Single crystal furnace observation window and single crystal furnace

Abstract

The utility model provides a single crystal furnace observation window and a single crystal furnace. The single crystal furnace observation window comprises window body glass, standby glass and a driving assembly, the window glass is arranged on the outer wall of the single crystal furnace; the standby glass is arranged in the single crystal furnace, and the standby glass is attached to the inner surface of the window glass and covers the inner surface of the window glass; the driving assembly is connected with the edge of the standby glass, and when pollutants are attached to the inner surface of the standby glass, the standby glass is driven to rotate along the rotating axis so as to relieve covering of the inner surface of the window body glass. According to the configuration, the standby glass is arranged on the inner side of the window glass, when a crystal bar located in monocrystalline silicon generates oxide in the growth process, the oxide can be attached to the inner surface of the standby glass, at the moment, the standby glass is driven by the driving assembly to rotate, and covering on the window glass is relieved; and an operator can still observe the condition in the single crystal furnace through the window glass, so that the smooth growth of a crystal bar is ensured, and the product yield is improved.

Description

Technical Field

[0001] The utility model relates to the field of semiconductor manufacturing, in particular to a single crystal furnace observation window and a single crystal furnace. Background Art

[0002] A single crystal furnace is a device that uses a graphite heater to melt polycrystalline materials such as polysilicon in an inert gas environment and grows single crystals without dislocation using the Czochralski method. During the single crystal growth process, it is necessary to monitor parameters such as the diameter of the crystal rod in the furnace through the observation window on the furnace cover to control the stable growth of the crystal. However, once the exhaust is not smooth or other abnormal conditions occur, the oxides in the furnace will adhere to the inner surface of the observation window glass, seriously affecting the operator's monitoring and causing the crystal rod to fail to grow smoothly.

[0003] In the prior art, a blade assembly can be set on the furnace cover of the single crystal furnace, and the blades can be rotated to generate a downward moving airflow, so that the running trajectory of the volatiles is deviated, and the volatiles are prevented from adhering to and accumulating on the observation window. However, in actual use, due to the negative pressure in the furnace, the overall airflow running direction is originally downward, the airflow movement trajectory is relatively complex, and the airflow intensity generated by the rotation of the blades is relatively weak, so it is difficult to inhibit the accumulation of oxides, and the inhibition effect is poor.

[0004] Based on this, how to effectively reduce the oxide adhesion on the observation window and affect the operator's observation of the situation inside the single crystal furnace has become a technical problem that technical personnel in this field need to solve. Utility Model Content

[0005] The utility model aims to provide a single crystal furnace observation window and a single crystal furnace, so as to solve the problem that oxides adhere to the observation window, causing the operator to be unable to monitor the situation in the single crystal furnace.

[0006] In order to achieve the above-mentioned object, the utility model provides a single crystal furnace observation window, comprising: window glass, spare glass and a driving component;

[0007] The window glass is arranged on the outer wall of the single crystal furnace and is used to observe the internal conditions of the single crystal furnace;

[0008] The spare glass is arranged inside the single crystal furnace and parallel to the window glass. The spare glass is in contact with the inner surface of the window glass and covers the inner surface of the window glass.

[0009] The driving assembly is rotatable along a rotation axis and is connected to the edge of the spare glass. When contaminants adhere to the inner surface of the spare glass, the driving assembly drives the spare glass to rotate along the rotation axis to release the covering of the inner surface of the window glass.

[0010] Optionally, the size of the window glass matches the size of the spare glass, and the window glass and the spare glass are coaxially arranged.

[0011] Optionally, the single crystal furnace observation window includes a plurality of spare glasses, which are arranged in sequence along the rotation axis, and two adjacent spare glasses are bonded to each other, and the spare glass farther from the window glass covers the inner surface of the spare glass closer to the window glass.

[0012] Optionally, when contaminants adhere to the inner surface of the spare glass that is farthest from the window glass along the rotation axis, the connected driving assembly drives the spare glass to rotate along the rotation axis to release the covering of the inner surface of the spare glass that is in contact with it.

[0013] Optionally, the single crystal furnace observation window includes a plurality of the driving components, and the driving components are connected to the edges of the spare glasses in a one-to-one correspondence, and the driving components respectively drive the connected spare glasses to rotate.

[0014] Optionally, the driving assembly includes a driving member and a connecting rod, wherein the connecting rod extends along the rotation axis and is connected to the edge of the spare glass, and the driving member is arranged on a side of the connecting rod away from the spare glass, for driving the connecting rod to rotate along the rotation axis.

[0015] Optionally, there are multiple connecting rods, and the multiple connecting rods are sequentially sleeved along the radial direction of the connecting rods.

[0016] Optionally, the thickness of the window glass on the rotation axis is greater than the thickness of the spare glass on the rotation axis.

[0017] Optionally, the rotation axis is perpendicular to the plane where the spare glass is located.

[0018] In order to achieve the above object, the utility model also provides a single crystal furnace, comprising: a furnace body, a furnace cover and the above-mentioned single crystal furnace observation window;

[0019] The furnace body is connected to the furnace cover to form the outer wall of the single crystal furnace, and the single crystal furnace observation window is arranged on the furnace cover.

[0020] Compared with the existing single crystal furnace, the single crystal furnace observation window and the single crystal furnace provided by the present application have the following advantages:

[0021] The single crystal furnace observation window provided in the present application is achieved by arranging spare glass on the inner side of the window glass, and the spare glass is in contact with the window glass, and the spare glass covers the inner surface of the window glass. Therefore, when the crystal rod located in the single crystal silicon produces oxide during the growth process, it will preferentially adhere to the inner surface of the spare glass. At this time, the spare glass is driven to rotate by the driving component, and the covering of the window glass is released, so that the operator can still observe the situation in the single crystal furnace through the window glass to ensure the smooth growth of the crystal rod, thereby improving the product yield; at the same time, considering that oxides will only appear in large quantities under unexpected circumstances, multiple spare glasses can be configured to ensure that the window glass will not be contaminated by oxides within a growth cycle, thereby reducing the frequency of shutdown maintenance and improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of the structure of a single crystal furnace observation window provided in an embodiment of the utility model;

[0023] Figure 2 A schematic diagram of a single crystal silicon observation window provided in an embodiment of the utility model being arranged on a single crystal furnace;

[0024] Figure 3 This is a schematic structural diagram of a single crystal furnace provided in an embodiment of the utility model.

[0025] The description of each reference numeral is as follows:

[0026] 1-Window glass; 2-Spare glass;

[0027] 3-driving assembly; 31-connecting rod; 32-driving member;

[0028] 4-furnace body; 5-furnace cover;

[0029] A - Axis of rotation. DETAILED DESCRIPTION

[0030] In order to make the purpose, advantages and features of the utility model clearer, the utility model is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the utility model. In addition, the structure shown in the drawings is often a part of the actual structure. In particular, the emphasis of each drawing is different, and sometimes different scales are used.

[0031] As used in this specification, the singular forms "a", "an" and "the" include plural objects, the term "or" is generally used to include the meaning of "and / or", the term "several" is generally used to include the meaning of "at least one", and the term "at least two" is generally used to include the meaning of "two or more". In addition, the terms "first", "second" and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second" and "third" may explicitly or implicitly include one or at least two of the features, "one end" and "the other end" and "the proximal end" and "the distal end" generally refer to two corresponding parts, which include not only the endpoints, and the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral body; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. In addition, as used in this specification, an element disposed on another element generally only indicates that there is a connection, coupling, cooperation or transmission relationship between the two elements, and the connection, coupling, cooperation or transmission between the two elements may be direct or indirect through an intermediate element, and it cannot be understood as indicating or implying the spatial position relationship between the two elements, that is, one element may be in any orientation such as inside, outside, above, below or on one side of another element, unless the content clearly indicates otherwise. The terms "upper", "lower", "top" and "bottom" are generally relative position relationships arranged in the direction of gravity; the terms "vertical, vertical direction" generally refer to the direction of gravity, which is generally perpendicular to the ground, and "horizontal, horizontal plane direction" generally refers to the direction parallel to the ground; for ordinary technicians in this field, the specific meanings of the above terms in this specification can be understood according to specific circumstances.

[0032] The utility model aims to provide a single crystal furnace observation window and a single crystal furnace, so as to solve the problem that oxides adhere to the observation window, causing the operator to be unable to monitor the situation in the single crystal furnace.

[0033] As can be understood by those skilled in the art, a vertical pull type single crystal silicon growth furnace is a device for efficiently preparing silicon single crystals. The basic process of single crystal production is usually to put polycrystalline silicon raw materials into a single crystal furnace, heat and melt, and gradually perform necking growth, shoulder growth, equal diameter growth and tail growth, and then open the furnace to take out the materials. The basic structure of a single crystal furnace is usually composed of an upper furnace chamber, a lower furnace chamber, a furnace cover, an isolation valve chamber, an observation window, a crystal lifting and rotating mechanism, a crucible lifting and rotating mechanism, a control cabinet and a base, and is supplemented by a lifting head, a transmission device and other auxiliary equipment to jointly realize the transformation from polycrystalline silicon raw materials to single crystal rods. During the production process, the operator needs to observe the crystal growth in the single crystal furnace through the observation window. Once an accident occurs, a large amount of silicon monoxide (SiO) will be generated during the crystal growth process and attached to the observation window, making it impossible for the operator to observe the situation in the furnace, thereby failing to ensure the normal growth of the crystal, thereby affecting the product yield. Based on this, the present application provides a single crystal furnace observation window and a single crystal furnace. By adding spare glass to the inner side of the window glass, when contaminants (SiO) appear, they can be preferentially attached to the spare glass. At this time, the spare glass is driven to rotate by the driving component to ensure that the window glass is always kept clean, and the operator can observe the situation in the furnace normally, thereby improving the product yield. It should be noted that this embodiment only takes the single crystal furnace as an example, which does not mean that the technical solution in this embodiment can only be used in the single crystal silicon production process. Those skilled in the art can use it in other processes to ensure that the operator can monitor the production process in real time, and this embodiment does not limit this.

[0034] Please refer to Figure 1 to Figure 2 The utility model provides a single crystal furnace observation window, comprising: a window glass 1, a spare glass 2 and a driving assembly 3; the window glass 1 is arranged on the outer wall of the single crystal furnace, and is used to observe the internal situation of the single crystal furnace; the spare glass 2 is arranged inside the single crystal furnace, and is arranged parallel to the window glass 1, and the spare glass 2 is in contact with the inner surface of the window glass 1 and covers the inner surface of the window glass 1; the driving assembly 3 can rotate along the rotation axis A and is connected to the edge of the spare glass 2, and when contaminants are attached to the inner surface of the spare glass 2, the driving assembly 3 drives the spare glass 2 to rotate along the rotation axis A to release the coverage of the inner surface of the window glass 1. It should be noted that the spare glass 2 covering the inner surface of the window glass 1 should be understood as the spare glass 2 completely covering the inner surface of the window glass 1; releasing the coverage of the inner surface of the window glass 1 should be understood as the spare glass 2 rotating to a position where the inner surface of the window glass 1 is completely exposed, that is, the spare glass 2 and the window glass 1 do not overlap in the extension direction of the rotation axis A. In this embodiment, since the single crystal furnace is in a negative pressure state during the crystal growth process, the temperature of the melt field in the furnace reaches above 1500°C. In order to ensure safety, the thickness of the window glass 1 (in this embodiment, the length of the window glass 1 in the extending direction of the rotation axis A) is generally above 15 mm. Figure 1 and Figure 2 In the illustrated example, the cross section of the window glass 1 is circular. In other embodiments, the cross section of the window glass 1 may also be rectangular, trapezoidal or other irregular shapes. This embodiment does not limit this. The window glass 1 may be connected to the outer wall of the single crystal furnace through a window frame. The window glass 1 is embedded in the window frame. The window frame is connected to the outer wall of the single crystal furnace. The size and shape of the window frame are adapted to the window glass 1. At the same time, the spare glass 2 is arranged on the inner side of the window glass 1, and is fitted with the window glass 1 and covers the inner surface of the window glass 1, so that the generated pollutants (SiO) are preferentially attached to the spare glass 2 without affecting the cleanliness of the window glass 1. Therefore, the thickness of the spare glass 2 can be relatively thin, and the number of spare glasses 2 is not limited. It should be noted that oxides are not generated during the normal growth of the crystal. Only in the case of unexpected failures such as leakage of the furnace body 4, oxides will be generated in large quantities and contaminate the window glass 1. Considering the cost and installation difficulty, the spare glass 2 is preferably set to three to ensure that the window glass 1 is not affected by pollutants during the entire crystal growth process. Figure 1 In the figure, the spare glass 2 and the spare glass 2, and the spare glass 2 and the window glass 1 are arranged at intervals, which is only for illustration. In actual use, the spare glass 2 and the spare glass 2 and the window glass 1 should be attached to each other (such as Figure 2 shown).

[0035] In such a configuration, by arranging a spare glass 2 on the inner side of the window glass 1, and the spare glass 2 is in contact with the window glass 1, the spare glass 2 covers the inner surface of the window glass 1. Therefore, when the crystal rod in the single crystal silicon produces oxides during the growth process, it will preferentially adhere to the inner surface of the spare glass 2. At this time, the spare glass 2 is driven to rotate by the driving component 3, and the covering of the window glass 1 is released, so that the operator can still observe the situation in the single crystal furnace through the window glass 1 to ensure the smooth growth of the crystal rod, thereby improving the product yield. At the same time, considering that oxides will only appear in large quantities under unexpected circumstances, multiple spare glasses 2 can be configured to ensure that the window glass 1 will not be contaminated by oxides within a growth cycle, thereby reducing the frequency of shutdown maintenance and improving production efficiency.

[0036] As an optional embodiment, the size of the window glass 1 matches the size of the spare glass 2, and the window glass 1 and the spare glass 2 are coaxially arranged. Figure 1 and Figure 2In the illustrated example, the window glass 1 and the spare glass 2 have the same size, and the only difference between the two is the thickness. The rest of the materials and configurations are the same. Both materials can be quartz glass. The window glass 1 and the spare glass 2 of the same size can reduce production costs, and the coaxial arrangement of the two can also reduce the difficulty of installation. In other embodiments, the size of the spare glass 2 can also be larger than the size of the window glass 1, and the spare glass 2 and the window glass 1 can also be arranged non-coaxially, as long as the spare glass 2 can completely cover the inner surface of the window glass 1.

[0037] Please refer to Figure 2 The single crystal furnace observation window includes a plurality of spare glasses 2, which are arranged in sequence along the rotation axis A. Two adjacent spare glasses 2 are bonded to each other, and the spare glass 2 far from the window glass 1 covers the inner surface of the spare glass 2 near the window glass 1. Furthermore, when contaminants adhere to the inner surface of the spare glass 2 farthest from the window glass 1 along the rotation axis A, the connected driving assembly 3 drives the spare glass 2 to rotate along the rotation axis A to release the covering of the inner surface of the bonded spare glass 2. Figure 2 In the illustrated example, two spare glasses 2 are provided on the observation window of the single crystal furnace, and the two spare glasses 2 are arranged in sequence along the rotation axis A, and the two adjacent spare glasses 2 are in contact with each other, so that when oxides are generated, they will preferentially adhere to the spare glass 2 farthest from the window glass 1. At this time, the spare glass 2 is driven to rotate by the driving component 3, so that the operator can still observe the crystal growth in the furnace through the window glass 1 and the remaining spare glasses 2. In other embodiments, the observation window of the single crystal furnace can also be provided with three or more spare glasses 2. Those skilled in the art can select a suitable number of spare glasses 2 based on the probability of unexpected situations in the single crystal furnace, so as to ensure that the operator can monitor the situation in the furnace in real time through the window glass 1 within a production cycle.

[0038] In an optional embodiment, the single crystal furnace observation window includes a plurality of driving components 3, and the driving components 3 are connected to the edges of the spare glass 2 in a one-to-one correspondence, and the driving components 3 drive the connected spare glass 2 to rotate. Further, the driving component 3 includes a driving member 32 and a connecting rod 31, and the connecting rod 31 extends along the rotation axis A and is connected to the edge of the spare glass 2. The driving member 32 is arranged on the side of the connecting rod 31 away from the spare glass 2, and is used to drive the connecting rod 31 to rotate along the rotation axis A. It should be noted that in this embodiment, the driving component 3 includes a driving member 32 and a connecting rod 31, and the connecting rod 31 is connected to the edge of a spare glass 2 respectively. The connecting rod 31 can rotate around the rotation axis A through the drive of the driving member 32, thereby driving the spare glass 2 to rotate around the rotation axis A, and realizing the release of the cover between the spare glasses 2 or between the spare glass 2 and the window glass 1. At the same time, the driving member 32 can be a driving rod or a driving handle. The driving method of the driving member 32 can be that the driving rod is connected to the motor and the connecting rod 31 is driven by the corresponding transmission system; or the operator can directly drive the driving handle to rotate, thereby driving the connecting rod 31 to rotate around the axis. Technical personnel in this field can reasonably configure the driving component 3 according to actual conditions, and this embodiment does not limit this.

[0039] As a preferred embodiment, there are multiple connecting rods 31, and the multiple connecting rods 31 are sequentially sleeved along the radial direction of the connecting rods 31. In this configuration, only one through hole matching the diameter of the connecting rod 31 with the largest diameter can be opened on the outer wall of the single crystal furnace, so that the connecting rod 31 can pass through, and there is no need to open multiple through holes on the outer wall of the single crystal furnace, which reduces the possibility of accidental gas leakage in the single crystal furnace, improves the airtightness of the single crystal furnace, and further improves the yield of the product.

[0040] In an alternative embodiment, the thickness of the window glass 1 in the extending direction of the rotation axis A is greater than the thickness of the spare glass 2 in the extending direction of the rotation axis A. After one or more groups of crystals have finished growing, the single crystal furnace can be stopped and opened to replace the spare glass 2 to which contaminants are attached. Considering the cost, since the spare glass 2 only blocks the attachment of oxides to the window glass 1 when oxides are accidentally generated, the spare glass 2 can be made of a very thin glass sheet, thereby reducing the cost of production and replacement.

[0041] Please refer to Figure 1 to Figure 2 , the rotation axis A is perpendicular to the plane where the spare glass 2 is located. Since the spare glass 2 and the window glass 1 are arranged parallel to each other, the rotation axis A is arranged perpendicular to the plane where the spare glass 2 is located, so that the spare glass 2 can avoid the restriction of the rotation by the window glass 1 or the outer wall of the single crystal furnace during the rotation process, thereby allowing the contaminated spare glass 2 to rotate to a position where the remaining spare glass 2 or the window glass 1 is completely exposed.

[0042] Please refer to Figure 3 In another embodiment, the utility model further provides a single crystal furnace, comprising: a furnace body 4, a furnace cover 5, and the single crystal furnace observation window as described above; the furnace body 4 is connected to the furnace cover 5 to form the outer wall of the single crystal furnace, and the single crystal furnace observation window is arranged on the furnace cover 5. It should be noted that in the present embodiment, the single crystal furnace observation window is arranged on the furnace cover 5 so that the operator can directly observe the growth process of the crystal. In other embodiments, the single crystal furnace observation window can also be arranged at other parts of the outer wall of the single crystal furnace, as long as the crystal growth can be observed in real time. With such a configuration, by using the above-mentioned single crystal furnace observation window on the single crystal furnace, the operator can continuously observe the situation in the furnace through the window glass 1 during the crystal growth process, without being affected by the oxide adhesion caused by unexpected circumstances, thereby ensuring the yield and product yield.

[0043] In summary, in the single crystal furnace observation window and the single crystal furnace provided in the embodiments of the utility model, the single crystal furnace observation window includes: window glass, spare glass and a driving assembly; the window glass is arranged on the outer wall of the single crystal furnace for observing the internal condition of the single crystal furnace; the spare glass is arranged inside the single crystal furnace and parallel to the window glass, the spare glass is in contact with the inner surface of the window glass and covers the inner surface of the window glass; the driving assembly is rotatable along the rotation axis and is connected to the edge of the spare glass, and when contaminants are attached to the inner surface of the spare glass, the driving assembly drives the spare glass to rotate along the rotation axis to release the covering of the inner surface of the window glass.

[0044] With such a configuration, by arranging spare glass on the inner side of the window glass, and the spare glass is in contact with the window glass, the spare glass covers the inner surface of the window glass. Therefore, when the crystal rod in the single crystal silicon produces oxide during the growth process, it will preferentially adhere to the inner surface of the spare glass. At this time, the spare glass is driven to rotate by the driving component, and the covering of the window glass is released, so that the operator can still observe the situation in the single crystal furnace through the window glass to ensure the smooth growth of the crystal rod, thereby improving the product yield. At the same time, considering that oxides will only appear in large quantities under unexpected circumstances, multiple spare glasses can be configured to ensure that the window glass will not be contaminated by oxides within a growth cycle, thereby reducing the frequency of shutdown maintenance and improving production efficiency.

[0045] The above description is only a description of the preferred embodiment of the utility model, and is not any limitation on the scope of the utility model. Any changes and modifications made by ordinary technicians in the field of the utility model based on the above disclosure shall fall within the scope of protection of the claims.

Claims

1. A single crystal furnace observation window, characterized in that: include: Window glass, spare glass and drive components; The window glass is arranged on the outer wall of the single crystal furnace and is used to observe the internal conditions of the single crystal furnace; The spare glass is arranged inside the single crystal furnace and parallel to the window glass. The spare glass is in contact with the inner surface of the window glass and covers the inner surface of the window glass. The driving assembly is rotatable along a rotation axis and is connected to the edge of the spare glass. When contaminants adhere to the inner surface of the spare glass, the driving assembly drives the spare glass to rotate along the rotation axis to release the covering of the inner surface of the window glass.

2. The single crystal furnace observation window according to claim 1, characterized in that: The size of the window glass matches the size of the spare glass, and the window glass and the spare glass are coaxially arranged.

3. The single crystal furnace observation window according to claim 1, characterized in that: The single crystal furnace observation window includes a plurality of spare glasses, which are arranged in sequence along the rotation axis, and two adjacent spare glasses are bonded to each other, and the spare glass far from the window glass covers the inner surface of the spare glass near the window glass.

4. The single crystal furnace observation window according to claim 3, characterized in that: When contaminants adhere to the inner surface of the spare glass that is farthest from the window glass along the rotation axis, the connected driving assembly can drive the spare glass to rotate along the rotation axis to release the covering of the inner surface of the spare glass that is in contact with it.

5. The single crystal furnace observation window according to claim 3, characterized in that: The single crystal furnace observation window includes a plurality of the driving components, and the driving components are connected to the edges of the spare glasses in a one-to-one correspondence, so that the driving components respectively drive the connected spare glasses to rotate.

6. The single crystal furnace observation window according to claim 5, characterized in that: The driving assembly includes a driving member and a connecting rod, wherein the connecting rod extends along the rotation axis and is connected to the edge of the spare glass. The driving member is arranged on a side of the connecting rod away from the spare glass and is used to drive the connecting rod to rotate along the rotation axis.

7. The single crystal furnace observation window according to claim 6, characterized in that: There are a plurality of connecting rods, and the plurality of connecting rods are sleeved in sequence along the radial direction of the connecting rods.

8. The single crystal furnace observation window according to claim 1, characterized in that: The thickness of the window glass in the extending direction of the rotation axis is greater than the thickness of the spare glass in the extending direction of the rotation axis.

9. The single crystal furnace observation window according to claim 1, characterized in that: The rotation axis is perpendicular to the plane where the spare glass is located.

10. A single crystal furnace, characterized in that: include: A furnace body, a furnace cover and a single crystal furnace observation window as claimed in any one of claims 1 to 9; The furnace body is connected to the furnace cover to form the outer wall of the single crystal furnace, and the single crystal furnace observation window is arranged on the furnace cover.

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