Airflow control device and furnace tube system for furnace tube equipment

Abstract

The present invention provides an airflow adjustment device and furnace tube apparatus for improving the uniformity of the thickness of the thin film layer on the wafer surface. [Solution] The furnace tube apparatus is equipped with a wafer boat for transporting wafers. The airflow adjustment device 100 includes a plurality of annular airflow adjustment rings 110, a plurality of airflow adjustment ring support columns 120 that extend in a first direction and are spaced apart along the outer circumference of the airflow adjustment rings and used to support the plurality of airflow adjustment rings, and a lifting mechanism connected to the airflow adjustment ring support columns, which has a lifting bracket 150, a lead screw 140 and a motor 130 for adjusting the position of the airflow adjustment rings by raising and lowering the airflow adjustment ring support columns and adjusting the airflow flowing toward the wafers on the wafer boat. The plurality of airflow adjustment rings are spaced apart along the first direction, and the central cavity of the plurality of airflow adjustment rings constitutes a housing cavity for housing the wafer boat.

Description

Technical Field

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[0001] The present invention relates to the technical field of semiconductor processes, and particularly relates to an air flow adjustment device for a furnace tube device and a furnace tube device.

Background Art

[0002] <O000009>Currently, in the semiconductor manufacturing process, it is generally necessary to deposit different types of thin films on the surface of a wafer, and a furnace tube device is widely used in the deposition process. The wafer boat of the furnace tube device accommodates the wafer and grows a thin film on the surface of the wafer by means of low-pressure chemical vapor deposition.

[0003] When depositing a thin film using a furnace tube device in the related art, the thickness of the thin film deposited in the edge region on the same wafer is thicker than that in the central region, and the uniformity of the thickness of the thin film layer on the wafer is poor. This cannot be effectively improved only by adjusting the parameters of the furnace tube device.

Summary of the Invention

[0004] In the section of the summary of the invention, a series of simplified concepts are introduced, which will be further described in detail in the section of the embodiments for implementing the invention. The section of the summary of the invention is not intended to limit the important features or essential technical features of the solution required to be protected, let alone determine the protection scope of the solution required to be protected.

Means for Solving the Problems

[0005] According to one aspect of the present invention, an airflow adjustment device for a furnace tube apparatus is provided, the furnace tube apparatus comprising a wafer boat for transporting wafers, the airflow adjustment device comprising a plurality of annular airflow adjustment rings, a plurality of airflow adjustment ring support columns extending in a first direction and spaced apart along the outer circumference of the airflow adjustment rings, wherein the distance between at least one pair of adjacent airflow adjustment ring support columns in the plurality of airflow adjustment ring support columns is greater than the radial dimension of the wafer transported on the wafer boat, the plurality of airflow adjustment ring support columns are used to support the plurality of airflow adjustment rings, the plurality of airflow adjustment rings are spaced apart along the first direction, the central cavities of the plurality of airflow adjustment rings form a housing cavity for housing the wafer boat, and a lifting mechanism connected to the airflow adjustment ring support columns for adjusting the position of the airflow adjustment rings by raising and lowering the airflow adjustment ring support columns to adjust the airflow flowing toward the wafers on the wafer boat.

[0006] Exemplary, the wafer boat comprises an upper cover plate, a lower cover plate, and a plurality of wafer support columns, the upper cover plate and the lower cover plate being connected by the plurality of wafer support columns, each of the wafer support columns having a plurality of grooves equally spaced along the first direction, the grooves being used to support and position the wafers so that the wafers are transported on the wafer boat at intervals in the first direction, and the plurality of airflow adjustment rings corresponding one-to-one with each of the grooves on the wafer support columns.

[0007] For example, when removing or placing a wafer, the lifting mechanism adjusts the position of the airflow adjustment ring support columns by raising or lowering them so that the airflow adjustment ring is in a first position, and the upper surface of each of the airflow adjustment rings is on the same plane as the lower surface of the corresponding groove in the same layer. When processing a wafer, the lifting mechanism adjusts the position of the airflow adjustment ring support columns by raising or lowering them so that the airflow adjustment ring is in a second position, and the upper surface of the airflow adjustment ring is on the same plane as the upper surface of the corresponding wafer in the same layer, or the upper surface of the airflow adjustment ring is higher than the upper surface of the corresponding wafer in the same layer.

[0008] Exemplary, the lifting mechanism comprises a lifting bracket connecting the plurality of airflow adjustment ring support columns, and a drive mechanism connected to the lifting bracket and configured to raise and lower the airflow adjustment ring support columns by driving the lifting bracket to raise and lower it.

[0009] Exemplary, the drive mechanism comprises a lead screw mounted vertically and screw-connected to the lifting bracket, and a motor connected to the lead screw and configured to rotationally drive the lead screw to move the lifting bracket up and down along the lead screw.

[0010] Exemplary, the furnace tube apparatus is provided with a support base, the drive mechanism and the airflow adjustment device are mounted on the support base, and the wafer boat has a base, the base is provided through the lifting bracket and is positioned on the support base.

[0011] Exemplary, the furnace tube apparatus is used to grow a thin film layer on a wafer held in the wafer boat, and the airflow adjustment ring is made of a material having a specific heat capacity different from that of the thin film layer.

[0012] For example, the specific heat capacity of the material of the airflow adjustment ring is smaller than the specific heat capacity of the thin film layer.

[0013] For example, the material of the airflow adjustment ring includes at least one selected from silicon, quartz, and silicon carbide.

[0014] For example, the inner diameter of the airflow adjustment ring is in the range of 304 mm to 350 mm, the outer diameter of the airflow adjustment ring is in the range of 410 mm to 550 mm, and the gap between the inner side wall of the airflow adjustment ring and the wafer boat is in the range of 2 mm to 25 mm.

[0015] According to another aspect of the present invention, a furnace tube apparatus is provided comprising the airflow adjustment device and a wafer boat for transporting wafers. [Effects of the Invention]

[0016] In the airflow adjustment device of the present invention, the central cavity of the airflow adjustment ring constitutes a accommodating cavity for accommodating a wafer, a wafer boat is used to support the wafer, and when processing a wafer, a lifting mechanism can drive the airflow adjustment ring support column within the device. Driving the airflow adjustment ring support column enables the airflow adjustment ring to be raised and lowered, and by adjusting the position of the airflow adjustment ring, the distribution of airflow passing through the wafer can be adjusted to make the airflow distribution uniform. Furthermore, the airflow adjustment ring can also help to improve the uniformity of the thickness of the thin film layer formed on the wafer by adjusting the thermal radiation field at the edge of the wafer. [Brief explanation of the drawing]

[0017] The accompanying drawings of the present invention are provided below as part of the present invention for understanding the present invention. Embodiments of the present invention and their descriptions are shown in the accompanying drawings to illustrate the principles of the present invention.

[0018] [Figure 1] Figure 1 is a diagram showing a schematic configuration of an airflow adjustment device according to an embodiment of the present invention. [Figure 2] Figure 2 is a diagram showing the schematic configuration of a wafer boat according to an embodiment of the present invention. [Figure 3]FIG. 3 is a schematic view showing a cooperative configuration of the airflow adjustment device and the wafer boat according to an embodiment of the present invention. [Figure 4] FIG. 4 is a top view showing a cooperative configuration of the airflow adjustment device and the wafer boat in an embodiment of the present invention. [Figure 5A] FIG. 5A is a schematic view showing a change in airflow in an embodiment of the present invention. [Figure 5B] FIG. 5B is a schematic view showing a change in airflow in an embodiment of the present invention. [Figure 6A] FIG. 6A is a diagram showing the relationship between the thickness and position of the thin film layer of the wafer in the related art and the present invention. [Figure 6B] FIG. 6B is a diagram showing the relationship between the thickness and position of the thin film layer of the wafer in the related art and the present invention.

Embodiments for Carrying Out the Invention

[0019] In the following description, in order to more fully understand the present invention, many specific details are shown. However, it will be apparent to those skilled in the art that the present invention can be implemented even without one or more of these details. In other embodiments, some technical features well known in the art are not described in order to avoid confusion with the present invention.

[0020] It should be understood that the present invention can be implemented in different forms and should not be construed as limited to the embodiments presented herein. Rather, by providing these embodiments, the disclosure is thorough and complete, and can fully convey the scope of the present invention to those skilled in the art. In the accompanying drawings, the dimensions of layers and zones and their relative sizes may be exaggerated for clarity. The same reference numerals throughout indicate the same elements.

[0021] When an element or layer is expressed as "··· to", "adjacent to ···", and is expressed as "connected" or "coupled" to another element or layer, it may be directly present on the other element or layer, may be adjacent, connected, or coupled to the other element or layer, and there may be intervening elements or layers. Conversely, when an element is expressed as "directly on ···", "directly adjacent to ···", or is expressed as "directly connected", "directly coupled" to another element, it should be understood to mean that there are no intervening elements or layers. Terms such as first, second, third, etc. can be used to describe various elements, components, zones, layers, and / or parts, but it should be understood that these elements, components, zones, layers, and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, zone, layer, or part from another. Therefore, without departing from the teachings of the present invention, the first element, component, zone, layer, or part described hereinafter can be represented as the second element, component, zone, layer, or part.

[0022] Spatial relationship terms such as "under ···", "lower side of ···", "lower surface of ···", "lower", "on ···", "upper side of ···", "upper surface of ···", "upper" etc. can be used in this specification for the convenience of explanation to describe the relationship between one element or feature shown in the drawings and another element or feature. It should be understood that the spatial relationship terms are intended to encompass different orientations of the device in use and operation in addition to the orientation shown in the figures. For example, if the device in the attached drawings is turned over, an element or feature described as "under the other element" or "beneath it" will be oriented "above" the other element or feature. Therefore, the exemplary terms "lower side of ···" or "under ···" may include both the "above" and "below" directions. The device may additionally be oriented (rotated 90 degrees or other orientations), and the spatial descriptions used herein will be interpreted accordingly.

[0023] The terms used herein are intended solely to describe specific embodiments and are not intended to limit the invention. Where used herein, the singular forms “one,” “one,” and “the / the” are also intended to include the plural form unless the context explicitly indicates otherwise. Furthermore, where used herein, the terms “equip” and / or “include” identify the presence of such feature, integer, step, operation, element, and / or component, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. Where used herein, the terms “and / or” include any combination of the relevant enumerated items.

[0024] To fully understand the present invention, the following description will illustrate the proposed solution by showing a detailed structure. Preferred embodiments of the present invention will be described in detail below, but in addition to these detailed descriptions, the present invention may have other embodiments.

[0025] As shown in Figures 1 and 2, one embodiment of the present invention provides an airflow adjustment device for a furnace tube apparatus. The furnace tube apparatus includes a wafer boat 200 for transporting wafers, and the airflow adjustment device 100 includes a plurality of airflow adjustment rings 110, a plurality of airflow adjustment ring support columns 120, and a lifting mechanism.

[0026] Here, the airflow adjustment ring 110 is an annular plate shape. Multiple airflow adjustment ring support columns 120 extend in a first direction and are spaced apart along the outer circumference of the airflow adjustment ring 110. The distance between at least one pair of adjacent airflow adjustment ring support columns 120 is greater than the radial dimension of the wafer on the wafer boat 200 to facilitate wafer removal and placement. Multiple airflow adjustment ring support columns 120 are used to support multiple wafers. The multiple airflow adjustment rings 110 are spaced apart along the first direction, and the central cavities of the multiple airflow adjustment rings 110 form a housing cavity for housing the wafer boat 200. Lifting mechanisms are connected to the airflow adjustment ring support columns 120 to adjust the airflow distribution over the wafers in the wafer boat 200 by raising and lowering the airflow adjustment ring support columns 120 to adjust the position of the airflow adjustment rings 110.

[0027] In the embodiment of the present invention, the airflow adjustment device can operate the airflow adjustment ring support column 120 by a lifting mechanism. Operating the airflow adjustment ring support column 120 enables the airflow adjustment ring 110 to be raised and lowered. The central cavity of the airflow adjustment ring 110 constitutes a housing cavity for accommodating a wafer boat 200 for supporting the wafer. Adjusting the position of the airflow adjustment ring 110 allows for adjustment of the distribution of airflow flowing over the wafer, thereby making the airflow distribution more uniform. The airflow adjustment ring 110 can also adjust the thermal radiation field at the edge of the wafer, thereby improving the uniformity of the thickness of the film layer formed on the wafer.

[0028] Exemplary, the first direction in the embodiment of the present invention is the vertical direction. The wafer boat 200 comprises an upper cover plate 230, a lower cover plate 240, and a plurality of wafer support columns 210. The upper cover plate 230 and the lower cover plate 240 are connected by the plurality of wafer support columns 210. Each of the wafer support columns 210 is provided with a plurality of grooves at uniform intervals along the first direction. The grooves are used to hold wafers, and wafers are supported on the wafer boat 200 at intervals in the first direction. The plurality of airflow adjustment rings 110 correspond one-to-one with the grooves provided on each of the wafer support columns 210. The structure of the upper cover plate 230 and the lower cover plate 240 forms closed sections at both ends of the wafer boat, reducing the airflow passing through the sides of the wafer boat. Alternatively, the number of grooves on each wafer support column 210 may be the same, with a one-to-one correspondence between them.

[0029] The lifting mechanism in one embodiment of the present invention will be described below with reference to Figure 3. The lifting mechanism comprises a lifting bracket 150 and a drive mechanism. Here, the lifting bracket 150 is connected to a plurality of airflow adjustment ring support columns 120, and the drive mechanism is connected to the lifting bracket 150. The drive mechanism is configured to raise and lower the airflow adjustment ring support columns 120 by driving the lifting bracket 150 to raise and lower.

[0030] For example, the lifting mechanism is configured such that when removing or placing a wafer, the position of the airflow adjustment ring support column 120 is raised or lowered to adjust the position of the airflow adjustment ring 110 to a first position where the upper surface of each airflow adjustment ring 110 is flush with the lower surface of the corresponding groove in the same layer. When processing wafers, the position to which the airflow adjustment ring support column 120 is raised or lowered is adjusted to a second position where the upper surface of each airflow adjustment ring 110 is flush with the upper surface of the corresponding wafer in the same layer, or where the upper surface of each airflow adjustment ring 110 is higher than the upper surface of the corresponding wafer in the same layer.

[0031] Specifically, when removing or placing a wafer, the airflow adjustment ring support column 120 is raised or lowered so that the airflow adjustment ring 110 is in a first position. When the airflow adjustment ring 110 is in the first position, the upper surface of the airflow adjustment ring 110 becomes flush with the lower surface of the corresponding groove, allowing wafer access to the space between the airflow adjustment rings 110. In other words, when the airflow adjustment ring 110 is controlled by the lifting mechanism to be in the first position, the airflow adjustment ring 110 and the grooves on the wafer boat 200 are offset to facilitate the loading and unloading of wafers into and out of the wafer boat 200. For example, loading and unloading wafers into and out of the wafer boat 200 is achieved by moving the wafer horizontally. When the process is executed, the airflow adjustment ring 110 is in a second position, in which case the upper surface of the airflow adjustment ring 110 may be coplanar with the upper surface of the wafer so that the airflow on the wafer is more uniform after adjustment, or it may be higher than the upper surface of the wafer to achieve the purpose of adjusting the direction of the airflow to suit different process requirements.

[0032] Exemplary, the drive mechanism comprises a lead screw 140 and a motor 130. The lead screw 140 and the lifting bracket 150 are screw-connected. The lead screw 140 is installed vertically. The motor 130 is connected to the lead screw 140. The output shaft of the motor 130 is connected to the lead screw 140, and when the motor 130 is operated, it rotates the lead screw 140. Since the lifting bracket 150 is screw-connected to the lead screw 140, when the lead screw 140 rotates, the lifting bracket 150 moves vertically along the lead screw 140, thereby driving the lifting bracket and the airflow adjustment ring support column 120. When the airflow adjustment ring support column 120 moves vertically, the airflow adjustment ring 110 moves vertically with it, thereby raising and lowering the airflow adjustment ring 110 and changing the relative position between the airflow adjustment ring 110 and the wafer boat. It should be noted that the drive mechanism in the embodiment of the present invention is merely an example, and other suitable drive mechanisms are also applicable to the present invention.

[0033] Exemplary, the wafer boat 200 is provided with a base 220 at its bottom. For example, the base 220 is connected to a lower cover plate 240 of the wafer boat 200. The base 220 is movably positioned within a lifting bracket 150. As the lead screw 140 rotates, the base 220 smoothly drives the lifting bracket 150, allowing it to be raised and lowered vertically. In one embodiment, the base 220 is positioned through the lifting bracket 150. More specifically, a housing space for the base 220 is formed in the middle of the lifting bracket 150, and the lifting bracket 150 is positioned outside the base 220, thereby enabling a movable connection between the base 220 and the lifting bracket 150, and the structure of the base 220 can be used to guide the lifting and lowering of the lifting bracket 150.

[0034] The operation process of the airflow adjustment device will be described below with reference to Figures 3-4. The housing cavity 170 of the airflow adjustment device is used to hold the wafer boat 200. Each airflow adjustment ring 110 can correspond to a wafer in the wafer boat 200. The lifting mechanism in the embodiment of the present invention is also used to adjust the position of the airflow adjustment rings 110 to facilitate the removal and placement of wafers in the wafer boat 200. For example, when removing or placing wafers, the lifting mechanism adjusts the position of the airflow adjustment ring support column 120 by raising or lowering it to position the airflow adjustment rings 110 in a first position, making the upper surface of each airflow adjustment ring 110 flush with the lower surface of the corresponding groove in the same layer. The airflow adjustment device according to the present invention is applied to a furnace tube apparatus, which includes a transport table 160, the drive mechanism and the airflow adjustment device 100 are provided on the transport table 160, and the base 220 at the bottom of the wafer boat 200 is positioned on the transport table 160. The structure of the airflow adjustment device 100 and the wafer boat 200 is supported by the transport table 160. The wafer is held in the wafer boat 200 of the furnace tube apparatus, the wafer is inserted into the groove of the wafer boat 200, and a thin film layer is grown on the wafer held in the wafer boat 200 using the furnace tube apparatus.

[0035] When processing wafers, the distribution of airflow through the wafer can be adjusted by controlling the raising and lowering of the airflow adjustment ring 110 using a lifting mechanism. For example, by raising and lowering the position of the airflow adjustment ring support column 120 using the lifting mechanism so that the airflow adjustment ring 110 is in a second position, the distribution of airflow through the wafer can be adjusted so that the upper surface of each airflow adjustment ring 110 is on the same plane as the upper surface of the corresponding wafer of the same layer, or so that the upper surface of each airflow adjustment ring 110 is higher than the upper surface of the corresponding wafer of the same layer, thereby making the airflow distribution more uniform. The airflow adjustment ring 110 can also adjust the thermal radiation field at the edge of the wafer to improve the uniformity of the thickness of the film layer formed on the wafer.

[0036] For example, the wafer boat 200 is configured to be detachably placed within the airflow adjustment device 100, and the relative position between the wafer boat 200 and the airflow adjustment device 100 can be changed by raising or lowering the airflow adjustment device 100.

[0037] The lifting mechanism drives the airflow adjustment ring 110 to shift relative to the groove in the wafer boat 200, and by supplying the wafer to be processed into the groove of the wafer boat, the wafer can be placed and removed. After the wafer is placed in the groove, the wafer boat 200 and the airflow adjustment device 100 are installed in the furnace tube apparatus to form a thin film layer on the wafer. The airflow enters the wafer boat 200 from the side of the airflow adjustment ring 110 and comes into contact with the wafer. The airflow adjustment ring 110 is adjustable by the lifting mechanism, and when its vertical position is changed, a shift occurs between the airflow adjustment ring 110 and the corresponding groove and the wafer on the groove, thereby changing the direction of the airflow. This prevents the airflow from contacting the wafer only in one direction, making the airflow distribution more uniform and improving the uniformity of the thickness of the thin film layer on the wafer.

[0038] As shown in Figures 5A and 5B, when the positions of the airflow adjustment ring 110 and the grooves correspond, for example, when the airflow adjustment ring 110 is located in a second position and each upper surface of the airflow adjustment ring 110 is coplanar with the upper surface of the corresponding wafer 300 of the same layer, the radial coverage area of ​​the airflow is lengthened, and the airflow tends to become smoother after initially entering at high speed from the edge of the airflow adjustment ring 110. As a result, the pressure difference and gas velocity difference of the gas corresponding to the entire wafer 300 are reduced, the distribution of the gas flow corresponding to each wafer is made more uniform, and the uniformity of the film thickness deposited on the wafer 300 is improved. Furthermore, if the position of the airflow adjustment rings 110 is adjusted so that the upper surface of each airflow adjustment ring 110 is higher than the upper surface of the corresponding wafer 300 of the same layer, the airflow adjustment rings 110 and the grooves will be shifted vertically, changing the position of the gas flow that directly contacts the wafer 300 as it passes through the airflow adjustment rings 110. As a result, the gas flow approaches the wafer 300 below it, allowing the gas flow distribution on the wafer 300 to be adjusted, thereby bringing the airflow distribution at the edges of the wafer 300 closer to the airflow distribution at the center of the wafer and improving the uniformity of the airflow distribution.

[0039] For example, the inner diameter of the airflow adjustment ring 110 is in the range of 304 mm to 350 mm, and the outer diameter of the airflow adjustment ring 110 is in the range of 410 mm to 550 mm. The inner diameter range of the airflow adjustment ring 110 and the outer diameter range of the wafer boat 200 are compatible with each other, and there is a certain gap between the inner circumference of the airflow adjustment ring 110 and the outer circumference of the wafer boat 200. The airflow adjustment ring 110 has a certain width in the radial direction (i.e., half the difference between the inner and outer diameters), and has an appropriate travel distance when the airflow passes through the airflow adjustment ring 110, allowing it to effectively adjust the direction of the airflow. For example, the gap between the inner sidewall of the airflow adjustment ring 110 and the outer sidewall of the wafer boat 200 is in the range of 2 mm to 25 mm. It should be noted that the above ranges are used only as examples, and other appropriate values ​​are also applicable to this invention.

[0040] To adjust the thermal radiation field at the wafer edge so that the thickness of the film deposited on the wafer becomes more uniform, the specific heat capacity of the material of the airflow adjustment ring 110 and the specific heat capacity of the film layer are, for example, different. Due to the difference in specific heat capacity, the temperature rise and fall of the airflow adjustment ring 110 and the film layer are different, and as a result, the thermal radiation field at the outer edge of the wafer can be adjusted. In a specific example, to solve the problem that the thickness of the film layer in the wafer edge region is thicker than the thickness of the film layer in the wafer central region, the specific heat capacity of the material of the airflow adjustment ring 110 is made smaller than the specific heat capacity of the film layer. This is because by making the specific heat capacity of the airflow adjustment ring 110 smaller, its own temperature can change more quickly in response to changes in ambient temperature (e.g., airflow temperature), thereby reducing thermal radiation in the wafer edge region, further reducing the film growth rate in the edge region, reducing the deposition thickness of the film layer, and improving the uniformity of the film layer. The material of the airflow adjustment ring 110 may include at least one of silicon, quartz, and silicon carbide. The material of the airflow adjustment ring 110 can be selected according to the actual conditions during manufacturing and use, and the embodiments of the present invention do not impose any limitations thereon.

[0041] Please refer to Figures 6A and 6B. Figures 6A and 6B show the correspondence between the thickness and position of the thin film layer in the related technology and in the present invention, respectively. The origin is the center of the wafer, the horizontal coordinate represents the distance from the center of the circle, and the vertical coordinate represents the thickness of the thin film layer. From this comparison, it can be seen that in the related technology, the thickness of the edge region of the thin film layer is considerably larger than the thickness of the central region, with a difference of up to 40%, but in the present invention, the difference between the thickness at the edge position and the thickness at the central position of the thin film layer is small, less than 10%. It can be seen that the present invention can effectively improve the problem of uneven thickness of the film layer.

[0042] Furthermore, embodiments of the present invention provide a furnace tube apparatus that includes an airflow adjustment device as described above and a wafer boat for transporting wafers, wherein the wafer boat 200 holds the wafer for forming a thin film layer on the wafer, and the airflow adjustment device 100 changes the direction of the airflow, thereby ensuring uniformity of the thin film layer on the wafer and providing an apparatus that can adapt to different process requirements. The furnace tube apparatus may be a low-pressure chemical vapor deposition apparatus, a high-temperature furnace tube oxidation apparatus, or another suitable thin film deposition apparatus.

[0043] In the furnace tube apparatus according to an embodiment of the present invention, the airflow adjustment ring support column 120 can be driven by a lifting mechanism, and by driving the airflow adjustment ring support column 120, the airflow adjustment ring 110 can be raised and lowered. The central cavity of the airflow adjustment ring 110 constitutes a housing cavity for housing a wafer boat 200 and is used to place wafers on the wafer boat 200. By adjusting the position of the airflow adjustment ring 110, the distribution of airflow passing through the wafer can be adjusted, thereby adjusting the thermal radiation field of the outer ring of the wafer and ensuring uniformity of the film thickness formed on the wafer.

[0044] While exemplary embodiments have been described herein with reference to the accompanying drawings, it should be understood that these exemplary embodiments are merely illustrative and are not intended to limit the scope of the invention. Those skilled in the art can make various changes and modifications without departing from the scope and spirit of the invention. All such changes and modifications are intended to fall within the scope of the invention as required by the appended claims.

[0045] Similarly, in order to streamline the invention and aid in understanding one or more of its various applications, it should be understood that in the description of exemplary embodiments of the invention, various features of the invention are sometimes grouped in individual embodiments, figures, or descriptions thereof. However, the methods of the invention should not be interpreted as reflecting an intention that the protection claimed in this application requires more features than those explicitly documented in each claim. More precisely, as reflected in the corresponding claims, the point of the invention is that the corresponding technical problem can be solved with fewer features than all the features of a given disclosed single embodiment. Thus, the claims following a particular embodiment are thereby explicitly incorporated into that particular embodiment, and each claim itself functions as a separate embodiment of the application.

[0046] Furthermore, even if some embodiments of this specification include some features included in other embodiments and do not include other features, combinations of features from different embodiments fall within the scope of the present invention and form different embodiments. For example, any one of the embodiments for which protection is claimed can be used in any combination within the claims.

[0047] The embodiments described above are illustrative of the present invention and not limiting it, and it should be noted that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. Reference numerals in parentheses within the claims should not be construed as limiting the scope of the claims. The use of terms such as "first," "second," and "third" does not indicate any order; these terms may be interpreted as names. [Explanation of symbols]

[0048] 100: Airflow adjustment device 110: Airflow adjustment ring 120: Airflow adjustment ring support column 130: Motor 140: Lead screw 150: Lifting bracket 160: Transport platform 170: Containment Cavity 200: Wafer Boat 210: Wafer support column 220: Pedestal 230: Upper cover plate 240: Lower cover plate 300: Wafer

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