Boat structure

Abstract

The utility model discloses a boat structure, which comprises a supporting frame body and a plurality of supporting pieces fixedly arranged on the supporting frame body and arranged in a linear array, a bearing gap for accommodating a wafer is arranged between two adjacent supporting pieces, and the bearing gap comprises a mounting gap and a flow expanding gap. According to the boat structure, the flow expansion gaps are further arranged in the bearing gaps on the supporting frame body, and the center distance between adjacent wafers is increased, so that the circulation path of process gas is prolonged, the contact time of the process gas and the wafers is prolonged, the local gas concentration difference is reduced, the diffusion of the process gas is more uniform, and the yield of the wafer is improved. And the oxidation uniformity can be effectively improved by further reacting with the wafer, and the surface processing quality of the wafer is improved.

Description

Technical Field

[0001] This application relates to the field of wafer fabrication technology, and more particularly to a boat structure. Background Technology

[0002] In the manufacturing process of SiC (silicon carbide) devices, the uniformity of the gate oxide layer is extremely important, and the design of the boat, as a key tool for supporting the wafer, directly affects the process environment (such as temperature and airflow).

[0003] Most existing boats adopt silicon carbide boat structures. By using SiC materials, the overall temperature uniformity of the boat can be improved. However, there are problems such as insufficient thermal conductivity stability and single gas flow path, which leads to local gas concentration differences and large temperature gradients on the wafer surface, affecting the consistency of oxidation reaction and gate oxide uniformity (spatial consistency of gate oxide layer thickness). Utility Model Content

[0004] This application provides a boat structure that is simple in structure and can improve the uniformity of the gate oxide layer.

[0005] To achieve the above objectives, this application provides the following technical solution.

[0006] This application provides a boat structure, including:

[0007] Support frame;

[0008] Multiple support members are provided on the support frame body;

[0009] The plurality of the support members are arranged in a linear array along the length of the support frame;

[0010] Along the length of the support frame, a bearing gap for accommodating the wafer is provided between two adjacent support members. The bearing gap includes an installation gap and a current-expanding gap arranged in layers along the length of the support frame.

[0011] In some embodiments, the height of the bearing gap is set to 7.8~13mm along the length of the support frame.

[0012] In some embodiments, the support frame includes a mounting frame and positioning support rods and limiting support rods disposed on the mounting frame;

[0013] The positioning support rod and the limiting support rod are arranged in parallel, and multiple support members are linearly arrayed and fixedly arranged on the positioning support rod and the limiting support rod along their own axial direction, respectively.

[0014] The support member on the positioning support rod and the support member on the limiting support rod are aligned radially on the positioning support rod and the limiting support rod.

[0015] In some embodiments, two limiting support rods are provided on the mounting frame, and the two limiting support rods are arranged symmetrically about the reference plane;

[0016] The reference surface passes through the central axis of the positioning support rod.

[0017] In some embodiments, the positioning support rod is fixedly connected to the mounting frame, and the mounting frame is also fixedly provided with an adjustment component, and the limiting support rod is installed on the adjustment component;

[0018] The adjustment component can adjust the relative distance between the limiting support rod and the positioning support rod.

[0019] In some embodiments, the adjustment assembly includes a slide rail fixedly mounted on the mounting frame and a slider fixedly mounted on the limiting support rod and slidably connected to the slide rail.

[0020] In some embodiments, the angle between the extension direction of the slide rail and the reference surface is less than 90°;

[0021] The distance between the end of the slide rail closest to the positioning support rod and the reference surface is less than the distance between the end of the slide rail furthest from the positioning support rod and the reference surface.

[0022] In some embodiments, the adjustment assembly further includes a limit seat fixedly mounted on the mounting frame and used to limit the sliding travel of the slider on the slide rail.

[0023] In some embodiments, the limiting support rod is rotatably connected to the slider;

[0024] And / or, it also includes a positioning lock for limiting the relative rotation of the limit support rod and the slider.

[0025] In some embodiments, the support member is provided with a through groove along the length direction of the support frame.

[0026] This application has at least the following beneficial effects:

[0027] 1. A flow-expanding gap is further set in the bearing gap on the support frame, which increases the center distance between adjacent wafers, thereby extending the flow path of the process gas and increasing the contact time between the process gas and the wafer, reducing the local gas concentration difference, making the diffusion of the process gas more uniform, and further reacting with the wafer can effectively improve the oxidation uniformity and improve the surface processing quality of the wafer.

[0028] 2. Setting the bearing gap to 7.8~13mm increases the process gas flow space between adjacent wafers, thereby extending the flow path of CO (carbon monoxide) and making its diffusion more uniform. CO (carbon monoxide) can further react with the semiconductor wafer to improve oxidation uniformity, thereby ensuring the spatial consistency of the gate oxide layer thickness.

[0029] 3. For wafers of different specifications, by adjusting the relative distance between the limiting support rod and the positioning support rod, the diameter of the inscribed circle formed by the central axis of the positioning support rod and the central axis of the limiting support rod can be adjusted, thereby achieving support matching for wafers of different diameters;

[0030] 4. Since the limiting support rod is rotatably connected to the slider and the support component is fixedly mounted on the limiting support rod, the orientation of the support component on the limiting support rod can be adjusted when the limiting support rod is rotated, thereby adjusting the support position of the support component on the limiting support rod and further improving the adaptability to wafers of different specifications.

[0031] 5. By setting through slots on the support, the contact area between the support and the wafer can be reduced, thereby increasing the contact area between the process gas and the wafer, and further improving the reaction uniformity of the wafer. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the boat structure according to an embodiment of this application;

[0033] Figure 2 This is a schematic diagram of the boat structure according to an embodiment of this application;

[0034] Figure 3 This is an enlarged structural diagram of the "bearing gap" portion in the boat structure of an embodiment of this application;

[0035] Figure 4 This is a schematic diagram of the "adjustment component" part in the boat structure of an embodiment of this application;

[0036] Figure 5 This is an enlarged structural diagram of the "adjustment component" part in the boat structure of an embodiment of this application;

[0037] Figure 6 This is a structural schematic diagram of the "supporting component" in the boat structure of an embodiment of this application.

[0038] Figure Labels

[0039] Base plate-110, top cover-120, adjustment assembly-200, limit seat-210, transition groove-220, slide rail-230, accommodating cavity-240, slider-250, positioning support rod-310, limit support rod-320, support member-330, connecting part-331, connecting arc part-332, support part-333, through groove-334, bearing gap-400, installation gap-410, current expansion gap-420, wafer-500, positioning lock-600. Detailed Implementation

[0040] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0041] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0042] The boat structure provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0043] Example 1

[0044] like Figures 1 to 6 As shown, this application provides a boat structure, including a support frame and a plurality of support members 330 linearly arrayed in the vertical direction and fixedly disposed on the support frame. A load-bearing gap 400 for accommodating a wafer 500 is provided between two adjacent support members 330.

[0045] The wafer 500 can contact the outer surface of the support 330 away from the ground, and the bearing gap 400 includes the mounting gap 410 and the amplification gap 420 located on the side of the mounting gap 410 away from the ground.

[0046] It is understandable that when the wafer 500 is installed, it is placed in the mounting gap 410 between two adjacent support members 330, and the bottom is in contact with the outer surface of the support member 330 away from the ground. At this time, the wafer 500 is located at the corresponding position of the mounting gap 410, and the flow space of the process gas can be increased through the flow expansion gap 420.

[0047] In this embodiment, the above-mentioned boat structure is adopted, and a flow-expanding gap 420 is further provided in the bearing gap 400 on the support frame, which increases the center distance between adjacent wafers 500, thereby extending the flow path of the process gas and increasing the contact time between the process gas and the wafer 500, reducing the local gas concentration difference, making the diffusion of the process gas more uniform, and further reacting with the wafer 500 can effectively improve the oxidation uniformity and improve the surface processing quality of the wafer 500.

[0048] In one embodiment, the height of the bearing gap 400 is specifically set to 7.8~13mm.

[0049] It should be noted that traditional boats mostly use silicon carbide boats with a center-to-center spacing of 5.2mm between adjacent wafer carrier slots. Because the gap between two adjacent wafers is small, the space for process gas flow is small.

[0050] Specifically, the working principle in the oxidation reaction of SiC (silicon carbide) wafers is as follows:

[0051] SiC + 3 / 2O2 = SiO2 + CO;

[0052] In an ideal SiC oxidation reaction, the products are SiO2 and CO (carbon monoxide). CO (carbon monoxide) gas itself still has oxidizing properties. However, the traditional boat uses a 5.2mm pitch, which means that CO (carbon monoxide) gas is pumped away as soon as it is released from the semiconductor wafer and has not yet diffused evenly. This results in insufficient contact between CO (carbon monoxide) gas and the semiconductor wafer, and the reaction uniformity can only be achieved at about 2.5%.

[0053] In this embodiment, the above-mentioned boat structure is used, and the bearing gap 400 is set to 7.8~13mm, which increases the process gas flow space between adjacent wafers 500, thereby extending the flow path of CO (carbon monoxide) and making its diffusion more uniform. CO (carbon monoxide) can further react with the semiconductor wafer to improve oxidation uniformity, thereby ensuring the spatial consistency of the gate oxide layer thickness.

[0054] Verification has shown that using the above-mentioned parameters for the bearing gap 400 can reduce the flow rate of the process gas by 10% to 20% and improve the uniformity of the oxidation reaction by 30% to 50%.

[0055] Understandably, for traditional wafer carriers with a 5.2mm pitch, it is possible to increase the gap between two adjacent wafers by using a slotted wafer placement method (equivalent pitch of 7.8~13mm), thereby increasing the process gas flow space between two adjacent wafers. However, since the wafer carrier slots between adjacent wafers include space for accommodating the thickness of the wafer itself, the use of slotted placement will result in wasted longitudinal space in the wafer carrier. Under the same longitudinal space, the wafer carrying capacity will be reduced, affecting production capacity.

[0056] In this embodiment, the spacing between two adjacent support members 330 is directly increased without considering the thickness of the wafer itself. Compared with the method of placing wafers in slots, more wafers can be supported in the same vertical space, thereby increasing production capacity.

[0057] It is understandable that the reaction effect can be improved by increasing the reaction temperature or reducing the process gas flow rate. Increasing the reaction temperature can increase the positive reaction and reduce the side reaction, while reducing the reaction gas flow rate can reduce the reaction rate and make the reaction more uniform.

[0058] However, the above method may cause changes in the gate oxide quality, with the electrical parameter Rdson (on-resistance) changing by 20% or more.

[0059] Example 2

[0060] like Figures 1 to 6 As shown, this application provides a boat structure, including a support frame and a support member 330 disposed on the support frame.

[0061] The support frame includes a mounting frame and positioning support rods 310 and limiting support rods 320 mounted on the mounting frame. The positioning support rods 310 and limiting support rods 320 are arranged in parallel. Multiple support members 330 are linearly arrayed and fixedly mounted on the positioning support rods 310 and limiting support rods 320 along the longitudinal direction. The support members 330 on the positioning support rods 310 and limiting support rods 320 are aligned radially with the positioning support rods 310 and limiting support rods 320. A bearing gap 400 for placing the wafer 500 is provided between two adjacent support members 330 in the longitudinal direction.

[0062] The load-bearing gap 400 can adopt any of the structural forms in Embodiment 1 above.

[0063] The positioning support rod 310 is fixedly connected to the mounting frame, and the mounting frame is also fixedly provided with an adjustment component 200. The limiting support rod 320 is installed on the adjustment component 200. The adjustment component 200 can adjust the relative distance between the limiting support rod 320 and the positioning support rod 310 to match the diameter of the wafer 500.

[0064] In this embodiment, the above-described boat structure is used. For wafers 500 of different specifications, the diameter of the inscribed circle formed by the central axis of the positioning support rod 310 and the central axis of the limiting support rod 320 can be adjusted by adjusting the relative distance between the limiting support rod 320 and the positioning support rod 310, thereby achieving support matching for wafers 500 of different diameters.

[0065] In one implementation, such as Figure 1 , Figure 2 , Figure 4 As shown, two limit support rods 320 are provided on the mounting frame, and the two limit support rods 320 are symmetrically arranged about the reference plane.

[0066] Among them, the reference surface passes through the central axis of the positioning support rod 310, and the projections of the two limiting support rods 320 and the positioning support rod 310 in the longitudinal direction form a triangular structure.

[0067] It is understood that the number of limiting support rods 320 on the mounting frame and their projected shape relative to the positioning support rods 310 are not limited to the one mentioned above. An inscribed circle can be determined by the central axis of the positioning support rods 310 and the limiting support rods 320. This inscribed circle needs to match the diameter of the wafer 500 to ensure that the support members 330 on the positioning support rods 310 and the limiting support rods 320 can effectively support the wafer 500.

[0068] It should also be noted that the support of the support member 330 on the wafer 500 should ensure that the center of gravity of the wafer 500 does not shift. Therefore, the contact point between the support member 330 and the wafer 500 should ensure that the center of gravity of the wafer 500 falls within the triangular support area formed by the three support members 330 at the corresponding positions.

[0069] In one implementation, such as Figure 1 , Figure 2 , Figure 4 , Figure 5 As shown, the adjustment assembly 200 includes a slide rail 230 and a slider 250. The slide rail 230 is fixedly mounted on the mounting frame, and the slider 250 is fixedly mounted on the limit support rod 320 and slidably connected to the slide rail 230.

[0070] In one implementation, such as Figure 1 , Figure 2 , Figure 4 , Figure 5 As shown, the angle between the extension direction of slide rail 230 and the reference plane is less than 90°.

[0071] The distance between the end of the slide rail 230 closest to the positioning support rod 310 and the reference surface is less than the distance between the end of the slide rail 230 furthest from the positioning support rod 310 and the reference surface.

[0072] Understandably, since there is an angle between the extension direction of the slide rail 230 and the reference surface, when the slider 250 slides on the slide rail 230, it can adjust the distance between the limiting support rod 320 and the reference surface and the positioning support rod 310, thereby adjusting the side length of the triangle structure formed by the longitudinal projection of the two limiting support rods 320 and the positioning support rod 310, and further adjusting the diameter of the inscribed circle formed by the central axis of the positioning support rod 310 and the central axis of the limiting support rod 320, so as to achieve support matching for wafers 500 of different specifications.

[0073] In one implementation, such as Figure 1 , Figure 2 , Figure 4 , Figure 5 As shown, the adjustment assembly 200 also includes a limit seat 210 fixedly mounted on the mounting frame and used to limit the sliding stroke of the slider 250 on the slide rail 230.

[0074] In one implementation, such as Figure 1 , Figure 2 , Figure 4 , Figure 5 As shown, the limiting seat 210 is provided with a receiving cavity 240, and the slide rail 230 is fixedly installed in the receiving cavity 240.

[0075] The limiting seat 210 is also provided with a transition groove 220 that communicates with the accommodating cavity 240. The slider 250 is disposed in the accommodating cavity 240 and is slidably connected to the slide rail 230. The limiting support rod 320 passes through the transition groove 220 and is connected to the slider 250.

[0076] When the slider 250 slides on the slide rail 230 until it contacts the inner wall of the accommodating cavity 240, the position of the limiting support rod 320 relative to the positioning support rod 310 is restricted, and at this time the limiting support rod 320 reaches the end of the adjustment stroke.

[0077] It is understood that the limiting form of the limiting support rod 320 is not limited to the one mentioned above. For example, the stroke end point of the limiting support rod 320 can also be set to contact the inner wall of the transition groove 220. As long as the stroke of the limiting support rod 320 can be limited, it will not be elaborated here.

[0078] In one embodiment, the limiting support rod 320 is rotatably connected to the slider 250.

[0079] In this embodiment, the above-described boat structure is adopted. Since the limiting support rod 320 is rotatably connected to the slider 250, and the support member 330 is fixedly installed on the limiting support rod 320, when the limiting support rod 320 is rotated, the orientation of the support member 330 on the limiting support rod 320 can be adjusted, thereby adjusting the support position of the support member 330 on the limiting support rod 320, further improving the adaptability to wafers 500 of different specifications.

[0080] In one embodiment, a positioning lock 600 is also included to limit the relative rotation of the limiting support rod 320 and the slider 250.

[0081] In one implementation, such as Figures 1 to 6 As shown, Figure 1 , Figure 2 , Figure 4 , Figure 5 As shown, the positioning lock 600 is threadedly connected to the limiting support rod 320, and the end near the limiting seat 210 can contact the limiting seat 210.

[0082] When the positioning lock 600 is rotated, its position on the limiting support rod 320 can be adjusted. After the angle of the limiting support rod 320 relative to the slider 250 is adjusted, the positioning lock 600 is rotated to contact the limiting seat 210. Under the action of the friction between the positioning lock 600 and the limiting seat 210, the rotation of the limiting support rod 320 relative to the slider 250 is restricted, thereby realizing the positioning of the support member 330 on the limiting support rod 320.

[0083] It is understood that the rotation limiting structure of the limiting support rod 320 is not limited to the one mentioned above. For example, an electromagnetic brake can also be set between the limiting support rod 320 and the slider 250, as long as the positioning of the support member 330 on the limiting support rod 320 can be achieved. This will not be elaborated here.

[0084] In one implementation, such as Figure 1 , Figure 2 As shown, the mounting frame includes a base plate 110 and a top cover 120 arranged parallel to the base plate 110. A positioning support rod 310 and a limiting support rod 320 are disposed between the base plate 110 and the top cover 120.

[0085] The positioning support rod 310 is fixedly connected to the base plate 110 and the top cover 120 at both ends. The base plate 110 and the top cover 120 are respectively provided with two adjustment components 200 at the corresponding positions of the limiting support rod 320. The two ends of the limiting support rod 320 are respectively connected to the adjustment components 200 at the corresponding positions of the base plate 110 and the top cover 120.

[0086] Example 3

[0087] like Figures 1 to 6 As shown, this application provides a boat structure, including a support frame and a plurality of support members 330 linearly arrayed in the vertical direction and fixedly mounted on the support frame.

[0088] Among them, a bearing gap 400 for accommodating the wafer 500 is provided between two adjacent support members 330, and the wafer 500 can contact the outer surface of the support member 330 away from the ground. A through groove 334 is provided on the support member 330 along the longitudinal direction.

[0089] The structure of the support frame and the arrangement of the support members 330 can adopt any of the structural forms disclosed in Embodiments 1 and 2 above.

[0090] In this embodiment of the application, the above-mentioned boat structure is adopted. By providing a through groove 334 on the support member 330, the contact area between the support member 330 and the wafer 500 can be reduced, thereby increasing the contact area between the process gas and the wafer 500 and further improving the reaction uniformity of the wafer 500.

[0091] In one implementation, such as Figures 1 to 6 As shown, the support member 330 includes a connecting part 331, a connecting arc part 332 and a support part 333. The through groove 334 is located on the side of the connecting part 331 away from the ground and is arranged at a distance from the connecting part 331. The connecting arc part 332 is fixedly disposed between the connecting part 331 and the support part 333.

[0092] The connecting part 331 is fixedly connected to the support frame, the support part 333 is used to support the wafer 500, and the through slot 334 is disposed through the support part 333.

[0093] Understandably, the spacing between the connection part 331 and the through groove 334 further increases the flow space of the process gas, thereby improving the uniformity of the reaction between the process gas and the wafer 500.

[0094] In one implementation, such as Figures 1 to 6 As shown, the outer surface of the support part 333 away from the ground is set as a horizontal plane, and the connecting arc part 332 is specifically set as an inclined member with its two ends fixedly connected to the connecting part 331 and the support part 333 respectively.

[0095] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0096] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A boat structure, characterized by, include: Support frame; Multiple support members are provided on the support frame body; The plurality of the support members are arranged in a linear array along the length of the support frame; Along the length of the support frame, a bearing gap for accommodating the wafer is provided between two adjacent support members. The bearing gap includes an installation gap and a current-expanding gap arranged in layers along the length of the support frame.

2. A boat structure according to claim 1, wherein Along the length of the support frame, the height of the bearing gap is set to 7.8~13mm.

3. A boat structure according to claim 1, wherein The support frame includes an installation frame and positioning support rods and limiting support rods disposed on the installation frame; The positioning support rod and the limiting support rod are arranged in parallel, and multiple support members are linearly arrayed and fixedly arranged on the positioning support rod and the limiting support rod along their own axial direction, respectively. The support member on the positioning support rod and the support member on the limiting support rod are aligned radially on the positioning support rod and the limiting support rod.

4. A boat structure according to claim 3, wherein Two limiting support rods are provided on the mounting frame, and the two limiting support rods are arranged symmetrically about the reference plane; The reference surface passes through the central axis of the positioning support rod.

5. A boat structure according to claim 4, characterized in that, The positioning support rod is fixedly connected to the mounting frame, and an adjustment component is also fixedly provided on the mounting frame. The limiting support rod is installed on the adjustment component. The adjustment component can adjust the relative distance between the limiting support rod and the positioning support rod.

6. A boat structure according to claim 5, characterized in that, The adjustment assembly includes a slide rail fixedly mounted on the mounting frame and a slider fixedly mounted on the limiting support rod and slidably connected to the slide rail.

7. A boat structure according to claim 6, wherein The angle between the extension direction of the slide rail and the reference surface is less than 90°; The distance between the end of the slide rail closest to the positioning support rod and the reference surface is less than the distance between the end of the slide rail furthest from the positioning support rod and the reference surface.

8. A boat structure according to claim 6, wherein The adjustment assembly also includes a limiting seat that is fixedly mounted on the mounting frame and used to limit the sliding travel of the slider on the slide rail.

9. A boat structure according to claim 6, wherein The limiting support rod is rotatably connected to the slider. And / or, it also includes a positioning lock for limiting the relative rotation of the limit support rod and the slider.

10. A boat structure according to claim 1, wherein The support member has a through groove extending along the length of the support frame.

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