Silicon carbide furnace tube and oxidizing furnace

Abstract

This invention discloses a silicon carbide furnace tube and an oxidation furnace, relating to the field of high-temperature oxidation equipment technology. The silicon carbide furnace tube includes a furnace tube support, a furnace tube assembly, a load-bearing assembly, an inlet pipe, and an outlet pipe. The furnace tube support provides structural support, and the furnace tube assembly is mounted on the furnace tube support, forming a closed internal space to provide the oxidation environment. The load-bearing assembly is located inside the furnace tube assembly and supports the material to be processed. Both the inlet and outlet pipes communicate with the area of ​​the load-bearing assembly within the furnace tube assembly for the entry and exit of process gases. At least the furnace tube assembly and the load-bearing assembly are made of silicon carbide material. Based on the technical solution disclosed in this invention, while meeting process requirements, it helps simplify the process, improves the uniformity and completeness of the reaction, and extends the service life of the furnace tube.

Description

Technical Field

[0001] This invention relates to the field of high-temperature oxidation equipment technology, specifically to a silicon carbide furnace tube and an oxidation furnace. Background Technology

[0002] As a key piece of equipment in the semiconductor manufacturing process, the oxidation furnace is mainly used to oxidize semiconductor materials in a high-temperature environment in order to grow high-quality oxide layers, such as silicon dioxide thin films.

[0003] To meet the ever-evolving production demands of semiconductor devices and integrated circuits, numerous methods for preparing silicon dioxide thin films have emerged, including high-temperature thermal oxidation, chemical vapor deposition, cathode sputtering, vacuum evaporation, epitaxial deposition, and anodic oxidation. Among these, high-temperature thermal oxidation, with its mature process and high-quality oxide layer, has become the most important method for manufacturing silicon dioxide thin films in integrated circuit manufacturing. In actual production, by introducing oxygen or water vapor into a furnace tube at a temperature of 1050°C or higher, the surface of the silicon semiconductor can be oxidized to grow a dry or wet oxide layer. This oxidation method has advantages such as relatively simple process and tight adhesion between the oxide layer and the silicon substrate, which is one of the important reasons why silicon materials have gained a dominant position in the semiconductor field.

[0004] However, with the rapid development of the semiconductor industry and the continuous improvement of chip integration, more stringent requirements have been placed on the dimensional accuracy and performance stability of semiconductor devices. Traditional oxidation furnaces mainly use silicon and quartz devices, which are prone to softening after prolonged use at temperatures above 1100℃, have a short lifespan, and involve complex processes. Today, semiconductor materials have evolved to third-generation semiconductors, represented by silicon carbide, which possess wide bandgap, high thermal conductivity, and high saturation drift velocity. Traditional oxidation furnaces can no longer meet the development needs of silicon carbide chips and urgently require improvement. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned technical deficiencies and propose a silicon carbide furnace tube and oxidation furnace to solve the technical problems of easy softening of devices, short lifespan, and complex process in the existing oxidation furnace, which makes it difficult to meet the needs of semiconductor material production.

[0006] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a silicon carbide furnace tube, comprising:

[0008] Furnace tube support, used for main body support;

[0009] A furnace tube assembly is mounted on the furnace tube support and together with the furnace tube support forms a closed tube space for providing an oxidation environment;

[0010] A support assembly, disposed inside the furnace tube assembly, is used to support the material to be processed;

[0011] Both the inlet pipe and the outlet pipe are connected to the area where the supporting component is located within the furnace tube assembly, and are used for the entry and exit of process gas;

[0012] Wherein, at least the furnace tube assembly and the support assembly are made of silicon carbide material.

[0013] In some embodiments, the furnace tube assembly includes:

[0014] An outer tube, connected to the furnace tube support, and together with the furnace tube support, encloses the internal space of the tube to provide a closed oxidation environment; and

[0015] An inner tube is disposed inside the outer tube and connected to the furnace tube support, and its interior is connected to the outer tube, for accommodating the load-bearing component.

[0016] In some embodiments, the internal space of the tube includes:

[0017] A first region, located inside the inner tube, is used to accommodate the carrier assembly; and

[0018] The second region, located between the inner tube and the outer tube, serves as a channel for process gases;

[0019] The first region and the second region are connected through an opening on the inner tube, and the first region and the second region are respectively connected to the air inlet pipe and the air outlet pipe, or the first region and the second region are respectively connected to the air outlet pipe and the air inlet pipe.

[0020] In some embodiments, a temperature measuring tube made of silicon carbide is also provided on the inner side of the inner tube. The temperature measuring tube extends along the axial direction of the inner tube and is provided with a plurality of temperature measuring probes.

[0021] In some embodiments, the carrier component includes:

[0022] A process boat, disposed inside the inner tube and equipped with a placement structure for placing the material to be processed; and

[0023] A heat-insulating base is located inside the inner tube and is disposed between the process boat and the furnace tube support for support and heat insulation.

[0024] In some embodiments, the process boat includes:

[0025] Upper baffle;

[0026] The lower baffle, spaced vertically from the upper baffle, serves as bottom support; and

[0027] Multiple boat rods are arranged between the upper baffle and the lower baffle to connect the upper baffle and the lower baffle;

[0028] Each of the multiple boat poles is provided with multiple placement slots for mutual cooperation, and the placement slots on the multiple boat poles together constitute the placement structure.

[0029] In some embodiments, the heat-insulating base includes:

[0030] The base is used for bottom support;

[0031] Multiple heat insulation panels are stacked one on top of the other on the base for heat insulation;

[0032] Multiple columns are fixedly installed on the base, and multiple heat insulation plates are sequentially and movably inserted through them to stabilize the multiple heat insulation plates;

[0033] The heat insulation board has a plurality of protrusions evenly distributed on one side. Any two adjacent heat insulation boards abut against each other through the plurality of protrusions to form a heat insulation gap between the plurality of heat insulation boards. The plurality of heat insulation boards are provided with a gap structure for preventing cracking.

[0034] Secondly, the present invention also provides an oxidation furnace, including a shell assembly, wherein the aforementioned silicon carbide furnace tube is disposed on the inner side of the shell assembly.

[0035] In some embodiments, the housing assembly is a hollow cavity with an opening on one side, comprising:

[0036] The inner furnace wall has a furnace tube space formed on its inner side to accommodate the silicon carbide furnace tube;

[0037] The outer furnace wall is fixedly installed on the outside of the inner furnace wall to separate the external space;

[0038] A heating assembly, disposed between the inner furnace wall and the outer furnace wall, is used to heat the inner furnace wall; and

[0039] A heat insulation layer is provided on the side of the outer furnace wall near the inner furnace wall to isolate heat.

[0040] In some embodiments, the outer furnace wall is further provided with a plurality of circulating water channels evenly distributed thereon, the plurality of circulating water channels being connected to water inlets and water outlets to realize the circulation of cooling water.

[0041] Compared with the prior art, the present invention provides a silicon carbide furnace tube and an oxidation furnace, wherein the furnace tube assembly is mounted on the furnace tube support, the supporting assembly is mounted inside the furnace tube assembly, the inlet pipe and the outlet pipe are both connected to the area where the supporting assembly is located inside the furnace tube assembly, and the shell assembly is mounted outside the silicon carbide furnace tube.

[0042] In this way, process gases can enter and exit the furnace tube assembly through the inlet and outlet pipes, and the shell assembly can heat the silicon carbide furnace tube. Both the furnace tube assembly and the support assembly are made of silicon carbide, which ensures that the process gases can fully contact and react with the materials to be treated, improving the uniformity and completeness of the reaction. On the other hand, the silicon carbide furnace tube assembly and support assembly can withstand higher process temperatures. While meeting the reaction temperature requirements, it can prevent the furnace tube assembly and support assembly from being corroded during subsequent cleaning, which helps to extend the service life of the furnace tube. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the overall structure of the oxidation furnace in one embodiment of the present invention;

[0044] Figure 2 This is a schematic diagram of the structure of the heat insulation layer and the water-blocking layer in one embodiment of the present invention;

[0045] Figure 3 This is a schematic diagram of the circulating water channel on the outer furnace wall in one embodiment of the present invention;

[0046] Figure 4 yes Figure 1 The enlarged view of part A in the middle is mainly used to show the connection structure between the outer tube and the furnace tube support;

[0047] Figure 5 This is a schematic diagram of the structure of the base and the column in one embodiment of the present invention;

[0048] Figure 6 This is a schematic diagram of the structure of the heat insulation plate in one embodiment of the present invention;

[0049] Figure 7 This is a schematic diagram of the structure of the process boat in one embodiment of the present invention;

[0050] Figure 8 This is a cross-sectional schematic diagram of the boat rod in one embodiment of the present invention;

[0051] Figure 9 This is a schematic diagram of the temperature measuring tube in one embodiment of the present invention.

[0052] Explanation of reference numerals in the attached figures:

[0053] 100. Shell assembly; 110. Base plate; 120. Furnace wall; 121. Inner furnace wall; 122. Outer furnace wall; 1221. Circulating water channel; 1222. Water inlet; 1223. Water outlet; 123. Heat insulation layer; 124. Water baffle layer; 130. Top cover; 140. Heating assembly; 141. Upper heating wire; 142. Side heating wire;

[0054] 200. Silicon carbide furnace tube; 210. Furnace tube support; 211. Sealing groove; 220. Furnace tube assembly; 221. Outer tube; 222. Inner tube; 230. Inlet pipe; 240. Outlet pipe; 250. Sealing ring; 260. Lock; 270. Heat insulation base; 271. Base; 2711. First positioning hole; 2712. First boss; 272. Column; 273. Heat insulation plate; 2731. Second positioning hole; 2732. Second boss; 2733. Strip seam; 280. Process boat; 281. Lower baffle; 2811. U-shaped groove; 2812. Third positioning hole; 282. Boat rod; 2821. Placement groove; 283. Upper baffle; 290. Temperature measuring tube; 291. Temperature measuring probe;

[0055] 300. Internal space; 310. First area; 320. Second area. Detailed Implementation

[0056] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0057] To address the aforementioned technical problems, this invention provides a silicon carbide furnace tube and an oxidation furnace, which, while meeting process requirements, helps simplify the process, improves the uniformity and completeness of the reaction, and extends the service life of the furnace tube.

[0058] Please see Figure 1 , Figure 1 This is a schematic diagram of the overall structure of an oxidation furnace in one embodiment of the present invention. The oxidation furnace can be used to oxidize semiconductor materials (such as wafers) to grow an oxide layer (such as a silicon dioxide oxide layer) on their surface.

[0059] The oxidation furnace includes a shell assembly 100 and a silicon carbide furnace tube 200. The shell assembly 100 can be configured as a hollow cavity structure with one open end, and the silicon carbide furnace tube 200 can enter the interior of the shell assembly 100 through the opening. In practical applications, the silicon carbide furnace tube 200 can be used to contain the material to be processed (such as semiconductor materials), and the shell assembly 100 can heat the silicon carbide furnace tube 200 to provide a high-temperature oxidation environment.

[0060] In this embodiment, the aforementioned shell assembly 100 may include a base plate 110, a furnace wall 120, and a top cover 130. The base plate 110 may have a circular opening at its center, allowing it to form an annular structure. The furnace wall 120 has a hollow cylindrical structure and can be fixedly mounted on the base plate 110. The top cover 130 can be detachably mounted above the furnace wall 120 and can close the opening at the top of the furnace wall 120.

[0061] In this way, the housing assembly 100 can form a hollow cavity structure with an open bottom and a closed top. In practical applications, the silicon carbide furnace tube 200 can enter the interior of the housing assembly 100 through the opening on the bottom plate 110.

[0062] The furnace wall 120 mentioned above includes an inner furnace wall 121 and an outer furnace wall 122. Both the inner furnace wall 121 and the outer furnace wall 122 can be configured as hollow cylindrical structures. They are set between the upper cover 130 and the bottom plate 110 and can be set coaxially.

[0063] The inner furnace wall 121 can be configured as a hollow cavity structure with an open bottom and a closed top. Its bottom can be fixedly connected to the bottom plate 110, so that a cavity for accommodating the silicon carbide furnace tube 200 can be formed on its inner side.

[0064] The outer furnace wall 122 can be configured as a hollow cylindrical structure with openings at the top and bottom. It can be coaxially fitted onto the outside of the inner furnace wall 121, and its upper and lower ends can be fixedly connected to the upper cover 130 and the bottom plate 110, respectively. In this way, the inner furnace wall 121 and the outer furnace wall 122 will form an annular cavity structure.

[0065] To meet the temperature requirements of the oxidation reaction, a heating assembly 140 can be installed between the inner furnace wall 121 and the outer furnace wall 122. The heating assembly 140 can be a heating wire, which may include an upper heating wire 141 and a side heating wire 142. The upper heating wire 141 can be fixedly installed on the side of the inner furnace wall 121 near the upper cover 130, while the side heating wire 142 can be fixedly installed on the side wall of the inner furnace wall 121 near the outer furnace wall 122.

[0066] Thus, when the upper heating wire 141 and the side heating wire 142 are energized, the upper heating wire 141 and the side heating wire 142 can directly heat the inner furnace wall 121. The heat can be further transferred to the inner side of the inner furnace wall 121 through the inner furnace wall 121, and indirectly heat the silicon carbide furnace tube 200 on the inner side.

[0067] Please see Figure 2A heat insulation layer 123 may also be provided on the side of the outer furnace wall 122 closest to the inner furnace wall 121 to isolate heat transfer to the outer furnace wall 122 and ensure that heat is transferred as much as possible to the inner side where the silicon carbide furnace tube 200 is located. This not only helps to reduce the temperature of the outer furnace wall 122 but also improves the heating effect on the silicon carbide furnace tube 200. The heat insulation layer 123 can be graphite, graphite felt, or other heat insulation materials, and there is no specific limitation on this.

[0068] like Figure 3 As shown, in order to further reduce the temperature of the outer furnace wall 122, multiple circulating water channels 1221 can be provided on the outer furnace wall 122. The multiple circulating water channels 1221 are connected to water inlets 1222 and water outlets 1223, so that cooling water can circulate on the outer furnace wall 122 to remove the heat of the outer furnace wall 122.

[0069] Based on this, the aforementioned circulating water channel 1221 can be directly formed by slotting the inner wall of the outer furnace wall 122. To prevent water from flowing out of the circulating water channel 1221, a water-blocking layer 124 can be provided between the outer furnace wall 122 and the aforementioned insulation layer 123. The water-blocking layer 124 can seal the slots on the outer furnace wall 122, thereby forming multiple circulating water channels 1221 that are closed on both sides. The material of the water-blocking layer 124 can be any material with water-blocking properties, and there are no specific limitations on this.

[0070] In one embodiment, the aforementioned circulating water channel 1221 can be configured as a spiral structure, and multiple circulating water channels 1221 can be evenly distributed along the axial direction of the outer furnace wall 122. Simultaneously, each circulating water channel 1221 can be interconnected, allowing only one inlet 1222 and one outlet 1223 to be provided on the outer furnace wall 122. In this case, the inlet 1222 and outlet 1223 can be respectively located on the upper and lower sides of the multiple circulating water channels 1221; wherein the inlet 1222 can be connected to the uppermost circulating water channel 1221, and the outlet 1223 can be connected to the lowermost circulating water channel 1221, allowing cooling water to flow through a large portion of the outer furnace wall 122 via the multiple circulating water channels 1221 to remove heat from the outer furnace wall 122, thus bringing the temperature of the outer furnace wall 122 as close to room temperature as possible.

[0071] In other embodiments, considering ease of processing, the multiple circulating water channels 1221 may not need to be interconnected. In this case, the multiple circulating water channels 1221 can be distributed vertically along the axial direction of the outer furnace wall 122, and each circulating water channel 1221 is connected to an inlet 1222 and an outlet 1223. The inlet 1222 can be connected to the upper opening of the corresponding circulating water channel 1221, and the outlet 1223 can be connected to the lower opening of the corresponding circulating water channel 1221, so that cooling water circulates in each circulating water channel 1221.

[0072] In this way, not only can the processing of the circulating water channel 1221 be improved, but the flow path of the cooling water can also be shortened, ensuring that all parts of the outer furnace wall 122 can be fully cooled, and improving the uniformity of the surface temperature distribution of the outer furnace wall 122.

[0073] Furthermore, in some embodiments, the multiple circulating water channels 1221 do not need to be connected. In this case, the upper and lower interfaces of each circulating water channel 1221 can extend to the upper and lower ends of the outer furnace wall 122 respectively; and the multiple circulating water channels 1221 can be staggered relative to each other along the axial direction of the outer furnace wall 122, so that the multiple circulating water channels 1221 form an alternating structure along the axial direction of the outer furnace wall 122. In order to improve the cooling effect, the cooling water flows in opposite directions to any two adjacent circulating water channels 1221.

[0074] Taking the setting of two circulating water channels 1221 as an example, the inlet 1222 of one circulating water channel 1221 is located at the top of the outer furnace wall 122, and the outlet 1223 is located at the bottom of the outer furnace wall 122. The inlet 1222 of the other circulating water channel 1221 is located at the bottom of the outer furnace wall 122, and the outlet 1223 is located at the top of the outer furnace wall 122.

[0075] In this way, without shortening the flow path of the cooling water, the cooling water flowing in opposite directions in multiple circulating water channels 1221 can be fully utilized to achieve mutual cooperation and complementarity, so as to ensure the uniformity of the surface temperature distribution of the outer furnace wall 122.

[0076] It should be noted that the specific number of the above-mentioned circulating water channels 1221 can be determined according to the specific cooling principle of the circulating water channels 1221 and the actual size of the shell assembly 100, and no specific limit is required.

[0077] Please see Figure 1The present invention also provides a silicon carbide furnace tube that can be used in the oxidation furnace described above. In the oxidation furnace described above, the silicon carbide furnace tube 200 can enter the housing assembly 100 through an opening at the bottom of the housing assembly 100; at this time, the silicon carbide furnace tube 200 is located inside the inner furnace wall 121, and the heating assembly 140 on the outer side of the inner furnace wall 121 can provide the silicon carbide furnace tube 200 with the high-temperature environment required for the oxidation reaction.

[0078] In this embodiment, the silicon carbide furnace tube 200 may include a furnace tube support 210, a furnace tube assembly 220, and a support component. The furnace tube assembly 220 may be integrally disposed at the bottom of the silicon carbide furnace tube 200, serving as the main support. The furnace tube assembly 220 may be disposed on the furnace tube support 210, forming a closed internal space 300 with the furnace tube support 210 to provide the reaction environment. The support component may be disposed inside the furnace tube assembly 220, and it can be used to support the material to be processed (such as semiconductor material).

[0079] Meanwhile, the furnace tube assembly 220 is also connected to an inlet pipe 230 and an outlet pipe 240, respectively. Both the inlet pipe 230 and the outlet pipe 240 are connected to the area where the inner bearing component of the furnace tube assembly 220 is located, for the entry and exit of process gas to meet the process requirements for oxide layer formation.

[0080] Specifically, the furnace tube support 210 can be configured as a disc-shaped structure, and the furnace tube assembly 220 can be vertically arranged on the side of the furnace tube support 210 near the housing assembly 100. The furnace tube assembly 220 can include an outer tube 221 and an inner tube 222. The outer tube 221 can provide a closed internal space 300, while the inner tube 222 can be used to accommodate the aforementioned load-bearing components.

[0081] Combined with appendix Figure 4 The outer tube 221 can be configured as a hollow cylindrical structure with a closed top and an open bottom. The bottom of the outer tube 221 can abut against a boss on the upper side of the furnace tube support 210. A sealing groove 211 can be provided at the abutment point of the boss, and a sealing ring 250 can be installed in the sealing groove 211. The outer tube 221 and the boss are locked together with the locking buckle 260 to ensure the stability of the outer tube 221 on the furnace tube support 210. The sealing ring 250 can be made of fluororubber or other high-temperature rubber. After the locking buckle 260 locks the outer tube 221 and the furnace tube support 210, the compression of the sealing ring 250 should be between 3% and 20% to ensure the sealing effect and service life of the sealing ring 250.

[0082] It should be noted that the outer tube 221 is closed at the top and open at the bottom; the top of the outer tube 221 can be set as an arc structure or a straight structure as needed, and there is no specific limitation on this.

[0083] Please see Figure 1The inner tube 222 can be configured as a hollow cylindrical structure with openings at the top and bottom. It is located inside the outer tube 221 and can be coaxially arranged with the outer tube 221. The lower end of the inner tube 222 can be fixedly connected to the furnace tube support 210, while its upper end can extend upward to a position close to the top of the outer tube 221. The specific distance between the two is not specifically limited.

[0084] At this point, the outer tube 221 and the furnace tube support 210 can form a closed tube space 300. This tube space 300 includes a first region 310 and a second region 320. The first region 310 is the inner side region of the inner tube 222, while the second region 320 is the region between the inner tube 222 and the outer tube 221. The first region 310 can be used to accommodate the supporting components, while the second region 320 can form a channel for process gas. Based on this, the aforementioned inlet pipe 230 and outlet pipe 240 can each connect to one of these regions.

[0085] For example, in one embodiment, both the inlet pipe 230 and the outlet pipe 240 can be mounted on the furnace tube support 210. The inlet pipe 230 can be L-shaped, with its inlet located outside the furnace tube support 210, and its outlet extending through an opening on the furnace tube support 210 to the inside of the inner tube 222, meaning the inlet pipe 230 can connect to the first region 310. The outlet pipe 240 can be a straight pipe, with its inlet connecting to the second region 320, and its outlet located outside the furnace tube support 210. Thus, the process gas can enter the first region 310 through the inlet pipe 230, then flow upwards along the wall of the inner tube 222, exiting through an opening at the top of the inner tube 222 to the second region 320, and finally, the gas (unreacted process gas or tail gas produced by the reaction) is discharged from the outlet pipe 240.

[0086] In another embodiment, the arrangement of the inlet pipe 230 and the outlet pipe 240 can be interchanged, that is, the inlet pipe 230 can be connected to the second region 320, and the outlet pipe 240 can be connected to the first region 310. In this case, the process gas first enters the second region 320 through the inlet pipe 230, and then enters the first region 310 through the opening at the top of the inner pipe 222. Finally, the gas (unreacted process gas or tail gas produced by the reaction) is discharged from the outlet pipe 240.

[0087] It is understandable that, regardless of which region (first region 310 or second region 320) the inlet pipe 230 and outlet pipe 240 are connected to, the inlet pipe 230 and outlet pipe 240 are preferably located at the bottom of the furnace tube assembly 220, so that the process gas can flow upward and fill the entire tube space 300 after entering the tube space 300, in order to ensure the uniformity and fullness of the reaction.

[0088] Meanwhile, the inlet pipe 230 and the outlet pipe 240 are preferably arranged on opposite sides of the furnace tube support 210, so that the furnace tube assembly 220 can have gas inlet on one side and gas outlet on the other side, further ensuring that the process gas can fill the entire tube space 300.

[0089] In other embodiments, the inner tube 222 can also be configured as an open-bottom, closed-top structure. In this case, to connect the first region 310 and the second region 320, an opening can be made at any position on the inner tube 222, and the first region 310 and the second region 320 can be connected through this opening. Considering the characteristics of the gas itself, this opening is preferably located near the top of the inner tube 222 to ensure a sufficiently long reaction time between the process gas and the material to be treated, thus ensuring a complete reaction.

[0090] Please see Figure 1 The aforementioned support component can be disposed inside the inner tube 222 (i.e., the first region 310), which can be used to contain the material to be treated, so that the material to be treated can fully react with the process gas in a high-temperature environment to grow a high-quality oxide layer on the surface of the material to be treated.

[0091] The support assembly includes a heat-insulating base 270, which can be positioned at the center of the furnace tube support 210. A process boat 280 is also provided on the heat-insulating base 270, which can be used to place the material to be processed (semiconductor material, such as wafer).

[0092] Combined with appendix Figure 5-6 The aforementioned heat-insulating base 270 includes a base 271, on which multiple columns 272 and multiple heat-insulating plates 273 are provided. The base 271 can be configured as a disc structure, with multiple first positioning holes 2711 extending through it. These first positioning holes 2711 can be evenly distributed circumferentially on the base 271, and the number of first positioning holes 2711 can be three, four, or more, without specific limitation.

[0093] The bottom of the base 271 has protruding bosses (which can be referred to as first bosses 2712) at the locations of each of the first positioning holes 2711. The base 271 can abut against the upper side of the furnace tube support 210 through each of the first bosses 2712. On this basis, each of the first positioning holes 2711 can be used with connecting parts to fix the base 271 and the furnace tube support 210, so that the base 271 and the furnace tube support 210 can rotate synchronously.

[0094] Multiple columns 272 can be vertically fixed on the upper side of the base 271, and the specific number of columns 272 can be set to 3, 4 or more, without specific limitation. Taking the setting of 3 columns 272 as an example, the 3 columns 272 can be evenly distributed on the base 271 in a circular manner, and each column 272 can be close to the edge of the base 271.

[0095] Multiple heat insulation panels 273 can be stacked vertically on the upper side of the base 271, and their number is not specifically limited. To accommodate each column 272, multiple second positioning holes 2731 are provided through the heat insulation panels 273. The number of second positioning holes 2731 corresponds one-to-one with the number of columns 272, so that each column 272 can be moved through the corresponding second positioning hole 2731, allowing the heat insulation panels 273 to be stably stacked on the base 271.

[0096] To ensure the heat insulation effect, a raised boss (which can be referred to as a second boss 2732) is formed on one side of each of the second positioning holes 2731. Thus, when the heat insulation plates 273 are stacked on the base 271, any two adjacent heat insulation plates 273 abut against each other through the second bosses 2732 (that is, each heat insulation plate 273 abuts against the surface of the adjacent heat insulation plate 273 that does not have a second boss 2732 through its second boss 2732), thereby forming a heat insulation gap between the heat insulation plates 273.

[0097] In addition, to prevent the insulation board 273 from cracking due to uneven heating, a gap structure for preventing cracking can also be provided on the insulation board 273.

[0098] For example, in one embodiment, a circular hole may be provided at the center of the heat insulation plate 273. In this case, the gap structure can be a strip-shaped slit 2733 that penetrates the heat insulation plate 273 vertically. One end of the strip-shaped slit 2733 can extend to the circular hole at the center of the heat insulation plate 273, forming an opening at the hole, while the other end can extend radially along the heat insulation plate 273 to the edge of the heat insulation plate 273, also forming an opening at the edge of the heat insulation plate 273. In this way, when the heat insulation plate 273 deforms due to uneven heating, the strip-shaped slit 2733 can provide the heat insulation plate 273 with the possibility of shrinkage deformation, thereby reducing the risk of cracking of the heat insulation plate 273.

[0099] It should be noted that in some embodiments, the above-mentioned gap structure can also be configured in other structural forms. For example, the strip gap 2733 is no longer a straight gap, but a curved gap extending along a specific path. This is not specifically limited as long as the purpose of preventing cracking is met. Of course, the specific dimensions of the gap structure (such as the width of the strip gap 2733 mentioned above) can also be flexibly set as needed.

[0100] Please see Figure 1 The aforementioned process boat 280 is mounted on the heat-insulating base 270. The heat-insulating base 270 not only supports the process boat 280 but also provides heat insulation.

[0101] Combined with appendix Figure 7-8 The process boat 280 includes an upper baffle 283, a lower baffle 281, and multiple boat rods 282. The upper baffle 283 and the lower baffle 281 are spaced vertically together inside the inner tube 222. The multiple boat rods 282 are arranged axially between the upper baffle 283 and the lower baffle 281 and connect the upper baffle 283 and the lower baffle 281. The multiple boat rods 282 are also equipped with a placement structure for placing the material to be processed.

[0102] For the process boat 280, the lower baffle 281 serves as a bottom support and is provided with a U-shaped slot 2811, which allows the lower baffle 281 to have a roughly U-shaped structure. Simultaneously, multiple third positioning holes 2812 are provided vertically through the lower baffle 281. These third positioning holes 2812 correspond one-to-one with the columns 272 on the aforementioned heat-insulating base 270. That is, when there are three columns 272, three corresponding third positioning holes 2812 can be provided on the lower baffle 281. The distribution of the three third positioning holes 2812 on the lower baffle 281 can be determined according to the distribution of the columns 272, ensuring that when the process boat 280 is placed on the heat-insulating base 270, each third positioning hole 2812 is aligned with its corresponding column 272.

[0103] Thus, when the entire process boat 280 is placed on the heat-insulating base 270, the process boat 280 can be inserted and engaged with the columns 272 on the heat-insulating base 270 through the third positioning holes 2812 on the lower baffle 281. The lower side of the lower baffle 281 can also abut against the heat-insulating plate 273, thereby achieving support for the process boat 280 by the heat-insulating base 270. Furthermore, multiple protrusions can also be provided on the lower side of the lower baffle 281, which can be designed with reference to the protrusions on the heat-insulating plate 273, and will not be elaborated further here.

[0104] Multiple boat rods 282 can be vertically fixed to the upper surface of the lower baffle 281, and their number can be flexibly set as needed. For example, in one embodiment, three boat rods 282 can be provided, and the three boat rods 282 can be circumferentially distributed along the outer circumference of the lower baffle 281.

[0105] To ensure the stability of the material to be processed, the three boat poles 282 are preferably distributed at equal intervals on the lower baffle 281; at the same time, the area enclosed by the three boat poles 282 is preferably provided with a sufficiently large opening area to facilitate the placement of the material to be processed between the three boat poles 282.

[0106] For example, in one embodiment, the three boat rods 282 can be distributed on the same circumference on the lower baffle 281, and the lines connecting the three boat rods 282 along the corresponding circumferential directions can form only half a circumference, so that the area corresponding to the other half of the circumference can form a 180° entrance on the process boat 280. At this time, the angle between the line connecting any two adjacent boat rods 282 and the center of the circle can be 90°, and the entrance they form is preferably consistent with the opening direction of the U-shaped slot 2811 mentioned above.

[0107] Based on this, the aforementioned placement structure is set on three boat poles 282 and can be used to place the material to be processed. However, it is understood that the specific structural form of this placement structure can be set according to the actual structural form of the material to be processed.

[0108] For example, in one embodiment, the placement structure is mainly used for placing wafers. In this case, each of the three boat rods 282 is provided with multiple placement slots 2821, and the placement slots 2821 on each boat rod 282 can cooperate with each other to place wafers.

[0109] Specifically, taking any one of the boat rods 282 as an example, multiple placement slots 2821 can be spaced apart along the axial direction of the boat rod 282, preferably in an equally spaced manner. Meanwhile, the orientation of the multiple placement slots 2821 can be consistent. For example, the multiple placement slots 2821 can be located on the side of the corresponding boat rod 282 near the center of the lower baffle 281, and the opening direction of the multiple placement slots 2821 can simultaneously face the center of the circumference of each boat rod 282.

[0110] Taking any one of the placement slots 2821 as an example, under the premise of ensuring the stability of wafer placement, the specific shape and size of the placement slot 2821 can be determined according to the shape and size of the wafer. For example, the placement slot 2821 can be set as a flat slot or as a wedge-shaped slot (such as a trapezoidal slot) with an opening angle. However, in order to improve the convenience of wafer placement, the placement slot 2821 is preferably set as a wedge-shaped slot structure, so that the opening angle of the placement slot 2821 on the side near the center of the lower baffle 281 is greater than the opening angle at its bottom position, making it convenient to put the wafer into the placement slot 2821.

[0111] In other embodiments, to further improve the convenience of wafer placement, the arrangement of the placement slots 2821 on the three boat rods 282 can be differentiated. For example, the openings of the placement slots 2821 on the two boat rods 282 closest to the entrance direction can be appropriately tilted towards the entrance direction (e.g., tilted 3-15°).

[0112] Based on this, the aforementioned upper baffle 283 is disposed at the upper end of the multiple boat rods 282, and can connect each boat rod 282 simultaneously to improve the stability of the structure. At this time, the upper baffle 283 can be configured as a semi-circular structure according to the distribution of the multiple boat rods 282, that is, the upper baffle 283 can extend along the circumference of the multiple boat rods 282 and be fixedly connected to the upper end of each boat rod 282 in sequence.

[0113] Understandably, through the above method, the wafer can enter between the three boat rods 282 from the entrance direction of the circle formed by the three boat rods 282. The placement slots 2821 on the three boat rods 282 at the same height can cooperate with each other and be used to place the same wafer. The cooperation method is as follows: when the wafer is placed between the three boat rods 282, the edge of the wafer sequentially enters the three placement slots 2821 at the same height and forms an embedded fit with the three placement slots 2821. In this way, the three placement slots 2821 respectively contact three points on the outer circumference of the wafer, thereby providing support and limiting the wafer to ensure the stability of the wafer placement.

[0114] Based on this, the placement slots 2821 on each boat rod 282 cooperate with each other to form the aforementioned placement structure.

[0115] It should be noted that, through the above arrangement, the outer tube 221 can form a closed tube space 300 with the furnace tube, and the inner tube 222 can divide the tube space 300 into a first region 310 and a second region 320. The process boat 280 can be set in the first region 310 and can be supported by the heat insulation base 270 on the furnace tube support 210. The heat insulation base 270 can rotate synchronously with the furnace tube.

[0116] Specifically, with the aid of heating component 140, shell assembly 100 can provide the necessary temperature for the reaction of the materials to be processed on process boat 280. Based on this, such as... Figure 9As shown, to ensure the ambient temperature meets the reaction requirements, the silicon carbide furnace tube 200 may also include a temperature measuring tube 290. The temperature measuring tube 290 can be disposed within the first region 310 (i.e., inside the inner tube 222) and can be located between the process boat 280 and the inner wall of the inner tube 222. Specifically, the bottom of the temperature measuring tube 290 can be fixed to the furnace tube support 210 by a bracket, and the temperature measuring tube 290 can extend upward along the axial direction of the inner tube 222. Multiple evenly distributed temperature measuring probes 291 can be disposed on the temperature measuring tube 290, and each temperature measuring probe 291 can cooperate with the industrial control system to monitor the temperature of the first region 310 in real time.

[0117] It should be noted that, in order to further meet the high-temperature environment required for the oxidation treatment of semiconductor materials and to ensure the service life of the furnace tube, the outer tube 221, inner tube 222, process boat 280, heat insulation plate 273, heat insulation plate 273 base 271, and temperature measuring tube 290 can all be made of sintered silicon carbide ceramic material, and preferably, the purity of the material should be greater than or equal to 99.995%. Based on this, the silicon carbide furnace tube 200 can withstand a high-temperature environment of 1600℃ and has the advantage of resistance to strong acids and alkalis, which can prevent it from being corroded during subsequent cleaning.

[0118] Of course, silicon carbide material can be selected for any part of the silicon carbide furnace tube 200 that requires high temperature resistance, and there is no specific limitation on this.

[0119] To better understand this invention, the following is combined with... Figure 1 The technical solutions of the embodiments of the present invention will be described in detail below:

[0120] In practical applications, the housing assembly 100 can be hoisted entirely above the silicon carbide furnace tube 200, and the entire silicon carbide furnace tube 200 can be accessed through the opening at the bottom of the housing assembly 100. The housing assembly 100, through its heating element 140, can provide the required high-temperature environment for the silicon carbide furnace tube 200.

[0121] Based on this, the process gas can enter the inner side of the inner tube 222 from the inlet pipe 230 and flow to the second region 320 from the top opening of the inner tube 222. Finally, the unreacted process gas and the tail gas produced by the reaction can be discharged from the outlet pipe 240.

[0122] In this process, the material to be processed (such as a wafer) is placed in various placement slots 2821 on the process boat 280, which can react with the process gas in a high-temperature environment and grow the required high-quality oxide layer.

[0123] In this way, both the furnace tube assembly 220 and the support assembly are made of silicon carbide, and the flow path of the process gas is reasonably set. On the one hand, this ensures that the process gas can fully contact and react with the material to be treated, improving the uniformity and completeness of the reaction. On the other hand, the core components of the silicon carbide furnace tube 200 can withstand higher process temperatures to meet the reaction temperature requirements, and can prevent the furnace tube assembly 220 and the support assembly from being corroded during subsequent cleaning, which helps to extend the service life of the furnace tube.

[0124] In the description of this application, it should be noted that the terms "upper" and "lower," etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0125] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, 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 said element.

[0126] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A silicon carbide furnace tube, characterized in that, include: Furnace tube support, used for main body support; A furnace tube assembly is mounted on the furnace tube support and together with the furnace tube support forms a closed tube space for providing an oxidation environment; A support assembly is disposed inside the furnace tube assembly, comprising a process boat and a heat insulation base. The process boat is provided with a placement structure for placing the material to be processed, and the heat insulation base is disposed between the process boat and the furnace tube support for support and heat insulation. Both the inlet pipe and the outlet pipe are connected to the area where the supporting component is located within the furnace tube assembly, and are used for the entry and exit of process gas; Wherein, at least the furnace tube assembly and the supporting assembly are made of silicon carbide material; the heat insulation base includes a base, multiple heat insulation plates and multiple columns; the base is used for bottom support; the multiple heat insulation plates are stacked on the base for heat insulation; the multiple columns are fixedly installed on the base and sequentially movably pass through the multiple heat insulation plates for stabilizing the multiple heat insulation plates; one side of each heat insulation plate is provided with multiple protrusions evenly distributed, and any two adjacent heat insulation plates abut against each other through the multiple protrusions to form a heat insulation gap between the multiple heat insulation plates, and each of the multiple heat insulation plates is provided with a slit structure for preventing cracking.

2. The silicon carbide furnace tube according to claim 1, characterized in that, The furnace tube assembly includes: An outer tube, connected to the furnace tube support, and together with the furnace tube support, encloses the internal space of the tube to provide a closed oxidation environment; and An inner tube is disposed inside the outer tube and connected to the furnace tube support, and its interior is connected to the outer tube, for accommodating the load-bearing component.

3. The silicon carbide furnace tube according to claim 2, characterized in that, The space inside the tube includes: A first region, located inside the inner tube, is used to accommodate the carrier assembly; and The second region, located between the inner tube and the outer tube, serves as a channel for process gases; The first region and the second region are connected through an opening on the inner tube, and the first region and the second region are respectively connected to the air inlet pipe and the air outlet pipe, or the first region and the second region are respectively connected to the air outlet pipe and the air inlet pipe.

4. The silicon carbide furnace tube according to claim 2, characterized in that, The inner tube is also provided with a temperature measuring tube made of silicon carbide. The temperature measuring tube extends along the axial direction of the inner tube and is provided with multiple temperature measuring probes.

5. The silicon carbide furnace tube according to claim 1, characterized in that, The process boat includes: Upper baffle; The lower baffle, spaced vertically from the upper baffle, serves as bottom support; and Multiple boat rods are arranged between the upper baffle and the lower baffle to connect the upper baffle and the lower baffle; Each of the multiple boat poles is provided with multiple placement slots for mutual cooperation, and the placement slots on the multiple boat poles together constitute the placement structure.

6. An oxidation furnace, characterized in that, It includes a housing assembly, the inner side of which is provided with a silicon carbide furnace tube as described in any one of claims 1-5.

7. The oxidation furnace according to claim 6, characterized in that, The housing assembly is a hollow cavity with an opening on one side, comprising: The inner furnace wall has a furnace tube space formed on its inner side to accommodate the silicon carbide furnace tube; The outer furnace wall is fixedly installed on the outside of the inner furnace wall to separate the external space; A heating assembly, disposed between the inner furnace wall and the outer furnace wall, is used to heat the inner furnace wall; and A heat insulation layer is provided on the side of the outer furnace wall near the inner furnace wall to isolate heat.

8. The oxidation furnace according to claim 7, characterized in that, The outer furnace wall is also provided with multiple circulating water channels that are evenly distributed. These circulating water channels are connected to water inlets and outlets to realize the circulation of cooling water.

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