Graphite boat for coating silicon-based wafer

Abstract

The invention relates to a graphite boat for coating a silicon-based wafer, and the graphite boat comprises a plurality of graphite boat sheets which are arranged in an array; the ceramic sleeves are arranged between the adjacent graphite boat sheets and are used for separating the adjacent graphite boat sheets; and the ceramic rod penetrates through the ceramic sleeve and is used for connecting the graphite boat sheets into a whole. Wherein the graphite boat piece comprises a boat piece body, an electrode connecting part and an inserting piece which is detachably connected with the boat piece body, and the electrode connecting part is respectively connected with a positive electrode and a negative electrode of an external power supply; the boat piece body is provided with a plurality of bearing parts used for loading silicon-based wafers, and the insertion pieces are detachably connected corresponding to the bearing parts. According to the invention, the problem of wafer back surface winding plating can be effectively solved, the stability and efficiency of the coating process are improved, and the requirements of the modern microelectronic industry on high-quality film preparation are met.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor preparation, and in particular to a graphite boat used for coating silicon-based wafers. Background Art

[0002] Silicon wafer coating is a key process in semiconductor manufacturing and is widely used in integrated circuits, microelectromechanical systems (MEMS), optoelectronic devices, and other fields. The coating process typically uses physical vapor deposition (PVD) or chemical vapor deposition (CVD) technology to form high-quality thin films on the wafer surface to achieve functions such as conductivity, insulation, protection, or optical properties. The graphite boat is an important component for supporting the wafer, and its structure directly affects the coating quality. However, although existing silicon wafer coating technology is quite mature, existing coating equipment and graphite boats have the following problems in practical applications: The electric field distribution in traditional graphite boats can be uneven, leading to uneven material deposition during the coating process, affecting the performance and reliability of the film. During the coating process, slight movement of the wafer can affect the uniformity of the film layer and even cause defects. Existing fixing methods make it difficult to balance precise positioning with ease of operation. Graphite boats are prone to local overheating or uneven heat conduction in high-temperature environments, affecting film quality and potentially shortening the life of the equipment. Traditional graphite boats are complex in structure and difficult to clean, which can easily lead to the accumulation of coating residues, affecting the quality of the next round of coating. Gaps between the wafer and the boat allow plasma or gas to bypass the back of the deposition layer, causing bypass plating.

[0003] Therefore, the existing technology needs to be improved. Summary of the Invention

[0004] In the prior art, existing coating equipment and graphite boats have problems such as wafer fixing stability and winding plating in practical applications. Therefore, the present invention provides a graphite boat for silicon-based wafer coating to solve the above problems.

[0005] To achieve the above object, the present invention provides a graphite boat for silicon-based wafer coating, comprising: Graphite boats, a plurality of graphite boats are arranged in an array; A ceramic sleeve is provided between adjacent graphite boats to separate the adjacent graphite boats; A ceramic rod is provided through the ceramic sleeve and is used to connect the graphite boat sheets into a whole; Among them, the graphite boat includes a boat body, an electrode connecting part and an insert that is detachably connected to the boat body, and the electrode connecting part is respectively connected to the positive and negative poles of the external power supply; a plurality of supporting parts are provided on the boat body for loading silicon-based wafers, and the insert is detachably connected to the corresponding supporting parts.

[0006] In one implementation, the insert is arranged at the top of the boat body, and the insert includes an insert body portion and an insert bearing portion of an integrated structure. The thickness of the insert body portion is the same as the thickness of the boat body, the thickness of the insert bearing portion is the same as the thickness of the bearing portion, and the insert bearing portion and the bearing portion are jointly used for loading silicon-based wafers.

[0007] In one implementation, the insert further includes engaging portions provided on both sides of the insert body, the boat body includes a slot corresponding to the engaging portions, and the thickness of the engaging portions is smaller than the thickness of the insert body.

[0008] In one implementation, the bearing portion is disposed in the middle of the boat body, and a plurality of the bearing positions are evenly arranged along the length direction of the boat body.

[0009] In one implementation, the bearing portion is a circular groove structure with the same or different diameters.

[0010] In one implementation, the graphite boat further includes process points for accurately positioning and fixing the silicon-based wafer, and the boat body is provided with positioning holes corresponding to the process points.

[0011] In one implementation, each of the bearing portions includes three positioning holes, including a support positioning hole provided below the bearing portion and side positioning holes provided on both sides of the bearing portion.

[0012] In one implementation, graphite nuts are provided at both ends of the ceramic rod, and the graphite nuts are used to lock and fix the plurality of graphite boats.

[0013] In one implementation, the graphite boat includes a positive graphite boat for connecting to a positive electrode and a negative graphite boat for connecting to a negative electrode; in the positive graphite boat, the electrode connection block is a positive electrode connection plate, and two of the positive electrode connection plates are respectively arranged on both sides of the boat body and located at the upper part of the boat body; in the negative graphite boat, the electrode connection plate is a negative electrode connection plate, and two of the negative electrode connection plates are arranged on both sides of the boat body and located at the lower part of the boat body.

[0014] In one implementation, the graphite boat further includes spacers, which are used to assist in connecting graphite boat sheets with the same electrode. The spacers are connected and fixed to each other via the ceramic rod and the graphite nut.

[0015] Beneficial Effects: The graphite boat for silicon-based wafer coating provided by the present invention utilizes a detachable structure between the insert and the boat body, allowing the insert to lift the wafer from the back and seal the edge of the graphite boat, forming a sealed chamber, effectively solving the problem of backside coating. Furthermore, the use of ceramic sleeves and ceramic rods to insulate the graphite boat ensures electric field control and equipment safety during the coating process. The modular and easy-to-assemble graphite boat for silicon-based wafer coating provided by the present invention is suitable for large-scale parallel wafer coating processes, and offers excellent process compatibility and easy maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the overall structure of a graphite boat for silicon-based wafer coating provided by the present invention; Figure 2 yes Figure 1 A partial enlarged view of a graphite boat used for coating silicon-based wafers is shown; Figure 3 yes Figure 1 A front view of a graphite boat for coating silicon-based wafers is shown; Figure 4 yes Figure 4 Schematic diagram of the exploded structure of a graphite boat for coating silicon-based wafers; Figure 5 yes Figure 4 A partial enlarged view of the coating process for silicon-based wafers is shown; Figure 6 yes Figure 4 The overall structural diagram of the insert shown; Among them, the schematic diagram of each number in the figure is: 10. Graphite boat; 101. Positive graphite boat; 102. Negative graphite boat; 11. Boat body; 111. Carrying part; 112. Slot; 113. Positioning hole; 12. Electrode connecting part; 121. Positive electrode connecting plate; 121. Negative electrode connecting plate; 13. Insert; 131. Insert body; 132. Insert carrying part; 133. Engaging part; 20. Ceramic sleeve; 30. Ceramic rod; 40. Process point; 50. Graphite nut; 60. Spacer.

[0017] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the descriptions of the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" described below mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the technical features involved in the various embodiments of the present invention can be combined with each other as long as they do not conflict with each other.

[0019] See also Figure 1-Figure 5 , Figure 1 This is a schematic diagram of the overall structure of the graphite boat for silicon-based wafer coating provided by the present invention. Figure 2 yes Figure 1 The enlarged view of the graphite boat used for coating silicon wafers is shown. Figure 3 yes Figure 1 The front view of the graphite boat used for coating silicon wafers is shown. Figure 4 yes Figure 1 The exploded structure diagram of the graphite boat used for silicon-based wafer coating is shown in FIG. Figure 5 yes Figure 4 A partial enlarged view of the coating process for silicon-based wafers is shown.

[0020] The present invention provides a graphite boat for coating silicon-based wafers, comprising: Graphite boats 10, wherein a plurality of graphite boats 10 are arranged in an array; A ceramic sleeve 20 is provided between adjacent graphite boats 10 to separate adjacent graphite boats 10; A ceramic rod 30 is provided through the ceramic sleeve 20 and is used to connect the graphite boat 10 into a whole; Among them, the graphite boat 10 includes a boat body 11, an electrode connecting part 12 and an insert 13 detachably connected to the boat body 11, and the electrode connecting part 12 is respectively connected to the positive and negative poles of the external power supply; a plurality of supporting parts 111 are provided on the boat body 11 for loading silicon-based wafers, and the insert 13 is detachably connected to the corresponding supporting parts 111.

[0021] For details, see Figure 6 , Figure 6 yes Figure 4The schematic diagram of the overall structure of the insert is shown. The insert 13 is arranged at the top of the boat body 11. The insert 13 includes an insert body portion 131 and an insert bearing portion 132 of an integrated structure. The thickness of the insert body portion 131 is the same as that of the boat body 11, and the thickness of the insert bearing portion 132 is the same as that of the bearing portion 111. The insert bearing portion 132 and the bearing portion 111 are used together to load silicon-based wafers.

[0022] By aligning the thickness of the insert body 131 with that of the boat body 11, a smooth surface can be ensured. By providing the insert bearing portion 132, the insert 13 is precisely docked with the bearing portion 111, achieving seamless edge interlocking when loading silicon-based wafers, further improving the positioning stability of the silicon-based wafers and preventing vibration and displacement. The insert 13 can absorb the silicon-based wafer from the back of the boat body 11 and seal the boat after the silicon-based wafer is placed, thereby preventing plating around the contact surface between the wafer and the boat.

[0023] Furthermore, the insert 13 also includes a snap-fit portion 133 disposed on both sides of the insert body 131. The boat body 11 includes a slot 112 corresponding to the snap-fit portion 133. The thickness of the snap-fit portion 133 is less than the thickness of the insert body 131, enabling the provision of the slot 112. More specifically, the length of the snap-fit portion 133 does not exceed the length of the insert body 131. The width of the snap-fit portion 133 at one end 133b of the snap-fit portion 133 near the insert bearing portion 132 is less than the width of the snap-fit portion 133 at one end 133a near the insert body 131, facilitating the insertion of the snap-fit portion 133. The provision of the snap-fit portion 133 ensures the insert 13 is stably fixed, preventing loosening during the coating process and ensuring a tight connection between the insert 13 and the boat body 11, further sealing the gap and improving the anti-winding coating effect. In addition, the insert 13 can be quickly assembled and disassembled and reused, thereby improving maintenance efficiency.

[0024] Specifically, the bearing portion 111 is arranged in the middle position of the boat body 11, and the multiple bearing positions 111 are evenly arranged along the length direction of the boat body 11. Each of the bearing portions 111 can carry a silicon-based wafer, and multiple silicon-based wafers can be carried in the length direction of a graphite boat 10, that is, multiple silicon-based wafers can be deposited and coated at one time, thereby improving the efficiency of silicon-based wafer deposition and coating. At the same time, the uniform arrangement in the length direction ensures the uniformity of the thermal field and electric field when coating multiple wafers, and improves the consistency and yield of simultaneous processing of multiple wafers. Furthermore, the bearing portion 111 is a circular groove structure of the same or different diameters, so that it can adapt to wafers of different sizes. At the same time, the circular groove can provide multi-point support to ensure that the wafer is stable and does not slip. In this embodiment, four bearing positions 111a of the first diameter and three bearing positions 111b of the second diameter are provided on the boat body 11, wherein the first diameter is smaller than the second diameter.

[0025] Furthermore, the graphite boat 10 also includes a process point 40 for accurately positioning and fixing the silicon-based wafer, and a positioning hole 113 corresponding to the process point 40 is provided on the boat body 11. Accurate placement and alignment are achieved through the process point 40, ensuring the accuracy of the coating pattern and reducing defects caused by wafer offset. Combined with the setting of the process point 40 and the insert 13, it is possible to ensure that the wafer is accurately positioned and fixed, prevent the wafer from moving or offsetting during the coating process, and improve the consistency of the coating. In this embodiment, each of the bearing parts 111 includes three positioning holes 113, including a support positioning hole 113 provided below the bearing part 111 and side positioning holes 113 provided on both sides of the bearing part 111. Three process points 40 are correspondingly provided through the three positioning holes 113 to form a stable structure for three-point positioning, which can prevent the wafer from rotating or tilting, and ensure that the wafer fits the insert 13 to close the edge gap.

[0026] Furthermore, the ceramic sleeve 20 is made of a high-temperature resistant ceramic material and is used to isolate adjacent boat sheets, ensure electrical insulation between the boat sheets, and prevent short circuits or current leakage. Graphite nuts 50 are provided at both ends of the ceramic rod 30, and the graphite nuts 50 are used to lock and fix the multiple graphite boat sheets 10. The ceramic rod 30 and the graphite nut 50 are connected by threads to ensure that the graphite boat structure is tight and stable, and is easy to disassemble and maintain. In addition, the ceramic rod 30 is insulated and can avoid electrode short circuits; the graphite nut 50 is resistant to high temperatures and corrosion, and improves the life of the device; the ceramic sleeve 20 has good insulation performance, good hardness and good wear resistance, which can increase the service life of the ceramic sleeve 20 as an insulating sleeve; through the ceramic rod 30, the ceramic sleeve 20 and the graphite nut 50, all the boat sheets are fixed into a whole, ensuring that the overall structure of the graphite boat is stable, improving durability, and preventing mechanical deformation in high temperature environments.

[0027] Specifically, the graphite boat 10 includes a positive graphite boat 101 for connecting to the positive electrode and a negative graphite boat 102 for connecting to the negative electrode. In the positive graphite boat 101, the electrode connection block 12 is a positive electrode connection plate 121, two of which are disposed on either side of the boat body 11 and located above the boat body 11. In the negative graphite boat 102, the electrode connection plates are negative electrode connection plates 122, two of which are disposed on either side of the boat body 11 and located below the boat body 11. It should be noted that during installation, the positive graphite boat 101 and the negative graphite boat 102 are spaced apart, i.e., the positive graphite boat 101 and the negative graphite boat 102 are installed in alternating order.

[0028] The graphite boat also includes spacers 60, which are used to assist in connecting graphite boat segments 10 with the same electrode. The spacers 60 are connected and fixed to each other via the ceramic rods 30 and the graphite nuts 50. The multi-point fixation of the spacers 60 improves the rigidity of the entire boat, ensures the same potential of the same electrode segments, reduces voltage differences, and improves electric field stability.

[0029] The assembly process of the graphite boat is as follows: a plurality of graphite boat sheets 10 are arranged in an array order, ensuring that the positive and negative poles thereof are facing in the same direction and the electrode connection parts are on the same side or on the upper and lower sides; a ceramic sleeve 20 is inserted between every two adjacent graphite boat sheets to achieve electrical insulation and spacing control; the ceramic rod 30 passes through the through holes on the ceramic sleeve 20 and the graphite boat sheet 10 in turn to connect the boat sheets in series. The graphite nuts 50 are tightened at both ends of the ceramic rod 30 to achieve overall fixation. The insert 13 is inserted into the slot 112 at the top of the boat sheet body 11 so that the snap-fitting part 133 matches and snaps into the slot 112 to ensure that the insert 13 is stably fixed. The process point 40 is embedded in the three preset snap-fitting holes 113 around each bearing part 111 to achieve three-point positioning. The positive electrode connecting plate 121 of the positive graphite boat 101 is connected to the positive pole of the power supply; the negative electrode connecting plate 122 of the negative graphite boat 102 is connected to the negative pole of the power supply; a spacer 60 is used to assist in the connection between the graphite boats of the same pole and fixed by a ceramic rod 30 to improve the electrical consistency and structural stability of the entire boat.

[0030] The working process of the graphite boat is as follows: the silicon-based wafers are placed in sequence in the multiple supporting parts 111 on the boat body 11 with the assistance of the insert 13; the positive electrode sheet and the negative electrode sheet of the graphite boat are connected to the positive and negative poles of the power supply respectively, and when powered on, current is generated and passes through the boat body 11; vapor deposition is carried out in a vacuum chamber, and the material is deposited on the surface of the wafer in the form of gas; after the coating is completed, the power is turned off and the graphite boat is allowed to cool; the wafers are taken out in sequence and the coating quality is checked.

[0031] Among them, the insert bearing portion 132 and the bearing portion 111 of the insert 13 jointly provide stable support for the wafer; the process point 40 and the edge of the wafer achieve three-point precise positioning to prevent slippage and rotation; the insert 13 absorbs the wafer from the back of the boat and seals the edge, effectively reducing the phenomenon of wafer edge plating during coating. The closed structure between the insert 13 and the boat body 11 can prevent excess material from entering under the edge of the wafer; the process point 40 ensures that the wafer will not move during the deposition process, ensuring uniform coating thickness and morphology; multiple bearing positions 111 are evenly arranged along the length direction, so that multiple wafers are heated and the electric field is evenly distributed, improving the overall yield and consistency. The insert 13 can be quickly disassembled, cleaned and reused, improving system maintenance efficiency; if the boat needs to be replaced or cleaned, the graphite nut 50 can be removed and the ceramic rod 30 can be taken out to complete the disassembly and assembly.

[0032] In general, the graphite boat for silicon-based wafer coating provided by the present invention has a detachable structure of the insert 13 and the boat body 11, so that the insert 13 supports the wafer from the back and seals the edge of the graphite boat 10, forming a sealed cavity, accurately fixing the wafer, avoiding winding and displacement, and effectively solving the problem of winding on the back of the wafer; at the same time, the ceramic sleeve 20 and the ceramic rod 30 are used to insulate the graphite boat 10, ensuring the electric field control and equipment safety of the coating process. The overall structure of the graphite boat for silicon-based wafer coating provided by the present invention is modular and easy to assemble. The overall structure is a stable mechanical structure, which enhances the life and reliability of the equipment; the detachable insert 13 can be easily maintained and cleaned, reduces coating residue, and improves production efficiency. It is suitable for high-precision semiconductor manufacturing, can effectively improve the stability and efficiency of the coating process, and meet the needs of the modern microelectronics industry for high-quality thin film preparation.

[0033] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A graphite boat for coating silicon-based wafers, characterized in that: It includes: Graphite boats, a plurality of graphite boats are arranged in an array; A ceramic sleeve is provided between adjacent graphite boats to separate the adjacent graphite boats; A ceramic rod is provided through the ceramic sleeve and is used to connect the graphite boat sheets into a whole; Among them, the graphite boat includes a boat body, an electrode connecting part and an insert that is detachably connected to the boat body, and the electrode connecting part is respectively connected to the positive and negative poles of the external power supply; a plurality of supporting parts are provided on the boat body for loading silicon-based wafers, and the insert is detachably connected to the corresponding supporting parts.

2. The graphite boat for silicon-based wafer coating according to claim 1, characterized in that: The insert is arranged at the top of the boat body, and the insert includes an insert body part and an insert bearing part of an integrated structure. The thickness of the insert body part is the same as the thickness of the boat body, the thickness of the insert bearing part is the same as the thickness of the bearing part, and the insert bearing part and the bearing part are jointly used for loading silicon-based wafers.

3. The graphite boat for coating silicon-based wafers according to claim 1, characterized in that: The insert also includes engaging parts arranged on both sides of the insert body, the boat body includes engaging grooves corresponding to the engaging parts, and the thickness of the engaging parts is smaller than the thickness of the insert body.

4. The graphite boat for silicon-based wafer coating according to claim 1, characterized in that: The bearing portion is arranged at the middle position of the boat body, and a plurality of the bearing positions are evenly arranged along the length direction of the boat body.

5. The graphite boat for silicon-based wafer coating according to claim 1, characterized in that: The bearing parts are circular groove structures with the same or different diameters.

6. The graphite boat for silicon-based wafer coating according to claim 1, characterized in that: The graphite boat also includes process points for accurately positioning and fixing the silicon-based wafer, and the boat body is provided with positioning holes corresponding to the process points.

7. The graphite boat for coating silicon-based wafers according to claim 6, characterized in that: Each of the carrying parts includes three positioning holes, including a support positioning hole arranged below the carrying part and side positioning holes arranged on both sides of the carrying part.

8. The graphite boat for coating silicon-based wafers according to claim 1, characterized in that: Graphite nuts are provided at both ends of the ceramic rod, and the graphite nuts are used to lock and fix the multiple graphite boats.

9. The graphite boat for silicon-based wafer coating according to claim 1, characterized in that: The graphite boat includes a positive graphite boat for connecting to a positive electrode and a negative graphite boat for connecting to a negative electrode; in the positive graphite boat, the electrode connection block is a positive electrode connection plate, and two of the positive electrode connection plates are respectively arranged on both sides of the boat body and located at the upper part of the boat body; in the negative graphite boat, the electrode connection plate is a negative electrode connection plate, and two of the negative electrode connection plates are arranged on both sides of the boat body and located at the lower part of the boat body.

10. The graphite boat for coating silicon-based wafers according to claims 8 and 9, characterized in that: The graphite boat further includes spacers, which are used to assist in connecting graphite boat sheets with the same electrode. The spacers are connected and fixed to each other via the ceramic rods and the graphite nuts.

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