Chemical vapor deposition furnace for inner and outer two-component cylindrical workpieces

Abstract

The present invention discloses a chemical vapor deposition furnace for an inner and outer dual-component cylindrical workpiece, comprising a furnace body, a heat preservation device, a heater arranged in the heat preservation device, a process gas charging system, an exhaust system, and an upper barrier ring. A deposition chamber is arranged in the heat preservation device; the upper barrier ring and the cylindrical workpiece separate the deposition chamber into an outer chamber area and an inner chamber area; the process gas charging system comprises inner and outer air intake pipelines; the exhaust system comprises an exhaust gas separation ring and two exhaust channels, the exhaust gas separation ring divides the inner top area of ​​the furnace body into an inner exhaust gas area and an outer exhaust gas area respectively connected to the two exhaust channels; the upper barrier ring and the top of the heat preservation device are both provided with inner and outer connecting channels. The chemical vapor deposition furnace realizes heterogeneous or dual-component chemical vapor deposition processing on the inner and outer sides of the cylindrical workpiece at the same time, thereby reducing production energy consumption and improving production efficiency; and the exhaust gas can be separated and discharged, thereby improving safety.

Description

Technical Field

[0001] The invention relates to the technical field of chemical vapor deposition, in particular to a chemical vapor deposition furnace for an inner and outer double-component cylindrical workpiece. Background Art

[0002] For some aerospace components or some carbon fiber reinforced composite components, such as cylindrical workpieces (one end or both ends open) such as ceramic-based composite crucibles for polysilicon growth, the working environment on the inside and outside is inconsistent. For example, one side of the component is in a high-temperature oxidation or high-temperature corrosion (such as Si vapor) environment, while the other side is in an oxygen-isolated environment. In order to ensure the mechanical properties and thermal vibration resistance of the component, the high-temperature oxidation side usually needs to deposit SiC coating and a certain thickness of SiC densification, while the oxygen-isolated side usually needs to deposit pyrolytic carbon. This kind of cylindrical workpiece needs to deposit materials of different components on both sides, and the existing technology can usually only adopt a two-deposition process to achieve this. This requires two sets of equipment for processing, and two heating and cooling operations, which results in high production energy consumption, low production efficiency, and difficult quality control.

[0003] In addition, there are differences in the physical properties of two-component materials. For example, carbon fiber reinforced ceramic matrix composites have poorer toughness than carbon-carbon composites. And because the types of the workpiece matrix and the deposited material are different, their physical properties such as thermal expansion coefficient are quite different. After multiple heating and cooling, it is easy to cause the matrix and the deposited material to debond, affecting the quality of the workpiece. In addition, the tail gas of pyrolytic carbon deposition contains tar-like flammable and combustion-supporting substances, while the tail gas of silicon carbide deposition contains flammable and explosive substances such as silicon chloride. There is a risk of explosion when the two tail gases are mixed. Summary of the invention

[0004] The technical problem to be solved by the present invention is that in the prior art, inner and outer two-component workpieces can only be produced by a two-deposition processing technology, resulting in high energy consumption and low production efficiency. A chemical vapor deposition furnace for inner and outer two-component cylindrical workpieces is provided, which can simultaneously perform chemical vapor deposition processing on the inner and outer sides of the cylindrical workpiece.

[0005] The technical solution to the technical problem of the present invention is: construct a chemical vapor deposition furnace for an inner and outer double-component cylindrical workpiece, including a chemical vapor deposition furnace for an inner and outer double-component cylindrical workpiece, including a furnace body, a heat preservation device, a heater arranged in the heat preservation device, a process gas filling system and an exhaust system, wherein a closed deposition chamber is arranged in the heat preservation device; it also includes a workpiece support seat arranged at the bottom of the deposition chamber for supporting and positioning the cylindrical workpiece, and an upper barrier ring arranged between the open end of the top of the cylindrical workpiece and the top of the heat preservation device; the upper barrier ring and the cylindrical workpiece separate the deposition chamber into an outer chamber area and an inner chamber area; the process gas filling system includes a gas filling system for supplying gas to the inner chamber area; the ... The inner air inlet pipeline for filling the process gas into the inner area of ​​the deposition chamber and the outer air inlet pipeline for filling the process gas into the outer area of ​​the deposition chamber; the exhaust system includes an exhaust gas separation ring arranged on the top of the inner side of the furnace body and two exhaust channels arranged on the top of the furnace body, the exhaust gas separation ring divides the inner top area of ​​the furnace body into an inner exhaust gas area and an outer exhaust gas area respectively connected to the two exhaust channels; the upper barrier ring and the top of the insulation device are both provided with an inner connecting channel connecting the inner area of ​​the deposition chamber to the inner exhaust gas area, and an outer connecting channel connecting the outer area of ​​the deposition chamber to the outer exhaust gas area.

[0006] Furthermore, the upper barrier ring is provided with a barrier bottom plate matched with the inner top of the insulation device, and an annular barrier boss protruding from the barrier bottom plate toward the open end at the top of the cylindrical workpiece; the inner connecting channel includes barrier inner through holes evenly distributed circumferentially on the barrier bottom plate and located on the inner side of the barrier boss, and the outer connecting channel includes barrier outer through holes evenly distributed circumferentially on the barrier bottom plate and located on the outer side of the barrier boss; the upper barrier ring can be reliably positioned between the inner top of the insulation device and the open end at the top of the cylindrical workpiece, reliably separating the deposition chamber into inner and outer chamber areas, and can be respectively connected with the inner and outer exhaust gas areas.

[0007] Furthermore, the internal connecting channel includes an insulating inner through hole arranged at the top of the insulation device and connected to the blocking inner through hole, and the external connecting channel includes an insulating outer through hole arranged at the top of the insulation device and connected to the blocking outer through hole; to ensure that the inner and outer chamber areas can be connected to the inner and outer exhaust gas areas respectively.

[0008] Furthermore, the insulation device includes a circumferential insulation layer arranged on the inner circumferential side wall of the furnace body, a bottom insulation layer arranged on the inner bottom of the furnace body, an inner insulation tube arranged in the central area of ​​the furnace body, and an upper insulation ring arranged on the top of the inner insulation tube.

[0009] Furthermore, an isolation tube is provided on the inner side of the circumferential insulation layer, and the heater is arranged between the circumferential insulation layer and the isolation tube; the circumferential insulation layer, the bottom insulation layer, the inner insulation tube and the upper insulation ring are combined to form the deposition chamber; the upper insulation ring includes a horizontal rib ring located between the upper barrier ring and the exhaust gas separation ring and a vertical rib ring located between the top of the inner insulation tube and the inner top of the furnace body; so as to prevent the process gas from contaminating the heater.

[0010] Furthermore, the two exhaust channels are arranged side by side on the side of the top of the furnace body, and an exhaust boundary plate is provided between the two exhaust channels; the exhaust gas separation ring includes an annular body arranged between the inner top of the furnace body and the horizontal rib ring of the upper insulation ring, and an annular convex rib extending from the outer side of the annular body to the inner circumferential side of the furnace body, the annular convex rib is flush with the exhaust boundary plate, and a portion of the annular body located above the annular convex rib is evenly distributed with a plurality of connecting holes; so that the exhaust gas separation ring can completely divide the area between the upper insulation ring and the inner top of the furnace body into two exhaust gas areas, and respectively connect with the two exhaust channels.

[0011] Furthermore, it also includes a connecting ring that connects the inner insulation tube and the upper insulation ring to the top of the furnace body, so that the inner insulation tube and the upper insulation ring are reliably positioned in the furnace body.

[0012] Furthermore, the inner air inlet pipeline includes an air inlet nozzle arranged on the wall and bottom of the inner insulation cylinder, a controller connected to an external gas source, and an air duct connecting the air inlet nozzle and the controller. The controller can independently control the process gas entering the inner area of ​​the deposition chamber, thereby realizing the control of the deposition process inside the cylindrical workpiece.

[0013] Furthermore, the outer air inlet pipeline includes an air inlet nozzle arranged on the isolation tube and the bottom insulation layer, a controller connected to an external air source, and an air duct connecting the air inlet nozzle and the controller. The controller can individually control the process gas entering the outer chamber area of ​​the deposition chamber, thereby realizing the control of the deposition process on the outside of the cylindrical workpiece.

[0014] Furthermore, the cylindrical workpiece is open at both ends and also includes a lower barrier ring arranged between the open end of the bottom of the cylindrical workpiece and the inner bottom of the insulation device; the upper and lower barrier rings and the cylindrical workpiece separate the deposition chamber into an outer chamber area and an inner chamber area; so that the equipment is suitable for cylindrical workpieces with open ends at both ends; thereby increasing the scope of application of the equipment.

[0015] The chemical vapor deposition furnace for the inner and outer dual-component cylindrical workpiece according to the present invention has the following beneficial effects: by arranging an upper barrier ring between the top open end of the cylindrical workpiece and the top of the insulation device, the upper barrier ring and the cylindrical workpiece are combined to separate the deposition chamber into an outer chamber area and an inner chamber area; by arranging a process gas charging system including an inner air inlet pipeline and an outer air inlet pipeline, different process gases are respectively charged into the outer chamber area and the inner chamber area of ​​the deposition chamber, thereby achieving chemical vapor deposition processing on the inner and outer sides of the cylindrical workpiece at the same time, thereby reducing production energy consumption and improving production efficiency.

[0016] In addition, by setting up an exhaust system including an exhaust gas separation ring and an exhaust channel, the top area on the inner side of the furnace body is divided into an inner exhaust area and an outer exhaust area, which are connected to the inner and outer areas of the deposition chamber through inner and outer connecting channels respectively, thereby separating the exhaust gas generated by the deposition on the inner and outer sides of the cylindrical workpiece and separately leading them out of the furnace body, ensuring that the exhaust gas will not mix and cause safety hazards. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of a preferred embodiment of a chemical vapor deposition furnace for an inner and outer dual-component cylindrical workpiece according to the present invention;

[0018] Figure 2 Shown Figure 1 A magnified view of part I;

[0019] Figure 3 The figure is a three-dimensional view of the upper barrier ring in the preferred embodiment of the chemical vapor deposition furnace for the inner and outer dual-component cylindrical workpiece of the present invention;

[0020] Figure 4 It is a cross-sectional view of an upper barrier ring in a preferred embodiment of a chemical vapor deposition furnace for an inner and outer dual-component cylindrical workpiece according to the present invention;

[0021] Figure 5 Shown is a structural schematic diagram of another embodiment of the chemical vapor deposition furnace for inner and outer dual-component cylindrical workpieces of the present invention. DETAILED DESCRIPTION

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0023] It should also be noted that the directions or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limiting the present invention.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0025] like Figure 1 , 2 As shown in Figures 3, 4 and 5, in the preferred embodiment of the chemical vapor deposition furnace for the inner and outer dual-component cylindrical workpiece of the present invention, it mainly includes a furnace body 10, a heat preservation device, a heater 1 arranged in the heat preservation device, an upper barrier ring 30, a process gas filling system 40 and an exhaust system 50. In this preferred embodiment, the cylindrical workpiece 2 is open at one end, including a cylinder wall 2a and a cylinder bottom 2b. Among them, a closed deposition chamber 3 is provided in the heat preservation device, and a workpiece support seat 4 is provided at the bottom of the deposition chamber 3, and the workpiece support seat 4 is used to support the cylindrical workpiece 2. The upper barrier ring 30 is arranged between the top open end of the cylindrical workpiece 2 and the top of the heat preservation device. The top open end of the cylindrical workpiece 2 in this embodiment is the top of the cylindrical workpiece wall 2a. The upper barrier ring 30 and the cylindrical workpiece 2 separate the deposition chamber 3 into an outer chamber area 3a and an inner chamber area 3b. The process gas charging system 40 includes an inner air inlet pipeline 41 and an outer air inlet pipeline 42. The inner air inlet pipeline 41 charges the process gas into the inner area 3b of the deposition chamber, and the outer air inlet pipeline 42 charges the process gas into the outer area 3a of the deposition chamber. The exhaust system 50 includes an exhaust gas separation ring 51 and two exhaust channels 52. The exhaust gas separation ring 51 is arranged on the inner top of the furnace body 10, and the two exhaust channels 52 are arranged on the top of the furnace body 10. The exhaust gas separation ring 51 divides the area between the inner top of the furnace body 10 and the top of the insulation device into an inner exhaust gas area 13a and an outer exhaust gas area 13b. The inner and outer exhaust gas areas 13a and 13b are connected to the two exhaust channels 52 respectively. The upper barrier ring 30 and the top of the insulation device are both provided with an inner connecting channel 5 connecting the inner area 3b of the deposition chamber to the inner exhaust gas area 13a. The upper barrier ring 30 and the top of the insulation device are both provided with an outer connecting channel 6 connecting the outer area 3a of the deposition chamber to the outer exhaust gas area 13b.

[0026] In this preferred embodiment, the furnace body 10 is preferably configured to include an upper furnace cover 11 and a furnace shell 12 , the furnace cover is sealed at the top of the furnace shell 12 through a locking device, and the heat preservation device is disposed in the furnace shell 12 .

[0027] In this preferred embodiment, the heat preservation device is preferably provided to include a circumferential heat preservation layer 21, a bottom heat preservation layer 22, an inner heat preservation tube 23 and an upper heat preservation ring 24. The circumferential heat preservation layer 21 is provided on the circumferential side wall of the inner side of the furnace body 10. Specifically, the circumferential heat preservation layer 21 can be attached to the inner side wall of the furnace shell 12; the bottom heat preservation layer 22 is provided at the inner bottom of the furnace body 10; the inner heat preservation tube 23 is provided in the central area of ​​the furnace body 10, including a heat preservation tube wall 23a and a heat preservation tube bottom 23b, and the upper heat preservation ring 24 is provided at the top of the inner heat preservation tube 23. Preferably, an isolation tube 7 is provided inside the circumferential heat preservation layer 21, and the heater 1 is provided between the circumferential heat preservation layer 21 and the isolation tube 7. Specifically, an annular receiving groove 21a matching with the heater 1 can be provided inside the circumferential heat preservation layer 21, the heater 1 is provided in the receiving groove 21a, and the isolation tube 7 covers the open part of the receiving groove 21a. The isolation tube 7, the bottom insulation layer 22, the inner insulation tube 23 and the upper insulation ring 24 are combined to form the above-mentioned closed deposition chamber 3. The cylindrical workpiece 2 is located in the deposition chamber 3. Specifically, the cylinder wall 2a of the cylindrical workpiece is located between the isolation tube 7 and the inner insulation tube 23, and the cylinder bottom 2b of the cylindrical workpiece is supported and positioned between the bottom insulation layer 22 and the insulation tube bottom 23b by the workpiece support seat 4.

[0028] In this preferred embodiment, the upper insulation ring 24 includes a horizontal rib ring 24a and a vertical rib ring 24b which are perpendicular to each other. The horizontal rib ring 24a is located between the upper barrier ring 30 and the tail gas separation ring 51, and the vertical rib ring 24b is located between the top of the inner insulation tube 23 and the inner top of the furnace body 10, that is, the vertical rib ring 24b is located between the top of the inner insulation tube wall 23a and the inner top of the furnace body 10. It also includes a connecting ring 8 for connecting the inner insulation tube 23 and the upper insulation ring 24 to the top of the furnace body 10. Specifically, the vertical rib ring 24b of the upper insulation ring is flush with the inner wall of the inner insulation tube 23, and the connecting ring 8 is arranged on the inner side of the inner insulation tube 23. The connecting ring 8 is fixedly connected to the inner insulation tube wall 23a, the vertical rib ring 24b of the upper insulation ring, and the inner side of the upper furnace cover 11, respectively, so that the upper insulation ring 24 and the inner insulation tube 23 are positioned in the center area of ​​the furnace body 10.

[0029] In this preferred embodiment, the upper blocking ring 30 is preferably provided with a blocking bottom plate 31 and a blocking boss 32. The blocking bottom plate 31 is provided in an annular plate shape, and the blocking bottom plate 31 matches with the inner top of the heat preservation device, that is, the blocking bottom plate 31 of the upper blocking ring matches with the bottom surface of the horizontal rib ring 24a of the upper heat preservation ring. The blocking boss 32 is provided in an annular shape, and the blocking boss 32 is provided on the bottom surface of the blocking bottom plate 31, and protrudes from the blocking bottom plate 31 toward the open end at the top of the cylindrical workpiece 2. An inner blocking through hole 5a is provided on the blocking bottom plate 31 at the inner side of the blocking boss 32, and an outer blocking through hole 6a is provided on the blocking bottom plate 31 at the outer side of the blocking boss 32; at the top of the heat preservation device, that is, at the horizontal rib ring 24a of the upper heat preservation ring, an inner heat preservation through hole 5b connected with the inner blocking through hole 5a is provided, and an outer heat preservation through hole 6b connected with the outer blocking through hole 6a is also provided. The inner communication channel 5 includes an isolating inner through hole 5a and a heat-insulating inner through hole 5b, and the outer communication channel 6 includes an isolating outer through hole 6a and a heat-insulating outer through hole 6b.

[0030] In this preferred embodiment, two exhaust channels 52 are arranged on the side of the top of the furnace body 10, that is, the side of the upper furnace cover 11. It is preferred that the two exhaust channels 52 are arranged side by side in the upper and lower parts, and an exhaust demarcation plate 52a is provided between the two exhaust channels 52. It is preferred that the tail gas separation ring 51 includes an annular body 51a and an annular convex rib 51b, wherein the annular body 51a is located between the inner top of the furnace body 10 and the upper insulation ring horizontal rib ring 24a, that is, between the bottom surface of the upper furnace cover 11 and the top surface of the upper insulation ring horizontal rib ring 24a; the annular convex rib 51b extends outward from the outer surface of the annular body 51a to the inner circumferential side of the furnace body 10 (that is, the inner wall of the upper furnace cover 11). The annular convex rib 51b is flush with the exhaust demarcation plate 52a, and preferably a plurality of connecting holes 51c are evenly arranged on the annular body 51a above the annular convex rib 51b. When the tail gas separation ring 51 is embedded in the bottom of the upper furnace cover 11, since the annular body 51a of the tail gas separation ring is located between the bottom surface of the upper furnace cover 11 and the top surface of the horizontal rib ring 24a of the upper insulation ring, the area between the bottom of the upper furnace cover 11 and the upper insulation ring 24 is divided into an inner ring area and an outer ring area; since the annular convex rib 51b of the tail gas separation ring is located between the annular body 51a and the inner circumferential side surface of the upper furnace cover 11, the outer ring area is further divided into an upper part and a lower part; since the annular convex rib 51b of the tail gas separation ring is flush with the exhaust boundary plate 52a, the upper part and the lower part of the outer ring area are respectively connected to the two exhaust channels 52; since a plurality of connecting holes 51c are provided on the annular body 51a, the upper part of the outer ring area is connected to the inner ring area. In this way, the upper part of the inner ring area and the outer ring area are combined to form the above-mentioned inner tail gas area 13a, and the lower part of the outer ring area forms the above-mentioned outer tail gas area 13b.

[0031] Two exhaust channels can also be set on the top surface of the upper furnace cover. In this case, the exhaust gas separation ring can be directly set as a ring-shaped body, and the area between the bottom of the upper furnace cover and the upper insulation ring is divided into an inner ring area and an outer ring area. The two exhaust channels are respectively connected to the inner ring area and the outer ring area, and the inner ring area and the outer ring area correspond to the above-mentioned inner exhaust gas area and outer exhaust gas area respectively.

[0032] In this preferred embodiment, the inner air inlet pipeline 41 includes an air inlet nozzle 43 provided on the inner heat-insulating cylinder wall 23a and the heat-insulating cylinder bottom 23b, a controller 44 connected to an external gas source, and an air guide pipe 45 connecting the air inlet nozzle 43 and the controller 44. The controller 44 can individually control the process gas entering the inner chamber area 3b of the deposition chamber to achieve control of the deposition process inside the cylindrical workpiece 2. Specifically, multiple controllers 44 can also be provided to control the inner circumferential air inlet pipeline 41a and the inner bottom air inlet pipeline 41b respectively, wherein the inner circumferential air inlet pipeline 41a corresponds to the air inlet nozzle 43 provided on the inner heat-insulating cylinder wall 23a, and the inner bottom air inlet pipeline 41b corresponds to the air inlet nozzle 43 provided on the heat-insulating cylinder bottom 23b.

[0033] In this preferred embodiment, the outer air inlet pipeline 42 includes an air inlet nozzle 43 provided on the isolation tube 7 and the bottom insulation layer 22, a controller 44 connected to an external gas source, and an air guide pipe 45 connecting the air inlet nozzle 43 and the controller 44. The controller 44 can individually control the process gas entering the outer chamber area 3a of the deposition chamber to achieve control of the deposition process on the outer side of the cylindrical workpiece 2. Specifically, multiple controllers 44 can also be provided to control the outer circumferential air inlet pipeline 42a and the outer bottom air inlet pipeline 42b, respectively, wherein the outer circumferential air inlet pipeline 42a corresponds to the air inlet nozzle 43 provided on the isolation tube 7, and the outer bottom air inlet pipeline 42b corresponds to the air inlet nozzle 43 provided on the bottom insulation layer 22.

[0034] like Figure 5 As shown, in another embodiment of the chemical vapor deposition furnace for the inner and outer dual-component cylindrical workpiece 2 of the present invention, the cylindrical workpiece 2 is open at both ends, and the chemical vapor deposition furnace also includes a furnace body 10, a heat preservation device, a heater 1 arranged in the heat preservation device, an upper barrier ring 30, a process gas charging system 40 and an exhaust system 50; and also includes a lower barrier ring 60. Among them, a closed deposition chamber 3 is also arranged in the heat preservation device, and at this time, a workpiece support seat can be arranged at the bottom of the deposition chamber 3, or it can not be arranged.

[0035] The upper barrier ring 30 is arranged between the top open end of the cylindrical workpiece 2 and the top of the heat preservation device. In this embodiment, the top open end of the cylindrical workpiece 2 is the top of the cylindrical workpiece wall 2a. The lower barrier ring 60 is arranged between the bottom open end of the cylindrical workpiece 2 and the inner bottom of the heat preservation device, that is, the lower barrier ring 60 is located between the bottom end of the cylindrical workpiece wall 2a and the top surface of the bottom heat preservation layer 22. The upper barrier ring 30, the lower barrier ring 60 and the cylindrical workpiece 2 separate the deposition chamber 3 into an outer chamber area 3a and an inner chamber area 3b.

[0036] The process gas charging system 40 is set according to the preferred embodiment, and includes an inner air inlet pipeline 41 and an outer air inlet pipeline 42. The inner air inlet pipeline 41 charges the process gas into the inner chamber area 3b of the deposition chamber, and the outer air inlet pipeline 42 charges the process gas into the outer chamber area 3a of the deposition chamber; specifically, the inner air inlet pipeline 41 includes an inner circumferential air inlet pipeline 41a and an inner bottom air inlet pipeline 41b, and the outer air inlet pipeline 42 includes an outer circumferential air inlet pipeline 42a and an outer bottom air inlet pipeline 42b. The inner bottom air inlet pipeline 41b and the outer bottom air inlet pipeline 42b are controlled to stop working by the controller 44, and different process gases are respectively passed into the inner circumferential air inlet pipeline 41a and the outer circumferential air inlet pipeline 42a.

[0037] The exhaust system 50 is arranged with reference to the preferred embodiment, and includes an exhaust gas separation ring 51 and two exhaust channels 52. The exhaust gas separation ring 51 is arranged at the inner top of the furnace body 10, and the two exhaust channels 52 are arranged at the top of the furnace body 10; the exhaust gas separation ring 51 divides the inner top area of ​​the furnace body 10 into an inner exhaust gas area 13a and an outer exhaust gas area 13b, and the inner and outer exhaust gas areas 13a and 13b are respectively connected to the two exhaust channels 52. The upper barrier ring 30 and the top of the heat preservation device are both provided with an inner connecting channel 5 connecting the inner area 3b of the deposition chamber to the inner exhaust gas area 13a, and the upper barrier ring 30 and the top of the heat preservation device are both provided with an outer connecting channel 6 connecting the outer area 3a of the deposition chamber to the outer exhaust gas area 13b.

[0038] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work, any modifications, equivalent substitutions, improvements, etc. made should be included in the protection scope of the present invention.

Claims

1. A chemical vapor deposition furnace for inner and outer dual-component cylindrical workpieces, comprising a furnace body, a heat preservation device, a heater arranged in the heat preservation device, a process gas filling system and an exhaust system, characterized in that: The heat preservation device is provided with a sealed deposition chamber; it also includes a workpiece support seat arranged at the bottom of the deposition chamber for supporting and positioning the cylindrical workpiece, and an upper blocking ring arranged between the open end of the top of the cylindrical workpiece and the top of the heat preservation device; the upper blocking ring and the cylindrical workpiece separate the deposition chamber into an outer chamber area and an inner chamber area; The process gas filling system comprises an inner gas inlet pipeline for filling the process gas into the inner region of the deposition chamber and an outer gas inlet pipeline for filling the process gas into the outer region of the deposition chamber; The exhaust system comprises an exhaust gas separation ring arranged at the top of the inner side of the furnace body and two exhaust channels arranged at the top of the furnace body, wherein the exhaust gas separation ring divides the top area of ​​the inner side of the furnace body into an inner exhaust gas area and an outer exhaust gas area respectively connected to the two exhaust channels; The upper blocking ring and the top of the heat preservation device are both provided with an internal connecting passage connecting the inner area of ​​the deposition chamber to the inner exhaust gas area, and an external connecting passage connecting the inner area of ​​the deposition chamber to the outer exhaust gas area.

2. The chemical vapor deposition furnace for inner and outer dual-component cylindrical workpieces according to claim 1, characterized in that: The upper barrier ring is provided with a barrier bottom plate matched with the inner top of the heat preservation device, and an annular barrier boss protruding from the barrier bottom plate toward the open end of the top of the cylindrical workpiece; the inner connecting channel includes barrier inner through holes evenly distributed circumferentially on the barrier bottom plate and located on the inner side of the barrier boss, and the outer connecting channel includes barrier outer through holes evenly distributed circumferentially on the barrier bottom plate and located on the outer side of the barrier boss.

3. The chemical vapor deposition furnace for inner and outer dual-component cylindrical workpieces according to claim 2, characterized in that: The inner communicating channel comprises an inner insulating through hole arranged at the top of the insulating device and communicating with the inner blocking through hole, and the outer communicating channel comprises an outer insulating through hole arranged at the top of the insulating device and communicating with the outer blocking through hole.

4. The chemical vapor deposition furnace for inner and outer dual-component cylindrical workpieces according to claim 2, characterized in that: The insulation device includes a circumferential insulation layer arranged on the inner circumferential side wall of the furnace body, a bottom insulation layer arranged on the inner bottom of the furnace body, an inner insulation tube arranged in the central area of ​​the furnace body, and an upper insulation ring arranged on the top of the inner insulation tube.

5. The chemical vapor deposition furnace for inner and outer dual-component cylindrical workpieces according to claim 4, characterized in that: An isolation tube is provided on the inner side of the circumferential insulation layer, and the heater is arranged between the circumferential insulation layer and the isolation tube; the isolation tube, the bottom insulation layer, the inner insulation tube and the upper insulation ring are combined to form the deposition chamber; the upper insulation ring includes a horizontal rib ring located between the upper barrier ring and the exhaust gas separation ring and a vertical rib ring located between the top of the inner insulation tube and the inner top of the furnace body.

6. The chemical vapor deposition furnace for inner and outer dual-component cylindrical workpieces according to claim 4, characterized in that: The two exhaust channels are arranged side by side on the side of the top of the furnace body, and an exhaust boundary plate is provided between the two exhaust channels; the exhaust gas separation ring includes an annular body arranged between the top of the inner side of the furnace body and the horizontal rib ring of the upper insulation ring, and an annular convex rib extending from the outer side of the annular body to the inner circumferential side of the furnace body, the annular convex rib is flush with the exhaust boundary plate, and a plurality of connecting holes are evenly distributed on the portion of the annular body located above the annular convex rib.

7. The chemical vapor deposition furnace for inner and outer dual-component cylindrical workpieces according to claim 4, characterized in that: It also includes a connecting ring for connecting the inner insulation tube and the upper insulation ring to the top of the furnace body.

8. The chemical vapor deposition furnace for inner and outer dual-component cylindrical workpieces according to claim 4, characterized in that: The inner air intake pipeline includes an air intake nozzle arranged on the wall and bottom of the inner heat-insulating cylinder, a controller connected to an external air source, and an air guide pipe connecting the air intake nozzle and the controller.

9. The chemical vapor deposition furnace for inner and outer dual-component cylindrical workpieces according to claim 5, characterized in that: The outer air intake pipeline includes an air intake nozzle arranged on the isolation tube and the bottom insulation layer, a controller connected to an external air source, and an air guide pipe connecting the air intake nozzle and the controller.

10. The chemical vapor deposition furnace for inner and outer dual-component cylindrical workpieces according to claim 1, characterized in that: The cylindrical workpiece is open at both ends and also includes a lower barrier ring arranged between the open end of the bottom of the cylindrical workpiece and the inner bottom of the insulation device; the upper and lower barrier rings and the cylindrical workpiece separate the deposition chamber into an outer chamber area and an inner chamber area.

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