Creation and use of dynamic state charts in growing single crystal silicon ingots

Abstract

To provide a system and method for enabling monitoring and / or control of various ingot growth parameters, and / or a system and method for providing a visual output of the parameters that is easily accessible by an operator and provides a simple visual overview of an ingot growth system.SOLUTION: A method of growing a single crystal silicon ingot according to the Czochralski method includes providing a melt of silicon in a crucible, pulling a single crystal silicon ingot from the melt, providing a plurality of growth parameters associated with growth of the single crystal silicon ingot, and providing a dynamic statechart including visual representations of the growth parameters, wherein the dynamic statechart is a circular statechart divided into sectors, and wherein each sector is associated with a growth parameter.SELECTED DRAWING: Figure 6

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 879,829, filed July 29, 2019, which is incorporated herein by reference in its entirety. [Technical Field]

[0002] The field of the disclosure relates to methods for growing single crystal silicon ingots, and more particularly to the creation and use of dynamic statecharts that monitor multiple ingot growth parameters. [Background technology]

[0003] Single crystal silicon ingots can be grown by the Czochralski method, in which the ingot is pulled from a silicon melt in an ingot pulling system. Single crystal ingot growth requires several growth parameters to be monitored to ensure successful growth (e.g., to achieve a target ingot diameter without creating dislocations within the ingot). This is particularly true for the continuous Czochralski method, in which the ingot is grown continuously by adding silicon to the melt during ingot growth. The continuous Czochralski method is particularly sensitive to changes in various ingot growth parameters and is difficult to control. Small changes in one parameter can have a cascade of other parameters that can cause the system to lose its equilibrium state.

[0004] What is needed is a system and method that allows for monitoring and / or control of various ingot growth parameters and / or provides a visual output of the parameters that is easily accessible to an operator and provides a simple visual overview of the ingot growth system.

[0005] This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and / or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art. Summary of the Invention

[0006] One aspect of the present disclosure relates to a method for growing a single crystal silicon ingot by the Czochralski method. A silicon melt is prepared in a crucible. A single crystal silicon ingot is drawn from the melt. A plurality of growth parameters for growing the single crystal silicon ingot are provided. A dynamic statechart including a visual representation of the growth parameters is provided.

[0007] Another aspect of the present disclosure relates to an ingot growth system for producing monocrystalline silicon ingots. The system includes a growth chamber and a crucible disposed within the growth chamber. The crucible is configured to hold a melt including molten silicon. The system includes an ingot pulling mechanism for withdrawing an ingot from the melt. The system includes a control unit having a processor and a memory. The memory stores instructions that, when executed by the processor, cause the processor to determine a plurality of growth parameters associated with growing the monocrystalline silicon ingot and provide a user with a dynamic statechart including a visual representation of the growth parameters.

[0008] Various refinements exist for the features described in connection with the above-described aspects of the present disclosure. The above-described aspects of the present disclosure may also include additional features. These refinements and additional features may exist individually or in any combination. For example, the various features described below in connection with any of the exemplary embodiments of the present disclosure may be included in any of the above-described aspects of the present disclosure, either alone or in any combination. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view of an exemplary ingot growth system. [Figure 2] FIG. 1 is a schematic diagram of a control system for controlling and / or monitoring the growth of an ingot. [Figure 3] FIG. 1 is a schematic diagram of a system for receiving measurements from one or more sensors of an ingot growth system. [Figure 4] FIG. 1 is a schematic diagram of a computing device for controlling an ingot growth system. [Figure 5] FIG. 1 is a schematic diagram of a control system for controlling and / or monitoring the growth of an ingot. [Figure 6] A dynamic statechart containing four sectors, each associated with an ingot growth parameter. [Figure 7] A dynamic statechart containing seven sectors, each associated with an ingot growth parameter.

[0010] Corresponding reference characters indicate corresponding parts throughout the drawings. DETAILED DESCRIPTION OF THE INVENTION

[0011] Articles of the present disclosure relate to methods and systems for growing single crystal silicon ingots. In exemplary methods, a dynamic statechart is provided that includes a visual representation of multiple growth parameters. The dynamic statechart may be described herein as being used in a continuous Czochralski process, where polysilicon is added to a crucible continuously or intermittently. The dynamic statechart may also be used in a batch Czochralski system.

[0012] An exemplary ingot growth system 5 for producing an ingot 60 by the continuous Czochralski process is shown in FIG. 1. The ingot growth system 5 includes a crucible assembly 10 having multiple weirs 20, 30, 40 or fluid barriers that separate the melt into different melt zones. In the illustrated embodiment, the crucible assembly 10 includes a first weir 20 (broadly, a fluid barrier) that defines an inner melt zone 22 of the silicon melt. The inner melt zone 22 is the growth region from which the single crystal silicon ingot 60 grows. A second weir 30 defines an intermediate melt zone 32 of the silicon melt. A third weir 40 defines an outer melt zone 42 of the silicon melt.

[0013] The feed pipe 46 supplies polycrystalline silicon, which may be granular, chunky, or a combination of granular and chunky, to the outer melt zone 42 at a rate sufficient to maintain a substantially constant melt rise level and volume during growth of the ingot 60. The first weir 20, second weir 30, and third weir 40 each have a generally annular shape and at least one opening defined therein for allowing the molten silicon to flow radially inward toward the growth region of the inner melt zone 22.

[0014] The crucible configuration shown in Figure 1 is exemplary and suitable for carrying out the process of the present disclosure. Other configurations suitable for continuous Czochralski may be used without departing from the scope of the present disclosure. For example, crucible assembly 10 may lack second weir 30 and / or may lack third weir 40.

[0015] Typically, the melt from which the ingot 60 is drawn is formed by loading polycrystalline silicon into a crucible to form an initial silicon charge. Typically, the initial charge is about 100 kilograms to about 200 kilograms of polycrystalline silicon, which may be granular, chunky, or a combination of granular and chunky. The mass of the initial charge depends on the desired crystal diameter and hot zone design. Because polycrystalline silicon is continuously fed during crystal growth, the initial charge does not reflect the crystal length. For example, if polycrystalline silicon is continuously fed and the chamber is sufficiently tall, the crystal length can be extended to 2000 mm, 3000 mm, or even 4000 mm.

[0016] Various polycrystalline silicon sources can be used, including, for example, granular polycrystalline silicon produced by the pyrolysis of silane or halosilane in a fluidized bed reactor, or polycrystalline silicon produced in a Siemens reactor. Once the polycrystalline silicon is added to a crucible to form a charge, the charge is heated to a temperature above the approximate melting temperature of silicon (e.g., about 1412°C) to melt the charge and thereby form a silicon melt containing molten silicon. The silicon melt has an initial volume of molten silicon and an initial melt rise level, with these parameters being determined by the size of the initial charge. In some embodiments, the crucible containing the silicon melt is heated to a temperature of at least about 1425°C, at least about 1450°C, or even at least about 1500°C.

[0017] A pulling mechanism 114 is provided within the system 5 for growing and pulling an ingot 60 from the melt within the inner melt zone 22. The pulling mechanism 114 includes a pulling cable 118, a seed holder or chuck 120 coupled to one end of the pulling cable 118, and a seed crystal 122 coupled to the seed holder or chuck 120 for initiating crystal growth. One end of the pulling cable 118 is connected to a pulley (not shown) or drum (not shown), or any other suitable type of lifting mechanism, such as a shaft, and the other end is connected to the chuck 120, which holds the seed crystal 122. During operation, the seed crystal 122 is lowered into contact with the melt within the inner melt zone 22. The pulling mechanism 114 operates to raise the seed crystal 122 along a pulling axis A, thereby pulling a single crystal ingot 60 from the melt.

[0018] As the charge liquefies to form a silicon melt containing molten silicon, the silicon seed crystal 122 descends and contacts the melt in the inner melt zone 22. The silicon seed crystal 122, with the silicon attached thereto, is then pulled out of the melt to form a neck 52, thereby forming a melt-solid interface near or at the surface of the melt. Generally, the initial pull rate to form the neck 52 is fast. In some embodiments, the silicon seed crystal 122 and neck 52 are pulled at a neck pull rate of at least about 1.0 mm / min, e.g., about 1.5 mm / min to about 6 mm / min, e.g., about 3 mm / min to about 5 mm / min. The neck 52 may be about 300 mm to about 700 mm in length, e.g., about 450 mm to about 550 mm in length. However, the length of the neck 52 may vary outside these ranges.

[0019] The pulling mechanism 114 can rotate the seed crystal 122 and the ingot 60 connected thereto. The crucible drive unit 44 can rotate the crucible assembly 10. In some embodiments, the silicon seed crystal 122 and the crucible assembly 10 rotate in opposite directions, i.e., counter-rotation. Counter-rotation induces convection in the silicon melt. Rotation of the crystal 122 is primarily used to provide a symmetrical temperature profile, suppress angular fluctuations of impurities, and control the crystal-melt interface shape. In some embodiments, the silicon seed crystal 122 rotates at a speed of about 5 rpm to about 30 rpm, or about 5 rpm to about 20 rpm, or about 8 rpm to about 20 rpm, or about 10 rpm to about 20 rpm. In some embodiments, the crucible assembly 10 rotates at a speed of about 0.5 rpm to about 10 rpm, or about 1 rpm to about 10 rpm, or about 4 rpm to about 10 rpm, or about 5 rpm to about 10 rpm. In some embodiments, the seed crystal 122 rotates at a faster rate than the crucible assembly 10. In some embodiments, the seed crystal 122 rotates at a rate that is at least 1 rpm faster than the rotational rate of the crucible assembly 10, such as at least about 3 rpm faster, or at least about 5 rpm faster.

[0020] After the neck 52 is formed, an outwardly expanding seed cone portion 54 adjacent the neck 52 is grown. Typically, the pull rate is slowed from the neck pull rate to a rate suitable for growing the outwardly expanding seed cone portion 54. For example, the seed cone pull rate during outwardly expanding seed cone growth may be about 0.5 mm / min to about 2.0 mm / min, e.g., about 1.0 mm / min. In some embodiments, the outwardly expanding seed cone 54 has a length of about 100 mm to about 400 mm, e.g., about 150 mm to about 250 mm. The length of the outwardly expanding seed cone 54 may vary outside these ranges. In some embodiments, the outwardly expanding seed cone 54 is grown to a terminal diameter of about 150 mm, at least about 150 mm, about 200 mm, at least about 200 mm, about 300 mm, at least about 300 mm, about 450 mm, or even at least about 450 mm. The terminal diameter of the outwardly extending seed cone 54 is generally equal to the diameter of the constant diameter of the body 56 of the single crystal silicon ingot 60 .

[0021] After the neck 52 and the outwardly extending seed cone 54 adjacent the neck 52 are formed, a constant diameter portion 56 or "body" is grown. The diameter of the body 56 may vary, and in some embodiments, the diameter may be about 150 mm, at least about 150 mm, about 200 mm, at least about 200 mm, about 300 mm, at least about 300 mm, about 450 mm, or even at least about 450 mm. The body 56 of the single crystal silicon ingot 60 is grown to a final length of at least about 1000 mm, e.g., at least 1400 mm, e.g., at least 1500 mm, or at least 2000 mm, or at least 2200 mm, e.g., 2200 mm, or at least about 3000 mm, or at least about 4000 mm.

[0022] While ingot 60 is withdrawn from the melt, silicon is added to outer melt zone 42 via pipe 46 or other channel to replenish the melt in ingot growth system 5. Solid polycrystalline silicon may be added from polycrystalline silicon supply system 66 and may be added continuously or intermittently to ingot growth system 5 to maintain the melt level. In general, polycrystalline silicon may be metered into ingot growth system 5 by any method available to those skilled in the art.

[0023] In some embodiments, dopants are also added to the melt during ingot growth. The dopants may be introduced from a dopant supply system 72. The dopants may be added as a gas or a solid, and may be added to the outer melt zone 42.

[0024] The system 5 may include a heat shield 116 disposed around the growing ingot 60 to allow the ingot 60 to release its latent heat of solidification and heat flux from the melt. The heat shield 116 may be at least partially conical in shape, sloping downward at an angle to form an annular opening in which the ingot 60 is placed. A flow of inert gas 64, such as argon, is typically provided along the length of the growing crystal. The ingot 60 is pulled from a growth chamber 78 that is sealed from the surrounding atmosphere.

[0025] Multiple independently controlled annular bottom heaters 70 may be arranged in a radial pattern below the crucible assembly 10. The annular bottom heaters 70 apply heat in a relatively controlled distribution across the entire base surface area of ​​the crucible assembly 10. The annular base heaters 70 may also be individually controlled planar resistive heating elements, as described in U.S. Pat. No. 7,635,414, which is incorporated herein by reference for all relevant and consistent purposes. The system 5 may include one or more side heaters 74 positioned radially outward of the crucible assembly 10 to control the temperature distribution during melting.

[0026] The ingot growth system 5 shown in FIG. 1 and described herein is exemplary, and generally, unless otherwise specified, any system in which crystalline ingots are prepared by the continuous Czochralski process can be used.

[0027] The system 5 for manufacturing silicon ingots 60 may include a control system 80 (FIG. 2) for controlling and / or monitoring ingot growth. The system 80 may include a control unit 82 that controls the ingot growth system 5 based on user input and sensors that detect one or more parameters related to crystal growth. A temperature sensor 84, such as a photovoltaic cell (i.e., a pyrometer), measures the temperature of the melt at its surface. A diameter transducer 86 measures the diameter of the ingot 60. A level sensor measures the level of the melt within the ingot growth system 5. A weight sensor 96 may be used to measure the weight of the crucible or the weight of the ingot. The control unit 82 may also be communicatively connected to a user interface 88 through which an operator can input one or more commands (e.g., setpoints) to control the ingot growth. The system 5 may include other inputs and / or sensors 92, including system power, current, vacuum, length, movement, position, velocity, distance, rotation, flow rate, pressure, volume, and / or weight.

[0028] The control unit 82 is used to adjust multiple process parameters, including, but not limited to, at least one of the crystal rotation speed, crucible rotation speed, ingot diameter, and melt temperature. The control unit 82 can control the heater power supply 123 to control the heat output of the bottom heater 70 (which can also be independently controlled) and / or the side heater 74. The control unit 82 is communicatively connected to the pulling mechanism 114 to control the pulling rate and / or rotation rate of the ingot 60, and is connected to the crucible drive unit 44 to adjust the rotation rate of the crucible assembly 10. The control unit 82 can also control the polycrystalline silicon supply system 66 to adjust the rate at which polycrystalline silicon is added to the melt. The control unit 82 can also be connected to the dopant supply system 72 to adjust the addition of dopants to the melt. The control unit 82 can also control one or more pumps and valves to control the growth chamber pressure and / or filter cleaning. The control unit 82 may control the system 5 using one or more algorithms (e.g., algorithms stored and / or executed by the control unit 82). Although one control unit 82 is shown, the system 80 may include two or more control units 82 for controlling one or more ingot growth parameters.

[0029] In various embodiments, the control unit 82 can include a processor that processes signals received from various sensors of the system 5, including, but not limited to, the temperature sensor 84, the diameter transducer 86, and the level sensor 90, and controls one or more devices of the system 5, including, but not limited to, the crucible drive unit 44, the pulling mechanism 114, the heater power supply 123, the vacuum pump 131, the gas flow regulator 129, the polycrystalline supply system 66, the dopant supply system 72, and any combination thereof.

[0030] The control unit 82 may be a computer system. A computer system as described herein refers to any known computing device and computer system. As described herein, all such computer systems include a processor and a memory. However, any processor in a computer system as referred to herein may also refer to one or more processors, and the processor may be in one computing device or multiple computing devices operating in parallel. Furthermore, any memory in a computing device as referred to herein may also refer to one or more memories, and the memory may be in one computing device or multiple computing devices operating in parallel.

[0031] As used herein, the term processor refers to a central processing unit, microprocessor, microcontroller, reduced instruction set circuit (RISC), application specific integrated circuit (ASIC), logic circuit, and any other circuit or processor capable of performing the functions described herein. The foregoing are examples only, and thus are not intended to limit in any way the definition and / or meaning of the term "processor."

[0032] As used herein, the term "database" may refer to a body of data, a relational database management system (RDBMS), or both. As used herein, a database may include any collection of data, including hierarchical databases, relational databases, flat-file databases, object-relational databases, object-oriented databases, and any other structured collection of records or data stored in a computer system. The above are merely examples and are therefore not intended to limit the definition and / or meaning of the term database. Examples of RDBMS include, but are not limited to, Oracle® Database, MySQL, IBM® DB2, Microsoft® SQL Server, Sybase®, and PostgreSQL. However, any database that enables the systems and methods described herein may be used. (Oracle is a registered trademark of Oracle Corporation, Redwood Shores, California. IBM is a registered trademark of International Business Machines Corporation, Armonk, New York. Microsoft is a registered trademark of Microsoft Corporation, Redmond, Washington. Sybase is a registered trademark of Sybase, Dublin, California.)

[0033] In one embodiment, a computer program for enabling the control unit 82 is provided, the program embodied on a computer-readable medium. In one example embodiment, the computer system runs on a single computer system without requiring connection to a server computer. In a further embodiment, the computer system runs in a Windows® environment (Windows is a registered trademark of Microsoft Corporation, Redmond, Washington). In yet another embodiment, the computer system runs on a mainframe environment and a UNIX® server environment (UNIX is a registered trademark of X / Open Company Limited, Reading, Berkshire, England). Alternatively, the computer system runs in any suitable operating system environment. The computer program is flexible and designed to operate in a variety of different environments without compromising primary functionality. In some embodiments, the computer system includes multiple components distributed across multiple computing devices. One or more components may be in the form of computer-executable instructions embodied in a computer-readable medium.

[0034] The computer systems and processes are not limited to the specific embodiments described herein. Furthermore, each computer system component and each process can be implemented separately and independently from other components and processes described herein. Each component and process may also be used in combination with other assembly packages and processes.

[0035] In one embodiment, the computer system may be configured as a server system. Figure 3 illustrates an example configuration of server system 301, which is used to receive measurements from one or more sensors, including, but not limited to, temperature sensor 84, diameter transducer 86, and level sensor 90, and any combination thereof, as described herein and shown in the embodiment of Figures 1-2, and which is also used to control one or more devices of system 5, including, but not limited to, crucible drive unit 44, pulling mechanism 114, heater power supply 123, supply system 66, vacuum pump 131, gas flow regulator 129, dopant supply system 72, and any combination thereof. Referring again to Figure 3, server system 301 may also include, but is not limited to, a database server. In this exemplary embodiment, server system 301 performs all steps used to control one or more devices of system 80, as described herein.

[0036] The server system 301 includes a processor 305 for executing instructions. The instructions may be stored, for example, in memory 310. The processor 305 may include one or more processing units (e.g., in a multi-core configuration) for executing the instructions. The instructions may be executed within a variety of different operating systems on the server system 301, such as, for example, UNIX, LINUX, Microsoft Windows, etc. It should also be understood that various instructions may be executed during initialization at the start of a computer-based method. Some operations may be required to perform one or more processes described herein, while other operations may be more general and / or specific to a particular programming language (e.g., C, C#, C++, Java, or any other suitable programming language).

[0037] The processor 305 is operably coupled to a communication interface 315 such that the server system 301 can communicate with a remote device, such as a user system or another server system 301. For example, the communication interface 315 can receive requests (e.g., requests to receive sensor inputs and provide an interactive user interface for controlling one or more devices of the system 80 from a client system over the Internet).

[0038] The processor 305 may also be operatively coupled to the storage device 134. The storage device 134 is any computer-operated hardware suitable for storing and / or retrieving data. In some embodiments, the storage device 134 is integrated into the server system 301. For example, the server system 301 may include one or more hard disk drives as the storage device 134. In other embodiments, the storage device 134 is external to the server system 301 and may be accessed by multiple server systems 301. For example, the storage device 134 may include multiple storage units, such as hard disks or solid-state disks in a redundant array of independent disks (RAID) configuration. The storage device 134 may include a storage area network (SAN) and / or a network-attached storage (NAS) system.

[0039] In some embodiments, the processor 305 is operably coupled to the storage device 134 via a storage interface 320. The storage interface 320 is any component capable of providing the processor 305 with access to the storage device 134. The storage interface 320 may include, for example, an Advanced Technology Attachment (ATA) adapter, a Serial ATA (SATA) adapter, a Small Computer System Interface (SCSI) adapter, a RAID controller, a SAN adapter, a network adapter, and / or any component that provides the processor 305 with access to the storage device 134.

[0040] The memory 310 may include, but is not limited to, random access memory (RAM), such as dynamic RAM (DRAM) or static RAM (SRAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), and non-volatile RAM (NVRAM). The above memory types are merely examples and thus do not limit the types of memory that may be used for storage of computer programs.

[0041] In another embodiment, the computer system may be provided in the form of a computing device, such as computing device 402 (shown in FIG. 4). Computing device 402 includes a processor 404 for executing instructions. In some embodiments, executable instructions are stored in memory 406. Processor 404 may include one or more processing units (e.g., in a multi-core configuration). Memory 406 is any device that allows information, such as executable instructions and / or other data, to be stored and retrieved. Memory 406 may include one or more computer-readable media.

[0042] In another embodiment, the memory included in the computing device of the control unit 143 may include multiple modules. Each module may include instructions configured to execute using at least one processor. The instructions included in the multiple modules, when executed by one or more processors of the computing device, may implement at least a portion of a method for simultaneously regulating multiple process parameters, as described herein. Non-limiting examples of modules stored in the memory of the computing device include a first module that receives measurements from one or more sensors and a second module that controls one or more devices of the system 80.

[0043] Computing device 402 also includes one media output component 408 for presenting information to user 400. Media output component 408 is any component capable of communicating information to user 400. In some embodiments, media output component 408 includes an output adapter, such as a video adapter and / or an audio adapter. The output adapter is operably coupled to processor 404 and is further configured to be operably coupled to an output device, such as a display device (e.g., a liquid crystal display (LCD), an organic light emitting diode (OLED) display, a cathode ray tube (CRT), or an “electronic ink” display) or an audio output device (e.g., speakers or headphones).

[0044] In some embodiments, the client computing device 402 includes an input device 410 for receiving input from the user 400. The input device 410 may include, for example, a keyboard, a pointing device, a mouse, a stylus, a touch-sensitive panel (e.g., a touchpad or touchscreen), a camera, a gyroscope, an accelerometer, a position detector, and / or an audio input device. A single component, such as a touchscreen, may function as both an output device for the media output component 408 and as the input device 410.

[0045] The computing device 402 may also include a communication interface 412, which is configured to communicatively couple to a remote device, such as the server system 301 or a web server. The communication interface 412 may include, for example, a wired or wireless network adapter or a wireless data transceiver for use with a cellular network (e.g., Global System for Mobile Communications (GSM), 3G, 4G, 5G, or Bluetooth) or other mobile data network (e.g., Worldwide Interoperability for Microwave Access (WIMAX)).

[0046] Stored in memory 406 are computer-readable instructions for, for example, providing a user interface to user 400 via media output component 408 and, optionally, receiving and processing input from input device 410. The user interface may include, among other things, a web browser and an application. The web browser allows user 400 to view and interact with media and other information typically embedded on a web page or website from a web server. The application allows user 400 to interact with server applications. The user interface facilitates the display of information related to the manufacturing process for low-oxygen content monocrystalline silicon ingots via one or both of the web browser and the application.

[0047] 5, the control unit 82 includes a processor 404 and a memory 406. The memory 406 stores instructions that, when executed by the processor 404, cause the processor 404 to determine a plurality of growth parameters associated with growing the single crystal silicon ingot 60. The processor 404 can also provide a user with a dynamic statechart 504 (FIG. 6) that includes a visual representation of the growth parameters, as described below.

[0048] In some embodiments, the control system 80 ( FIG. 2 ) is configured to provide a user with a plurality of growth parameters related to the growth of the monocrystalline silicon ingot 60. For example, as shown in FIG. 5 , the control system 80 can obtain input from a sensor system 94, which may include one or more of the sensors shown in FIG. 2 . The input device 410 is also capable of communicating with the control unit 82. The control unit 82 is communicatively connected to a user interface 88, such as via a media output 408, as shown in FIG. 5 . The user interface 88 includes a plurality of growth parameters related to the growth of the monocrystalline silicon ingot. The user interface 88 can include a visual medium (e.g., a screen that displays information and / or is capable of receiving information from a user). The user interface can include a program, an application, a web browser, or the like.

[0049] In some embodiments, the control system 80 for modifying, altering, or controlling the ingot growth system 5 includes a control unit 82 that is different from the control unit used to generate the dynamic statecharts 88 described below. In other embodiments, the control system 80 for modifying, altering, or controlling the ingot growth system 5 is part of the same system that generates the user interface 88, and the user interface 88 includes the dynamic statecharts (i.e., the same control unit 82 is used). The user interface 88 can include a development environment such as Microsoft Visual Studio, Oracle Java, Siemens Wincc, or Wonderware Intouch. The development environment is used to create the interface features. A program (e.g., a runtime application) runs on a machine (e.g., a computer or server) to provide the user interface 88.

[0050] In some embodiments, the user interface 88 includes or otherwise displays a user-visible dynamic statechart. For example, the dynamic statechart may provide a visual (e.g., graphical) representation of multiple growth parameters changing in response to changes in growth parameters. An exemplary dynamic statechart 504 is shown in FIG. 6. The exemplary dynamic statechart 504 is a circular statechart divided into sectors 518, 528, 538, and 548. Each sector is associated with a different growth parameter. While four sectors are shown in FIG. 6, the statechart 504 may include more or fewer sectors (e.g., two or more sectors, three or more, four or more, five or more, six or more, eight or more, or ten or more sectors) associated with ingot growth parameters. Suitable ingot growth parameters that may be associated with a sector of the dynamic statechart 504 include, for example, but are not limited to, ingot target length, ingot diameter, seed lift rate, distance between the heat shield and the melt surface (i.e., heat shield position), polysilicon feed rate to the crucible (as in a continuous Czochralski system), dopant feed rate to the crucible, ingot puller pressure, ingot growth rate (e.g., radial crown growth rate), etc.

[0051] In some embodiments, the circular statechart can have one or more dynamic features. For example, one or more sectors 518, 528, 538, 548 can change size in response to changes in the value of a corresponding ingot growth parameter. Each sector 518, 528, 538, 548 is located at the center C of the circular statechart. 504 From the outer edge E of sectors 518, 528, 538, and 548 518 , E 528 , E 538 , E 548 Radius R extends to 518 , R 528 , R 538 , R 548 The radius R 518 , R 528 , R 538 , R548 changes with changes in the growth parameter value.

[0052] One or more of the sectors 518, 528, 538, 548 of the circular statechart 504 can include a minimum growth parameter visual 520 and / or a maximum growth parameter visual 525. In the illustrated embodiment, the minimum growth parameter visual 520 is a first arc, and the maximum growth parameter visual 525 is a second arc positioned radially outward from the first arc. The first and second arcs 520, 525 define a circular sector 530. The circular sector 530 can represent an allowable range for the respective growth parameter.

[0053] In the illustrated embodiment, the dynamic statechart 504 also includes a target growth parameter visual 540. The target growth parameter visual 540 may be associated with each sector and represent a target value for the respective growth parameter. The target growth parameter visual 540 may be a third arc, as shown in FIG. 6.

[0054] The ingot growth parameters may be normalized across the radius of the circular statechart 504. For example, the minimum, maximum, and target growth parameter arcs of each sector 518, 528, 538, 548 each lie at the same radial position (i.e., the circular statechart center C) such that the minimum arc 520 forms a circle, the target growth parameter arc 540 forms a circle, and the maximum arc 525 forms a circle. 504 In other embodiments, the arcs of sectors 518, 528, 538, 548 are at different radial locations.

[0055] In some embodiments, each sector 518, 528, 538, 548 changes color and / or darkness in response to changes in the respective ingot growth parameter value. For example, sectors that are at or below the target value (indicated by the target arc 540) may be a first color (indicated by a first stipple pattern in the first, second, and third sectors 518, 528, 538), and sectors that are above the target value may be a second color (indicated by a second stipple pattern in the fourth sector 548). In some embodiments, the color or color darkness may vary within a sector. For example, the color within a sector may be a color that is different from the center C 504 From outer edge E 518 , E 528 , E 538 , E 548 , the sector may gradually become darker (e.g., the sector may be darkest at the maximum target growth parameter visual 525).

[0056] The circular statechart 504 may include one or more lobes 522, 524, 526, 532 for monitoring one or more ingot growth parameters. The lobes 522, 524, 526, 532 may be configured to move relative to the circular chart center C based on changes in the ingot growth parameters. 504 Alternatively, the lobes 522, 524, 526, 532 may change color or size in response to changes in ingot growth parameters.

[0057] Statechart 504 is an exemplary statechart and, unless otherwise stated, other statecharts may be used that provide the user with information regarding two or more ingot growth parameters.

[0058] One or more growth parameters monitored in statechart 504 may be measured directly in ingot growth system 5 (FIG. 1). For example, the parameters may be measured by sensors in sensor system 94 (FIG. 5). Exemplary sensors include temperature sensor 84, diameter transducer 86, and level sensor 90, as well as weight sensor 96. Instead of being measured directly, one or more growth parameters may be generated by an algorithm, such as an algorithm stored in control unit 82.

[0059] Compared to conventional methods and systems for growing monocrystalline silicon ingots using the continuous Czochralski process, the methods of the disclosed embodiments have several advantages. By providing a dynamic statechart, an operator can quickly access several ingot growth parameters, which allows for quicker changes to the ingot growth system compared to systems that access parameters in multiple places (e.g., multiple pages). In embodiments where the dynamic statechart is a dynamic circular map divided into sectors, each sector can be associated with an ingot growth parameter that provides the operator with an immediate overview of the system's performance. The ingot growth parameters may be normalized in the dynamic statechart, which allows parameters to have common growth visuals (e.g., minimum growth visual, maximum growth visual, and / or target growth visual, which may be individually represented by arcs in the dynamic statechart). The dynamic statechart allows the operator to quickly access system parameters without overwhelming the operator with information. [Example]

[0060] The processes of the present disclosure are further illustrated by the following examples, which should not be construed in a limiting sense.

[0061] Example 1: Dynamic statechart with four ingot growth parameters A dynamic statechart developed to control ingot growth in a continuous Czochralski ingot growth system is shown in FIG. 6. The dynamic statechart is a dynamic circular chart with four sectors 518, 528, 538, and 548 (separated by dashed lines). The first and third sectors 518 and 538 monitor "Value D," which represents other ingot growth parameters (e.g., weight, temperature, diameter, level, system pressure, etc.). The second sector 528 monitors seed drift (i.e., the rate at which the seed crystal 122 grows in the ingot puller). The fourth sector 548 monitors the ingot growth rate. As shown in the dynamic statechart of FIG. 6, "Value D" is at or near the target growth value, indicated by the central arc 540. The seed drift is below the target value, and the growth rate is above the target value. The dynamic statechart allows for the monitoring and control of multiple growth parameters in a single visual.

[0062] Example 2: Dynamic Statechart with Seven Ingot Growth Parameters A dynamic statechart 604 illustrating seven ingot growth parameters is shown in Figure 7. The dynamic statechart is a dynamic circular statechart including a first sector 618 that monitors heat shield position, a second sector 628 that monitors seed drift rate, a third sector 638 that monitors ingot diameter, a fourth sector 648 that monitors ingot target length, a fifth sector 658 that monitors ingot growth system pressure, a sixth sector 668 that monitors dopant feed rate to the melt, and a seventh sector 678 that monitors the rate at which silicon is added to the melt. The monitored parameters may be measured directly or may be the output of one or more algorithms. The growth parameters are determined by the fact that the target growth visual (i.e., arc) for each sector is centered on the circular map center C. 604 are normalized to be the same distance from

[0063] As used herein, the terms "about," "substantially," "essentially," and "approximately," when used in conjunction with a range of dimensions, concentrations, temperatures, or other physical or chemical properties or characteristics, are meant to encompass variations that may exist at the upper and / or lower limits of the range of the property or characteristic, including variations that result, for example, from rounding, measurement methodology, or other statistical variations.

[0064] When introducing elements of this disclosure or embodiments thereof, the articles "a," "an," "the," and "said" are intended to mean that there are one or more elements. The terms "comprising," "including," "containing," and "having" are intended to be inclusive and mean that additional elements may be present other than the listed elements. The use of language indicating a particular orientation (e.g., "top," "bottom," "side," etc.) is a convenient description and does not require a particular orientation of the described items.

[0065] Since various changes can be made in the above-described structures and methods without departing from the scope of the present disclosure, it is intended that all matter contained in the above description and shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense.

Claims

1. 1. A method for growing a single crystal silicon ingot in a Czochralski process, comprising: preparing a melt of silicon in a crucible; withdrawing a single crystal silicon ingot from the melt; providing a plurality of growth parameters associated with growing the single crystal silicon ingot; providing a dynamic statechart including a visual representation of the growth parameters; A method comprising:

2. 10. The method of claim 1, further comprising adding polycrystalline silicon to the melt while the silicon ingot is being withdrawn from the melt to replenish the silicon in the crucible.

3. The method of claim 1 or 2, wherein the dynamic statechart is a circular statechart divided into sectors, each sector being associated with a growth parameter.

4. 4. The method of claim 3, wherein the circular statechart has a center and each sector has an outer edge and a radius extending from the center of the circular statechart to the outer edge, the radius varying in response to changes in the growth parameter value.

5. The method of any one of claims 1 to 4, wherein the dynamic statechart includes minimum and maximum growth parameter visuals associated with each growth parameter.

6. 6. The method of claim 5, wherein the dynamic statechart is a circular statechart, the minimum growth parameter visual is a first arc, and the maximum growth parameter visual is a second arc positioned radially outward from the first arc, the first arc and the second arc defining a circular sector representing an allowable range for the growth parameter.

7. The method of claim 6 , wherein the dynamic statechart includes a target growth parameter visual, the target growth parameter visual being a third arc, the third arc being positioned between the first arc and the second arc.

8. the first arcs of each sector are the same distance from the center of the circular statechart such that the first arcs join to form a first circle; the second arcs of each sector are equidistant from the center of the circular statechart such that the second arcs join to form a second circle concentric with the first circle; 8. The method according to claim 6 or 7.

9. 9. The method of any one of claims 1 to 8, wherein the growth parameters are selected from the group consisting of ingot target length, ingot diameter, seed lift rate, heat shield position, polysilicon feed rate, dopant feed rate, ingot puller pressure, and ingot growth rate.

10. The method of any one of claims 1 to 9, further comprising changing a color of the visual representation based on a change in one or more growth parameter values.

11. The plurality of growth parameters are: by measuring the growth parameters in an ingot growth system, the crucible being located in a growth chamber of the ingot growth system; or by generating the growth parameters from an algorithm, The method according to any one of claims 1 to 10.

12. 1. An ingot growth system for producing a single crystal silicon ingot, the system comprising: a growth chamber; a crucible disposed within the growth chamber configured to hold a melt comprising molten silicon; an ingot pulling mechanism for pulling an ingot from the melt; A control unit comprising a processor and a memory, the memory storing instructions that, when executed by the processor, cause the processor to: determining a plurality of growth parameters for growing the single crystal silicon ingot; a control unit for providing a user with a dynamic statechart including a visual representation of the growth parameters; An ingot growing system including:

13. 13. The ingot growing system of claim 12, further comprising adding polycrystalline silicon to the melt while drawing a silicon ingot from the melt to replenish silicon in the crucible.

14. 14. The ingot growth system of claim 13, wherein the dynamic statechart is a circular statechart divided into sectors, each sector associated with a growth parameter.

15. 15. The ingot growth system of claim 14, wherein the circular statechart has a center and each sector has an outer edge and a radius extending from the center of the circular statechart to the outer edge, the radius varying in response to changes in the growth parameter values.

16. 16. The ingot growth system of any one of claims 12 to 15, wherein the dynamic statechart includes minimum and maximum growth parameter visuals associated with each growth parameter.

17. 17. The ingot growth system of claim 16, wherein the dynamic statechart is a circular statechart, the minimum growth parameter visual is a first arc, and the maximum growth parameter visual is a second arc positioned radially outward from the first arc, the first arc and the second arc defining an annular sector representing an allowable range for the growth parameter.

18. 18. The ingot growth system of claim 17, wherein the dynamic statechart includes a target growth parameter visual, the target growth parameter visual being a third arc, the third arc being positioned between the first arc and the second arc.

19. the first arcs of each sector are the same distance from the center of the circular statechart such that the first arcs join to form a first circle; 19. An ingot growth system as claimed in claim 17 or 18, wherein the second arcs of each sector are the same distance from the centre of the circular statechart such that the second arcs join to form a second circle concentric with the first circle.

20. 20. The ingot growth system of any one of claims 12 to 19, wherein the growth parameters are selected from the group consisting of ingot target length, ingot diameter, seed lift rate, heat shield position, polysilicon feed rate, dopant feed rate, ingot puller pressure, and ingot growth rate.

21. 21. An ingot growth system as described in any one of claims 12 to 20, wherein the memory stores instructions that, when executed by the processor, cause the processor to change the color of the visual representation based on changes in growth parameter values.

22. 22. An ingot growth system according to any one of claims 12 to 21, wherein the system comprises a sensor system for measuring one or more ingot growth parameters, the sensor system being communicatively connected to the control unit.

23. 22. An ingot growth system according to any one of claims 12 to 21, wherein the system is configured to generate one or more ingot growth parameters from an algorithm.

Images