Shutter assembly and chemical vapor deposition system

Abstract

The application provides a baffle assembly and a chemical vapor deposition system. The baffle assembly comprises: at least two baffle groups, which are respectively arranged in at least two temperature different filling areas of a vertical furnace; each baffle group comprises at least one baffle; the thicknesses of baffles in different baffle groups are different; the higher the temperature of the filling area where the baffle group is located, the smaller the thickness of the baffle in the baffle group. The application can make the sum of the thicknesses of the baffles and the films on the baffles in different baffle groups closer in the same reaction time, which is beneficial to reducing the thickness difference of the baffles in different baffle groups, and then the thickness monitoring step of the baffles can be synchronized, the replacement time and the cleaning time of different filling areas can be synchronized, and the efficiency of the thickness monitoring, replacement and cleaning of the baffles is improved. The edge part of the application is thinner than the middle part, the application has a convex structure, the adhesion of the baffle and the deposit can be reduced, and the baffle is convenient to take out.

Description

Technical Field

[0001] This application relates to the field of semiconductor device manufacturing technology, and more specifically, to a baffle assembly and a chemical vapor deposition system. Background Technology

[0002] In the manufacturing process of semiconductor devices, chemical vapor deposition (CVD) is often used to form thin films on the surface of wafers. Specifically, the wafer is placed in a vertical furnace of a CVD system, and a gas is introduced into the furnace to react and synthesize a thin film on the wafer surface.

[0003] Typically, multiple wafers are arranged vertically within a furnace. Due to the large space inside a vertical furnace, the temperature in some areas may not meet requirements, leading to substandard thin film synthesis rates in those areas. This results in a high defect rate of the synthesized thin films on the wafers, causing significant wafer waste. However, if the areas with substandard temperatures are left unattended, the airflow, temperature, and reactant concentration in these areas become extremely unstable and difficult to control, also significantly impacting the yield of thin films synthesized on wafers near these areas. Therefore, baffles are often installed in the areas of the vertical furnace where the temperature does not meet requirements to ensure that all wafers have the same operating conditions.

[0004] However, the prior art has at least one of the following problems:

[0005] (1) The baffles in the prior art are completely identical, and the film deposition rate in different regions is different. After the baffles are used multiple times, the film thickness on the baffles in different regions will vary more and more, which reduces the efficiency of baffle replacement, thickness monitoring or cleaning.

[0006] (2) The vertical furnace has a side groove for supporting the baffle. In the prior art, the baffle is inserted into the side groove and a film is grown. After a film of a certain thickness is grown, the baffle is easily stuck in the side groove, making it difficult to remove the baffle.

[0007] (3) In the prior art, after the baffle is inserted into the side groove, a thin film will also be deposited in the side groove and on the bottom surface of the baffle. The deposits formed are easy to fill the side groove, causing the baffle to stick to the inner wall of the side groove, making it difficult to remove the baffle. Summary of the Invention

[0008] This application provides a baffle assembly and a chemical vapor deposition system to solve the technical problems existing in related technologies, such as baffles being completely identical, the thin film thickness on different areas of the baffle becoming increasingly different after multiple uses, baffles easily getting stuck in the side groove, or deposits easily filling the side groove and causing the baffle to adhere to the inner wall of the side groove.

[0009] In a first aspect, embodiments of this application provide a baffle assembly for installation in a vertical furnace of a chemical vapor deposition system, comprising: at least two baffle groups, each correspondingly installed in at least two loading zones of different temperatures within the vertical furnace;

[0010] Each baffle group includes at least one baffle;

[0011] The thickness of the baffles in different baffle groups is different; the higher the temperature of the filling zone where the baffle group is located, the smaller the thickness of the baffles in the baffle group.

[0012] In some embodiments, the baffle includes a stacked first sacrificial layer, a first protective layer, a substrate, a second protective layer, and a second sacrificial layer; both the first and second sacrificial layers are used for removal after the thin film is grown in a vertical furnace.

[0013] In different baffle groups, at least one of the first sacrificial layer, first protective layer, substrate, second protective layer, and second sacrificial layer has a different thickness.

[0014] In some embodiments, the baffle has opposing top and bottom surfaces, with the bottom surface facing the bottom of the vertical furnace;

[0015] The baffle includes: a middle portion and an edge portion connected to the edge of the middle portion; the edge portion is used to partially insert into the side groove of the vertical furnace;

[0016] A first plane is provided parallel to the center of the bottom surface and the top surface of the middle part;

[0017] The top surface of the edge portion is closer to the first plane than the top surface of the middle portion, and the bottom surface of the edge portion is flush with the bottom surface of the middle portion; the bottom surface of the edge portion is used to partially support the side groove.

[0018] In some embodiments, the edge portion includes: a first sub-edge portion and a second sub-edge portion that are sequentially moved away from the middle portion;

[0019] The top surface of the second sub-edge is flush with the top surface of the first sub-edge, and the bottom surface of the second sub-edge is closer to the first plane than the bottom surface of the first sub-edge.

[0020] The bottom surface of the first sub-edge is used to partially support the support.

[0021] In some embodiments, the bottom surface of the second sub-edge portion has at least one protruding structure, the protruding structure does not protrude from the bottom surface of the first sub-edge portion, and the protruding structure has a distance from the first sub-edge portion;

[0022] At least one protruding structure forms a recessed area between itself and the first sub-edge portion;

[0023] The distance between the protruding structure and the support, the distance between the bottom surface of the second sub-edge and the support, and the distance between the top surface of the second sub-edge and the top of the side groove increase sequentially.

[0024] In some embodiments, the top surfaces of both the middle portion and the edge portion are formed of a second sacrificial layer;

[0025] The bottom surface of the substrate includes an initial protrusion, and a first protective layer and a first sacrificial layer conformally cover the bottom surface of the substrate in a direction away from the substrate. The initial protrusion and the portion of the first protective layer and the first sacrificial layer covering the initial protrusion form a protrusion structure.

[0026] In some embodiments, the baffle assembly includes:

[0027] The first baffle group is located in the first loading zone of the vertical furnace, closer to the air inlet;

[0028] The second baffle group is located in the second loading zone of the vertical furnace, closer to the exhaust port; the temperature of the second loading zone is higher than that of the first loading zone.

[0029] The thickness of the baffle in the first baffle group is greater than the thickness of the baffle in the second baffle group.

[0030] In some embodiments, the multiple baffles in the first baffle group have the same thickness, and the multiple baffles in the second baffle group have the same thickness.

[0031] Secondly, embodiments of this application also provide a chemical vapor deposition system, including: a vertical furnace, a wafer, and any of the baffle assemblies provided in the first aspect above;

[0032] The vertical furnace includes at least two filling zones with different temperatures, as well as a production zone;

[0033] At least two baffle groups of the baffle assembly are respectively disposed in at least two filling zones with different temperatures;

[0034] The wafers are located within the production area.

[0035] In some embodiments, the vertical furnace includes multiple side grooves; the bottom of the side grooves forms a support portion;

[0036] In the baffle assembly, the edge portion is inserted into the side groove, and along the radial direction of the baffle, the edge portion has a gap with the side wall of the side groove, and the edge of the middle portion has a gap with the top of the side groove; the bottom surface of the edge portion is placed on the support portion.

[0037] The baffle assembly and chemical vapor deposition system provided in this application have the following technical advantages:

[0038] (1) In this embodiment, by setting thinner baffles in the high-temperature loading zone and thicker baffles in the low-temperature loading zone, the sum of the thickness of the baffles and the thin film on the baffles in different baffle groups is made closer within the same reaction time, which is beneficial to reducing the thickness difference of the baffles in different baffle groups. The smaller the thickness difference, the less impact it has on the airflow, temperature or reactant concentration in the vertical furnace, which is beneficial to ensuring the consistency of wafer deposition in the vertical furnace. Moreover, since the baffles and the total thickness of the thin film on the baffles need to be replaced when they reach a critical value, and the film needs to be cleaned for recycling, the thickness of the baffles needs to be monitored. The smaller the thickness difference, the baffle thickness monitoring steps can be synchronized, as can the replacement time and cleaning time of different loading zones, thereby improving the efficiency of baffle thickness monitoring, replacement and cleaning.

[0039] (2) The baffle in this embodiment includes an edge portion and a middle portion, with the edge portion at least partially inserted into the side groove of the vertical furnace. The top surface of the edge portion is closer to the first plane than the top surface of the middle portion, and the bottom surface of the edge portion is flush with the bottom surface of the middle portion, so that a discontinuity is formed at the junction of the top surface of the edge portion and the top surface of the middle portion, thereby making the overall thickness of the edge portion less than that of the middle portion, reducing the competition for grain growth direction during the deposition process, and also making the thickness uniformity of the baffle better after the chemical vapor deposition process, which is convenient for the robot to grasp.

[0040] (3) In the embodiments of this application, the edge portion includes a first sub-edge portion and a second sub-edge portion. The bottom surface of the second sub-edge portion has a raised structure. A recessed area is formed between the raised structure and the side surface of the first sub-edge portion. The deposit is blocked outside the recessed area by the raised structure, so that a cavity is always formed between the recessed area and the support of the side groove. This helps to reduce the contact area between the edge portion and the deposit, reduce adhesion, and facilitate the removal of the baffle. Attached Figure Description

[0041] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This is one of the structural schematic diagrams of a chemical vapor deposition system provided in the embodiments of this application;

[0043] Figure 2 This is one of the structural schematic diagrams of a baffle assembly provided in an embodiment of this application;

[0044] Figure 3This is a second schematic diagram of a baffle assembly provided in an embodiment of this application;

[0045] Figure 4 This is a second schematic diagram of a chemical vapor deposition system provided in an embodiment of this application;

[0046] Figure 5 This is the third schematic diagram of a baffle assembly provided in an embodiment of this application.

[0047] Figure label:

[0048] 100-Baffle; 101-Substrate; 102-Second protective layer; 103-Second sacrificial layer; 104-Protrusion structure; 105-First protective layer; 106-First sacrificial layer; 107-Initial protrusion; 110-Edge portion; 111-First sub-edge portion; 112-Second sub-edge portion; 120-Middle portion;

[0049] 210 - First baffle group; 220 - Second baffle group;

[0050] 300 - Vertical furnace; 310 - First loading zone; 320 - Second loading zone; 330 - Side trough; 331 - Support; 332 - Side wall; 333 - Top of trough; 340 - Air inlet; 350 - Exhaust outlet; 360 - Production area;

[0051] 400 - Wafer; 500 - Deposit;

[0052] X-First plane. Detailed Implementation

[0053] The embodiments of this application are described below with reference to the accompanying drawings. It should be understood that the embodiments described below with reference to the accompanying drawings are exemplary descriptions for explaining the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions of the embodiments of this application.

[0054] Those skilled in the art will understand that, unless specifically stated otherwise, the terms "described" and "the" as used herein may also include plural forms. It should be further understood that the term "comprising" as used in this application's specification means the presence of the described features, integers, and / or components, but does not exclude implementations of other features, data, elements, components, and / or combinations thereof supported by this art. It should be understood that when we say an element is "connected to" another element, the element may be directly connected or coupled to the other element, or it may mean that the element and the other element are connected through an intermediate element. The term "and / or" as used herein refers to at least one of the items defined by the term; for example, "A and / or B" can be implemented as "A," or as "B," or as "A and B."

[0055] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0056] The baffle assembly and chemical vapor deposition system provided in this application are intended to solve the above-mentioned technical problems in related technologies.

[0057] like Figure 1 As shown, this application provides a baffle assembly for installation in a vertical furnace 300 of a chemical vapor deposition system. The baffle assembly includes at least two baffle groups.

[0058] At least two baffle groups are respectively set in at least two loading zones with different temperatures in the vertical furnace 300.

[0059] Each baffle group includes at least one baffle 100.

[0060] The thickness of the baffles 100 in different baffle groups is different; the higher the temperature of the filling zone where the baffle group is located, the smaller the thickness of the baffles 100 in the baffle group.

[0061] In this embodiment, the number of baffle groups can be n, such as the first baffle group 210, the second baffle group 220, where n is a positive integer greater than 1, for example, n=2, 3, etc. Similarly, the number of baffle groups is consistent with the number of filling zones. One baffle group is set in one filling zone. Different filling zones have different temperatures, and the thickness of the baffle groups set in different filling zones is also different. The higher the temperature of the filling zone where the baffle group is located, the smaller the thickness of all the baffles 100 in the baffle group; the lower the temperature of the filling zone where the baffle group is located, the larger the thickness of all the baffles 100 in the baffle group. Therefore, in chemical vapor deposition (CVD) processes, the deposition rate is faster in the high-temperature loading zone, so the baffles 100 in the baffle group are thinner. Conversely, the deposition rate is slower in the low-temperature loading zone, so the baffles 100 in the baffle group are thicker. This ensures that after the same deposition time, the thickness of the baffles 100 and the sum of the film thicknesses on them are closer in different baffle groups, which helps reduce the thickness difference of the baffles 100 after at least one CVD process in different baffle groups. Furthermore, since the baffles 100 and the total film thickness on them need to be replaced when they reach a critical value, and the film needs to be cleaned for recycling, the thickness of the baffles 100 needs to be monitored. A smaller thickness difference allows for simultaneous monitoring of the baffle thickness, as well as simultaneous replacement and cleaning times in different loading zones, thereby improving the efficiency of baffle thickness monitoring, replacement, and cleaning.

[0062] For example, the first baffle group is set in the first loading zone, the second baffle group is set in the second loading zone, and the third baffle group is set in the third loading zone. The temperature of the first loading zone, the second loading zone, and the third loading zone increases. The thickness of all baffles 100 in the first baffle group is greater than the thickness of all baffles 100 in the second baffle group, and the thickness of all baffles 100 in the second baffle group is greater than the thickness of all baffles 100 in the third baffle group.

[0063] Furthermore, baffles 100 of different thicknesses are set in different filling areas, and wafers 400 are set in the production area near the filling area. The thickness difference of baffles 100 in different baffle groups is within a small range. This thickness difference is not enough to affect the deposition rate of wafers near the filling area. However, the film thickness deposited in the chemical vapor deposition process is relatively thin. Therefore, after at least one chemical vapor deposition process, the thickness of baffles 100 and the total thickness of the film on baffles 100 in different baffle groups are similar.

[0064] It should be noted that when each baffle group includes multiple baffles 100, the thickness of the baffles 100 within the same baffle group may be different or the same, but they will all be thicker than the thickness of the baffles 100 in the baffle group of the filling area where the temperature is higher.

[0065] Alternatively, the filling area may be located at the top, bottom, or middle of the vertical furnace 300.

[0066] The research and development ideas of this application include: Figure 1 As shown, the vertical furnace 300 has an inlet 340 and an outlet 350. The gas volume at the inlet 340 and the outlet 350 is different. To ensure the overall uniformity of the deposited film thickness within the vertical furnace 300, the temperatures of the inlet 340 and the outlet 350 need to be fine-tuned so that the deposition rates at the inlet 340 and the outlet 350 are closer. Specifically, the temperature at the inlet 340 is reduced, and the temperature at the outlet 350 is increased. Therefore, in some embodiments, the baffle group includes: a first baffle group 210 and a second baffle group 220.

[0067] The first baffle group 210 is located in the first loading zone 310 of the vertical furnace 300, closer to the air inlet 340.

[0068] The second baffle group 220 is located in the second loading zone 320 of the vertical furnace 300, closer to the exhaust port 350; the temperature of the second loading zone 320 is higher than the temperature of the first loading zone 310.

[0069] The thickness of the baffle 100 in the first baffle group 210 is greater than the thickness of the baffle 100 in the second baffle group 220.

[0070] In this embodiment, the temperature of the first filling zone 310 is lower, and the temperature of the second filling zone 320 is higher. The thickness of the baffle 100 of the first baffle group 210 in the first filling zone 310 is greater than the thickness of the baffle 100 of the second baffle group 220 in the second filling zone 320. This makes the thickness of the baffle 100 and the film of the first baffle group 210 after the same deposition time close to or even the same as the thickness of the baffle 100 and the film of the second baffle group 220. This allows for simultaneous monitoring and replacement of the baffle 100 in the first filling zone 310 and the second filling zone 320, eliminating the need for multiple baffle 100 replacement operations in different filling zones and saving costs.

[0071] In some embodiments, the plurality of baffles 100 in the first baffle group 210 have the same thickness, and the plurality of baffles 100 in the second baffle group 220 have the same thickness.

[0072] In this embodiment, there are multiple baffles 100 in the same baffle group, all with the same thickness. After the film is grown on the baffle 100, the thickness critical value can be reached simultaneously and the baffles can be replaced at the same time. The edges are cleaned using the same cleaning process to remove the film on the baffles 100 in the same baffle group and reuse them.

[0073] Considering that thin films may be deposited on both sides of the baffle during chemical vapor deposition, in some embodiments, such as Figure 2 As shown, the baffle 100 includes a first sacrificial layer 106, a first protective layer 105, a substrate 101, a second protective layer 102, and a second sacrificial layer 103 stacked together; the second sacrificial layer 103 is used to remove the film after it has been grown in the vertical furnace 300.

[0074] The thickness of at least one of the first sacrificial layer 106, the first protective layer 105, the substrate 101, the second protective layer 102, and the second sacrificial layer 103 in different baffle groups is different.

[0075] In this embodiment, a first protective layer 105 and a second protective layer 102 cover both sides of the substrate 101. A first sacrificial layer 106 covers the bottom surface of the first protective layer 105, and a second sacrificial layer 103 covers the second protective layer 102. A thin film is deposited on the exposed surfaces of the first sacrificial layer 106 and the second sacrificial layer 103. The substrate 101 forms the basis of the baffle 100, and the integrity of the substrate 101 is related to the number of times the baffle 100 can be recycled. To control costs and protect the substrate 101, the first protective layer 105 and the second protective layer 102 are provided to protect the substrate 101. After a thin film of a certain thickness is deposited on the surfaces of the first sacrificial layer 106 and the second sacrificial layer 103, the first sacrificial layer 106 and the second sacrificial layer 103 are cleaned so that the first sacrificial layer 106 and the second sacrificial layer 103 drive the deposited thin film to be removed simultaneously. Only the substrate 101, the first protective layer 105 and the second protective layer 102 remain in the baffle 100. Then, the first sacrificial layer 106 and the second sacrificial layer 103 are grown on the surfaces of the first protective layer 105 and the second protective layer 102, respectively, to form the baffle 100, which can then be reused.

[0076] Furthermore, in this embodiment, at least one of the first sacrificial layer 106, the first protective layer 105, the substrate 101, the second protective layer 102, and the second sacrificial layer 103 in the baffle 100 of different baffle groups has a different thickness, so that the overall thickness of the baffle 100 in different baffle groups is different.

[0077] Specifically, this includes the following situations:

[0078] 1. The substrate 101 thickness of the baffles 100 in different baffle groups is different, resulting in different overall thicknesses of the baffles 100 in different baffle groups. The substrate 101 thickness of the baffles 100 in the first baffle group 210 is greater than that of the baffles 100 in the second baffle group 220, making the overall thickness of the baffles 100 in the first baffle group 210 greater than that in the second baffle group 220. The second sacrificial layer 103 and the second protective layer 102 have the same thickness, allowing the baffles 100 to use the same cleaning process, which helps control cleaning costs.

[0079] 2. The first protective layer 105 and the second protective layer 102 of the baffles 100 in different baffle groups have different thicknesses, resulting in different overall thicknesses of the baffles 100 in different baffle groups. The thickness of the protective layer 102 of the baffles 100 in the first baffle group 210 is greater than the thickness of the protective layer 102 of the baffles 100 in the second baffle group 220, making the overall thickness of the baffles 100 in the first baffle group 210 greater than the overall thickness of the baffles 100 in the second baffle group 220. Different thicknesses of the second protective layer 102 can be obtained simply by controlling the growth rate of the second protective layer 102, which is easily achieved.

[0080] 3. The first sacrificial layer 106 and the second sacrificial layer 103 of the baffles 100 in different baffle groups have different thicknesses, resulting in different overall thicknesses of the baffles 100 in different baffle groups. The thickness of the second sacrificial layer 103 of the baffles 100 in the first baffle group 210 is greater than that of the baffles 100 in the second baffle group 220, making the overall thickness of the baffles 100 in the first baffle group 210 greater than that in the second baffle group 220. Different thicknesses of the first sacrificial layer 106 and the second sacrificial layer 103 can be obtained simply by controlling their growth rates, which is easily achieved.

[0081] The research and development concept of this application also includes: the deposition rate in the middle region of the baffle 100 is slower, while the deposition rate in the edge region is faster, which leads to competition between the grain growth directions in the middle and edge regions, resulting in abnormal phenomena such as peeling and cracking. Therefore, as Figure 3 As shown, this application also provides an embodiment:

[0082] The baffle 100 has opposing top and bottom surfaces, with the bottom surface facing the bottom of the vertical furnace 300.

[0083] The baffle 100 includes a middle portion 120 and an edge portion 110 connected to the edge of the middle portion 120. The edge portion 110 is used to partially insert into the side groove 330 of the vertical furnace 300.

[0084] A first plane X is provided parallel to the center of the bottom surface and the top surface of the middle part 120.

[0085] The top surface of the edge portion 110 is closer to the first plane X than the top surface of the middle portion 120, and the bottom surface of the edge portion 110 is flush with the bottom surface of the middle portion 120; the bottom surface of the edge portion 110 is used to partially rest on the support portion 331 of the side groove 330.

[0086] In this embodiment, as Figure 3 and Figure 4 As shown, the baffle 100 is circular and has two opposing surfaces. When the baffle 100 is placed inside the vertical furnace 300, one surface of the baffle 100 faces upwards (top surface) and the other surface faces downwards (bottom surface). The top surface of the edge portion 110 is closer to the first plane X than the top surface of the middle portion 120. The bottom surface of the edge portion 110 is flush with the bottom surface of the middle portion 120, creating a discontinuity at the junction of the top surface of the edge portion 110 and the top surface of the middle portion 120. This results in the overall thickness of the edge portion 110 being less than that of the middle portion 120, reducing competition for grain growth directions during deposition and ensuring better thickness uniformity of the baffle 100 after chemical vapor deposition, making it easier for a robotic arm to grasp.

[0087] Moreover, such as Figure 4As shown, the bottom of the side groove 330 forms a support portion 331. The support portion 331, the side wall 332, and the top 333 together form the side groove 330. The edge of the support portion 331 is flush with the edge of the top 333. When the edge portion 110 is partially inserted into the side groove 330 of the vertical furnace 300, there is a gap between the edge of the middle portion 120 and the top 333 along the radial direction of the baffle 100. That is, the orthogonal projection of the edge of the top 333 at the groove opening onto the baffle 100 falls within the range of the first sub-edge portion 111 of the edge portion 110. Therefore, the discontinuity at the junction of the edge portion 110 and the middle portion 120 at the top surface can also avoid the top 333 of the side groove 330, making it easier for the baffle 100 to be removed and less likely to be blocked by the top 333 of the side groove 330.

[0088] Considering that during chemical vapor deposition, thin films may be deposited inside the side trench 330 and on the bottom surface of the baffle 100, forming deposit 500, the deposit 500 may cause the baffle to adhere to the inner wall of the side trench, making the baffle difficult to remove. Therefore, in some embodiments, such as Figure 3 and Figure 4 As shown, the edge portion 110 includes a first sub-edge portion 111 and a second sub-edge portion 112 that are sequentially located away from the middle portion 120.

[0089] The top surface of the second sub-edge portion 112 is flush with the top surface of the first sub-edge portion 111, and the bottom surface of the second sub-edge portion 112 is closer to the first plane X than the bottom surface of the first sub-edge portion 111.

[0090] The bottom surface of the first sub-edge portion 111 is used to partially support the support portion 331 of the vertical furnace 300.

[0091] In this embodiment, the edge portion 110 includes a first sub-edge portion 111 and a second sub-edge portion 112. The first sub-edge portion 111 is connected to the middle portion 120. The top surface of the first sub-edge portion 111 is closer to the first plane X than the top surface of the middle portion 120, that is, a discontinuity is formed at the junction of the top surfaces of the first sub-edge portion 111 and the middle portion 120. The bottom surface of the first sub-edge portion 111 is flush with the junction of the bottom surface of the middle portion 120. The top surface of the second sub-edge portion 112 is flush with the junction of the top surface of the first sub-edge portion 111. The bottom surface of the second sub-edge portion 112 is closer to the first plane X than the bottom surface of the first sub-edge portion 111, that is, a discontinuity is formed at the junction of the bottom surface of the second sub-edge portion 112 and the first sub-edge portion 111.

[0092] Therefore, when the edge portion 110 is partially inserted into the side groove 330 of the vertical furnace 300, the discontinuity between the top surface of the first sub-edge portion 111 and the middle portion 120 can avoid the top 333 of the side groove 330, making it easier to remove the baffle 100; the first sub-edge portion 111 is mounted on the support portion 331, and the discontinuity between the second sub-edge portion 112 and the first sub-edge portion 111 provides more buffer space for the sediment, thereby reducing the accumulation height of the sediment and reducing the possibility of adhesion between the sediment and the edge portion 110.

[0093] The research and development concept of this application also includes: when the edge portion 110 is located in the side groove 330 of the vertical furnace 300, the deposits during the deposition process may fill the space between the edge portion 110 and the side wall 332 of the side groove 330. Under high temperature conditions, the deposits may adhere to the edge portion 110, making it difficult to remove the baffle 100. Therefore, in some embodiments, the bottom surface of the second sub-edge portion 112 has at least one protruding structure 104, the protruding structure 104 does not protrude from the bottom surface of the first sub-edge portion 111, and the protruding structure 104 and the first sub-edge portion 111 are spaced apart.

[0094] At least one protruding structure 104 forms a recessed area between itself and the first sub-edge portion 111.

[0095] The distance between the protruding structure 104 and the support portion 331, the distance between the bottom surface of the second sub-edge portion 112 and the support portion 331, and the distance between the top surface of the second sub-edge portion 112 and the top 333 of the side groove 330 increase sequentially.

[0096] In this embodiment, as Figure 4 As shown, a recessed area is formed between the protruding structure 104 and the side of the first sub-edge portion 111. The deposits are blocked outside the recessed area by the protruding structure 104, so that a cavity is always formed between the recessed area and the support portion 331, which helps to reduce the contact area between the edge portion 110 and the deposits and makes it easier to remove the baffle 100. Furthermore, the distance H1 between the protruding structure 104 and the support portion 331 is smaller than the distance H2 between the bottom surface of the second sub-edge portion 112 and the support portion 331; the distance H2 between the bottom surface of the second sub-edge portion 112 and the support portion 331 is smaller than the distance H3 between the top surface of the second sub-edge portion 112 and the top 333 of the side groove 330. In this way, while ensuring that the first sub-edge portion 111 and the support portion 331 do not stick together in the cavity area between the protruding structure 104 and the first sub-edge portion 111, the top surface of the second sub-edge portion 112 and the top 333 of the side groove 330 have sufficient distance, making it easy to remove the baffle 100 and reducing the risk of the baffle 100 getting stuck in the side groove 330.

[0097] It should be noted that, Figure 4Sediment 500 is only a schematic diagram and does not represent the actual state of sediment 500. Figure 4 As shown. Understandably, the deposit 500 connects the inner walls of the baffle 100 and the side channel 330, causing adhesion between the inner walls of the baffle 100 and the side channel 330.

[0098] In some embodiments, such as Figure 5 As shown, the top surfaces of both the middle portion 120 and the edge portion 110 are formed by a second sacrificial layer 103.

[0099] In this embodiment, a second protective layer 102 can be first covered on the top surface of the substrate 101, and then a second sacrificial layer 103 can be covered on the top surface of the second protective layer 102. The edge of the second sacrificial layer 103 with a portion of its thickness is removed, that is, the top surface of the edge portion 110 is all made of the second sacrificial layer 103 material.

[0100] Optionally, the ratio of the thickness of the second sacrificial layer 103 to the thickness of the second protective layer 102 in the edge portion 110 is not less than 5:1.

[0101] Considering that the substrate 101 is generally thicker, while the first protective layer 105 and the first sacrificial layer 106 are both thinner, therefore, in some embodiments, such as Figure 5 As shown, the bottom surface of the substrate 101 includes an initial protrusion 107, a first protective layer 105 and a first sacrificial layer 106 conformally covering the bottom surface of the substrate 101 in a direction away from the substrate 101, and the initial protrusion 107 and the first protective layer 105 and the first sacrificial layer 106 covering the initial protrusion 107 partially form a protrusion structure 104.

[0102] In this embodiment, the bottom surface of the substrate 101 is etched to obtain an initial protrusion 107, and then a second protective layer 102 and a second sacrificial layer 103 are sequentially deposited on the surface of the etched substrate 101 to obtain a protrusion structure 104.

[0103] This application also provides the following embodiments:

[0104] Optionally, the substrate 101 can be a silicon substrate 101 with a thickness ranging from 400 to 1150 micrometers (inclusive), for example, 600 micrometers.

[0105] Optionally, both the first protective layer 105 and the second protective layer 102 can be films of silicon nitride material with a thickness ranging from 400 to 2000 Å (including endpoint values), for example, 600 Å.

[0106] Optionally, both the first sacrificial layer 106 and the second sacrificial layer 103 can be films of silicon dioxide material with a thickness range of 2000~8000Å (including the endpoint value), for example 4000Å.

[0107] Optionally, the first sacrificial layer 106 and the second sacrificial layer 103 serve as isolation layers, each completely covering the first protective layer 105 and the second protective layer 102. The second sacrificial layer 103 is thinnest at its edge 110, and the thickness of the second sacrificial layer 103 at the edge 110 is no less than five times the thickness of the second protective layer 102, ensuring that the second sacrificial layer 103 provides good isolation and is not easily detached from the second protective layer 102.

[0108] Optionally, the film deposited during the chemical vapor deposition process is a polycrystalline silicon film. When the polycrystalline silicon film grows to a thickness of about 10 micrometers, the baffle can be removed for replacement and cleaning.

[0109] Optionally, the baffle 100 of this application is a circular piece of at least 6 inches.

[0110] Optionally, the discontinuity height formed at the junction of the top surface of the edge portion 110 and the top surface of the middle portion 120 is in the range of 500~4000Å (including the endpoint value), for example 1000Å.

[0111] Optionally, the radial dimension of the edge portion 110 ranges from 20 to 35 mm, for example, 30 mm.

[0112] Optionally, the height of the side groove 330 is 3.5 mm, that is, the height of the side wall 332 in the groove is 3.5 mm, and the horizontal width between the side wall 332 and the opening of the side groove 330 is 5.8 mm.

[0113] Optionally, along the radial direction of the baffle 100, the distance between the edge portion 110 and the sidewall 332 of the side groove 330 is not less than 0.8 mm and not more than 1.2 mm, for example, 1 mm.

[0114] Optionally, along the radial direction of the baffle 100, the edge portion 110 inserted into the side groove 330 has a dimension of 4.6 mm to 5 mm (including the endpoint value), and the radial dimension of the second sub-edge portion 112 is less than 4.6 mm to 5 mm, so that the bottom surface of the first sub-edge portion 111 can be placed on the support portion 331, thereby forming a cavity between the protrusion structure 104 and the first sub-edge portion 111 when the deposit 500 is deposited in the side groove 330, reducing adhesion.

[0115] Based on the same inventive concept, embodiments of this application also provide a chemical vapor deposition system, including: a vertical furnace 300, a wafer 400, and any of the baffle components provided in the first aspect above.

[0116] The vertical furnace 300 includes at least two filling zones with different temperatures, and a production zone 360.

[0117] At least two baffle groups of the baffle assembly are respectively disposed in at least two filling zones with different temperatures.

[0118] Wafer 400 is located within production area 360.

[0119] In this embodiment, the baffle assembly provided in any of the above embodiments is used, and its specific structure and effect are similar, so it will not be described again here. The baffle 100 is a virtual wafer for filling, and the wafer 400 is the actual wafer for which the thin film needs to be deposited.

[0120] Optionally, the filling area includes a first filling area 310 and a second filling area 320.

[0121] In some embodiments, the vertical furnace 300 includes a plurality of side grooves 330; the bottom of the side grooves 330 forms a support portion 331.

[0122] In the baffle 100 of the baffle assembly, the edge portion 110 is inserted into the side groove 330. Along the radial direction of the baffle 100, the edge portion 110 is spaced from the side wall 332 of the side groove 330, and the edge of the middle portion 120 is spaced from the top 333 of the side groove 330. The bottom surface of the edge portion 110 rests on the support portion 331.

[0123] In this embodiment, along the radial direction of the baffle 100, the edge portion 110 is spaced from the side wall 332 of the side groove 330, and the edge of the middle portion 120 is spaced from the top 333 of the side groove 330. This can reduce the amount of gas entering the side groove 330 while ensuring that the baffle 100 can be easily removed, thereby reducing the generation of deposits and also reducing the area of ​​adhesion between the baffle 100 and the deposits.

[0124] Based on the same inventive concept, embodiments of this application also provide a management method for a baffle assembly based on any one of the above embodiments, comprising:

[0125] Different baffle groups are set up for different filling zones of the vertical furnace 300.

[0126] A database is established for the baffles 100 of the baffle group to monitor the usage parameters of each baffle 100. The usage parameters include the number of times it is used, the location of use, the initial thickness, and the thickness after use.

[0127] The baffle 100 is positioned in the same location as the previous chemical vapor deposition process, and the thickness of the baffle 100 is within a preset range.

[0128] When the thickness of the baffle 100 exceeds the preset range, the second sacrificial layer 103 of the baffle 100 is removed to confirm the effectiveness of the second protective layer 102 of the baffle 100.

[0129] This application embodiment establishes a database for each baffle 100 to facilitate monitoring of the usage of the baffle 100. When the thickness of the baffle 100 is detected to exceed the preset range, it is replaced in a timely manner, thereby improving the ease of use of the baffle 100.

[0130] By applying the embodiments of this application, at least the following beneficial effects can be achieved:

[0131] (1) In the embodiments of this application, the deposition rate is faster in the high-temperature loading zone, so the baffles 100 in the baffle group are thinner. The deposition rate is slower in the low-temperature loading zone, so the baffles 100 in the baffle group are thicker. This makes the sum of the thickness of the baffles 100 and the film on the baffles 100 more similar in different baffle groups within the same reaction time. This helps to reduce the thickness difference of the baffles 100 after at least one chemical vapor deposition process in different baffle groups. Moreover, since the baffles 100 and the total film thickness on the baffles 100 need to be replaced when they reach a critical value, and the film needs to be cleaned for recycling, the thickness of the baffles 100 needs to be monitored. The smaller the thickness difference, the more synchronous the thickness monitoring steps of the baffles 100 can be, and the synchronous replacement and cleaning times of different loading zones can also be achieved, thereby improving the efficiency of thickness monitoring, replacement and cleaning of the baffles 100.

[0132] (2) In this embodiment, the temperature of the first filling zone 310 is lower and the temperature of the second filling zone 320 is higher. The thickness of the baffle 100 of the first baffle group 210 of the first filling zone 310 is greater than the thickness of the baffle 100 of the second baffle group 220 of the second filling zone 320. This makes the thickness of the baffle 100 of the first baffle group 210 and the film after the same deposition time close to or even the same as the thickness of the baffle 100 of the second baffle group 220 and the film. This allows the baffle 100 of the first filling zone 310 and the second filling zone 320 to be monitored and replaced simultaneously. This eliminates the need to replace the baffle 100 of different filling zones multiple times, thus saving costs.

[0133] (3) In the embodiment of this application, the top surface of the edge portion 110 is closer to the first plane X than the top surface of the middle portion 120. The bottom surface of the edge portion 110 is flush with the bottom surface of the middle portion 120, so that a discontinuity is formed at the junction of the top surface of the edge portion 110 and the top surface of the middle portion 120. This makes the overall thickness of the edge portion 110 smaller than the thickness of the middle portion 120, reducing the competition for grain growth direction during the deposition process. It also makes the thickness uniformity of the baffle 100 better after the chemical vapor deposition process, which is convenient for the robot to grasp.

[0134] (4) In this embodiment of the application, when the edge portion 110 is partially inserted into the side groove 330 of the vertical furnace 300, the discontinuity between the bottom surface of the first sub-edge portion 111 and the middle portion 120 can avoid the top 333 of the side groove 330, making it easier to remove the baffle 100; the first sub-edge portion 111 is mounted on the support portion 331, and the discontinuity between the second sub-edge portion 112 and the first sub-edge portion 111 provides more buffer space for the sediment, thereby reducing the accumulation height of the sediment and reducing the possibility of adhesion between the sediment and the edge portion 110.

[0135] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A shutter assembly for use in a vertical furnace of a chemical vapor deposition system, comprising: The application relates to a shutter assembly for a vertical furnace. The shutter assembly comprises: at least two shutter groups, each of which is arranged in at least two temperature different filling areas of the vertical furnace; each of the shutter groups comprises at least one shutter; the thickness of the shutter in different shutter groups is different; the higher the temperature of the filling area where the shutter group is located, the smaller the thickness of the shutter in the shutter group; the shutter comprises a first sacrificial layer, a first protective layer, a substrate, a second protective layer and a second sacrificial layer which are stacked; the first sacrificial layer and the second sacrificial layer are used for removing after growing a thin film in the vertical furnace; the thickness of at least one of the first sacrificial layer, the first protective layer, the substrate, the second protective layer and the second sacrificial layer of the shutter in different shutter groups is different; 2. The baffle assembly of claim 1, wherein, the shutter has opposite top and bottom surfaces, and the bottom surface is used for facing the bottom of the vertical furnace; the shutter comprises a middle part and an edge part connected to the edge of the middle part; the edge part is used for being partially inserted into a side groove of the vertical furnace; a first plane is arranged in parallel with the middle of the top surface of the middle part; the top surface of the edge part is closer to the first plane than the top surface of the middle part, and the bottom surface of the edge part is flush with the bottom surface of the middle part; the bottom surface of the edge part is used for being partially arranged on a supporting part of the side groove. the edge part comprises a first sub-edge part and a second sub-edge part which are sequentially away from the middle part; the top surface of the second sub-edge part is flush with the top surface of the first sub-edge part, and the bottom surface of the second sub-edge part is closer to the first plane than the bottom surface of the first sub-edge part; 3. The baffle assembly of claim 2, wherein, the bottom surface of the first sub-edge part is used for being partially arranged on the supporting part. the bottom surface of the second sub-edge part has at least one protruding structure which is not protruded from the bottom surface of the first sub-edge part and has a spacing with the first sub-edge part; a recessed area is formed between the at least one protruding structure and the first sub-edge part; 4. The baffle assembly of claim 3, wherein, the spacing between the protruding structure and the supporting part, the spacing between the bottom surface of the second sub-edge part and the supporting part, and the spacing between the top surface of the second sub-edge part and the top of the side groove are sequentially increased. the top surfaces of the middle part and the edge part are formed by the second sacrificial layer; 5. The baffle assembly of claim 1, wherein, the bottom surface of the substrate comprises an initial protrusion, the first protective layer and the first sacrificial layer are covered on the bottom surface of the substrate in a direction away from the substrate, and the initial protrusion and the first protective layer and the first sacrificial layer covering the initial protrusion form the protruding structure. the shutter assembly comprises: a first shutter group arranged in a first filling area of the vertical furnace which is closer to an air inlet; a second shutter group arranged in a second filling area of the vertical furnace which is closer to an air outlet; the temperature of the second filling area is higher than that of the first filling area; 6. The baffle assembly of claim 5, wherein, the thickness of the shutter of the first shutter group is greater than that of the shutter of the second shutter group.

7. A chemical vapor deposition system, characterized by, the thickness of the shutters of the first shutter group is the same, and the thickness of the shutters of the second shutter group is the same. the application relates to a vertical furnace, a wafer and a shutter assembly as claimed in any one of claims 1-6. The vertical furnace comprises at least two loading zones with different temperatures and a production zone; At least two baffle assemblies are respectively arranged in the at least two loading zones with different temperatures; The wafer is arranged in the production zone.

8. The chemical vapor deposition system of claim 7, wherein, The vertical furnace comprises a plurality of side grooves, and a supporting portion is formed at the bottom of the side grooves; In the baffle assembly, the edge portion is partially inserted into the side groove, and the edge portion has a spacing from the side wall of the side groove along the radial direction of the baffle, and the edge of the middle portion has a spacing from the top of the side groove; and the bottom surface of the edge portion is partially arranged on the supporting portion.

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