feed separation valves configured to remain in the lower hopper while the upper hopper is being refilled, the The feeder fitting of a growing device conversion fitting is coupled to the side wall of the chamber shell. The method described in item 1 of the patent scope of the application, wherein the feeder includes a feeding tray and an injector section, the feeding tray has a receiving section for receiving the solid raw material from the lower hopper, and the injector section Connected to the receiving section and insertable into the growth chamber. The method described in item 2 of the scope of the patent application, wherein the feeding pan is a vibrating feeding pan. The method described in item 2 of the scope of the patent application, wherein the feeding pan is a drum type feeding pan. The method described in item 2 of the scope of the patent application, wherein, in the feeder accessories After being coupled to the side wall of the chamber shell, the feed pan is movable for insertion into the growth chamber. The method of claim 1, wherein the feeder fitting is movable along a feeder track to be coupled to the side wall of the housing. The method of claim 6, wherein the feeder includes bellows configured to expand or contract when the feeder moves along the feeder track. The method described in item 1 of the scope of the patent application, wherein the feeder accessory includes a feed closing valve, and the feed closing valve is located between the upper hopper and the lower hopper. The method described in claim 1, wherein the feeder fitting includes a chamber separation valve, and the chamber separation valve set is configured to maintain the state in the growth chamber when the feeder fitting is removed. The method described in item 9 of the scope of the patent application, wherein the chamber separation valve is a gate valve with an expandable water-cooled gate. The method of claim 9, wherein the chamber separation valve is connected to the feeder of the feeder fitting. The method of claim 9, wherein the feeder includes bellows configured to expand or contract as the feeder moves along the feeder track, and wherein the chamber separation valve is connected to to the bellows of the feeder. The method of claim 1, wherein the growing device conversion assembly further includes a feeder assembly, and wherein coupling the feeder assembly includes configuring the feeder port to the batch Tchaikorasky growing device The side wall of the chamber housing and couples the feeder of the feeder fitting to the feed port. The method described in item 13 of the scope of patent application, wherein the feeder accessory A chamber separation valve is included that is connectable to the feed port and configured to maintain conditions within the growth chamber when the feeder accessory is removed. The method of claim 14, wherein the feeder includes bellows configured to expand or contract as the feeder moves along the feeder track, and wherein the chamber separation valve is connected to The bellows attached to the feeder. The method described in item 13 of the scope of the patent application, wherein the feeder includes a feeding tray and an injector section, the feeding tray has a receiving section for receiving the solid raw material from the lower hopper, and the injector section connected to the receiving section and insertable into the growth chamber via the feed port. The method of claim 1, wherein the growth apparatus conversion further comprises a feed spout, and wherein the method comprises positioning the feed spout within the growth chamber of the batch Tchaikorasky growth apparatus for directing the solid feedstock from the feeder assembly into the crucible of the growth chamber. The method according to claim 17, wherein the feeding nozzle has an inclined lower end for receiving the solid material from the feeder and feeding the solid material into the crucible. The method described in item 17 of the scope of the patent application, wherein, the crucible comprises at least one wall member separating the inner growth region and the outer feeding region, and the wall member has a structure provided between the inner growth region and the outer feeding region At least one opening in restricted fluid communication, and wherein the feed orifice directs a feed of the solid material to the outer feed region of the crucible. The method as described in item 1 of the patent claims, further comprising: melting the solid precharge containing silicon in the crucible to form the melt, The melt is contacted with the seed crystal to initiate growth of the silicon ingot, and as the silicon ingot is grown, the solid feedstock contained in the lower hopper of the growth apparatus adapter is delivered to the crucible. The method of claim 1, wherein the batch Tchaikraski growth apparatus further comprises a solid feedstock delivery system external to the growth chamber, and wherein the method further comprises substituting the feeder assembly for the Solid material delivery system. The method described in claim 1, wherein the method converts the batch Tchaikorasky growth device into a continuous Tchaikorasky growth device.

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