CN220284212U - Gas diffusion device and vapor deposition equipment - Google Patents

Abstract

A gas diffusion device and vapor deposition equipment relate to the technical field of vapor deposition. The gas diffusion device comprises a diffusion cylinder which is arranged in an inlet channel of a reaction cavity in a rotating mode, a plurality of diffusion holes and rotary driving parts are formed in the inner wall of the diffusion cylinder, and gas enters the diffusion cylinder through the diffusion holes and then impacts the rotary driving parts so that the diffusion cylinder rotates. This gas diffusion device is through setting up rotary drive portion at the inner wall of diffusion section of thick bamboo, utilizes rotary drive portion to make the inner wall of diffusion section of thick bamboo present the rugged state, increases with the frictional force between the gas, and then realizes the rotation of diffusion section of thick bamboo, simple structure need not to additionally set up the rotatory device of drive diffusion section of thick bamboo, moreover, the diffusion section of thick bamboo receives the gas to assault the back and rotates by oneself and can effectively solve the gas backfill problem.

Description

Gas diffusion device and vapor deposition equipment

Technical Field

The utility model relates to the technical field of vapor deposition, in particular to a gas diffusion device and vapor deposition equipment.

Background

In the semiconductor wafer packaging manufacturing process, chemical vapor deposition is a chemical technology, and the technology mainly utilizes one or more vapor compounds or simple substances containing film elements to perform chemical reaction on the surface of a substrate to generate a film. The deposition process is mainly performed in a cavity, and the pressure difference between the air source end and the cavity is large because the air pressure conveyed by the air source end is several atmospheres and the cavity is vacuum.

In order to prevent the wafer from being adversely affected by the back-flowing gas, a gas diffusion device is required to be provided in the chamber to reduce the gas flow strength and change the gas flow direction. However, the existing gas diffusion device cannot realize gas spin coating, and still has the problem of gas backfill.

Disclosure of Invention

The utility model aims to provide a gas diffusion device and vapor deposition equipment, which can solve the problem of gas backfill.

Embodiments of the present utility model are implemented as follows:

the embodiment of the utility model provides a gas diffusion device, which comprises a diffusion cylinder rotatably arranged in an inlet channel of a reaction cavity, wherein a plurality of diffusion holes and rotary driving parts are arranged on the inner wall of the diffusion cylinder, and gas enters the diffusion cylinder through the diffusion holes and then impacts the rotary driving parts so as to enable the diffusion cylinder to rotate.

Optionally, the rotation driving part is a groove or a protrusion, and the plurality of grooves or the plurality of protrusions are respectively located at the side surfaces of the diffusion holes.

Optionally, the diffusion holes comprise a first diffusion hole group and a plurality of second diffusion hole groups distributed at intervals along the circumferential direction of the diffusion barrel, and the first diffusion hole group is positioned between two adjacent second diffusion hole groups; the first diffusion hole group comprises at least two rows of first diffusion holes which are distributed at intervals along the circumferential direction of the diffusion cylinder, and each row of first diffusion holes is distributed at intervals along the axial direction of the diffusion cylinder; the second diffusion hole group comprises a plurality of second diffusion holes which are distributed at intervals along the axial direction of the diffusion cylinder; and a plurality of rotary driving parts are arranged between two adjacent second diffusion hole groups and/or between the adjacent first diffusion hole groups and the second diffusion hole groups, and the rotary driving parts are distributed at intervals along the axial direction of the diffusion cylinder.

Alternatively, the plurality of rotary driving portions are uniformly distributed along the axial direction of the diffusion cylinder, and the adjacent two rows of rotary driving portions correspond to each other in circumferential position along the diffusion cylinder.

Optionally, the diffusion cylinder comprises a first diffusion cylinder and a second diffusion cylinder with an opening at one end, the first diffusion cylinder and the second diffusion cylinder are coaxially arranged, the end part of the first diffusion cylinder stretches into the second diffusion cylinder and is connected with the cylinder bottom of the second diffusion cylinder, the first diffusion cylinder is positioned in the inlet channel, the diameter of the first diffusion cylinder is smaller than that of the inlet channel, the second diffusion cylinder is positioned at the end part of the inlet channel, and the diameter of the second diffusion cylinder is larger than or equal to that of the inlet channel; the first diffusion hole group and the second diffusion hole group are positioned on the first diffusion barrel, the diffusion barrel further comprises a third diffusion hole group arranged on the second diffusion barrel, and the third diffusion hole group comprises a plurality of third diffusion holes which are distributed at intervals along the circumferential direction of the second diffusion barrel.

Optionally, the first diffusion holes and the second diffusion holes are uniformly distributed along the axial direction of the first diffusion barrel, and the third diffusion holes are uniformly distributed along the circumferential direction of the second diffusion barrel.

Optionally, the device further comprises a fixing plate, the end part of the diffusion barrel is provided with a mounting flange, the fixing plate is provided with a mounting groove for accommodating the mounting flange, the outer wall of the diffusion barrel is provided with a sealing ring, the sealing ring is located on one side, away from the mounting groove, of the mounting flange, the sealing ring is fixedly connected with the fixing plate, and the fixing plate is used for being connected with the outer wall of the reaction cavity.

Optionally, one end of the diffusion cylinder, provided with the mounting flange, is provided with an opening, and the bottom of the mounting groove is provided with a heat dissipation hole penetrating through the fixed disc, and the heat dissipation hole corresponds to the opening position of the diffusion cylinder.

Optionally, a plurality of first air inlets surrounding the installation groove are arranged on the fixed disc, a plurality of second air inlets corresponding to the first air inlets one by one are arranged on the sealing ring, and gas enters the diffusion cylinder through the first air inlets, the second air inlets and the diffusion holes.

The embodiment of the utility model also provides vapor deposition equipment, which comprises a cavity and the gas diffusion device rotationally arranged in the inlet channel of the cavity.

The beneficial effects of the embodiment of the utility model include:

the gas diffusion device provided by the embodiment of the utility model comprises a diffusion cylinder which is rotatably arranged in an inlet channel of a reaction cavity, wherein the inner wall of the diffusion cylinder is provided with a plurality of diffusion holes and a rotary driving part, and gas enters the diffusion cylinder through the diffusion holes and then impacts the rotary driving parts so as to enable the diffusion cylinder to rotate. Above-mentioned gas diffusion device, through setting up rotary drive portion at the inner wall of diffusion section of thick bamboo, utilize rotary drive portion to make the inner wall of diffusion section of thick bamboo present the rugged state, increase with the gaseous frictional force between, and then realize the rotation of diffusion section of thick bamboo, simple structure need not to additionally set up the rotatory device of drive diffusion section of thick bamboo, moreover, the diffusion section of thick bamboo receives the gas to assault the back and rotates by oneself and can effectively solve the gas and backfill the problem.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present utility model and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of a gas diffusion apparatus according to an embodiment of the present utility model;

fig. 2 is an exploded view of a gas diffusion device according to an embodiment of the present utility model.

Icon: 100-gas diffusion means; 110-a diffusion cylinder; 111-a first diffusion cylinder; 1111-groove; 1112-first diffusion holes; 1113-second diffusion holes; 112-a second diffusion cylinder; 1121-third diffusion holes; 113-mounting flanges; 120-fixing a disc; 121-a first air inlet hole; 122-heat dissipation holes; 123-first connection holes; 124-mounting slots; 130-a sealing ring; 131-a second air inlet; 132-a second connection hole; 140-screws.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present utility model more apparent, the technical solutions of the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model, and it is apparent that the described embodiments are some embodiments of the present utility model, but not all embodiments of the present utility model. The components of the embodiments of the present utility model generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the utility model, as presented in the figures, is not intended to limit the scope of the utility model, as claimed, but is merely representative of selected embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.

In the description of the present utility model, it should be noted that, directions or positional relationships indicated by terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., are directions or positional relationships based on those shown in the drawings, or are directions or positional relationships conventionally put in use of the inventive product, are merely for convenience of describing the present utility model and simplifying the description, and are not indicative or implying that the apparatus or element to be referred to must have a specific direction, be constructed and operated in a specific direction, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," "third," and the like are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance.

In the description of the present utility model, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be connected between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

Referring to fig. 1 and 2 in combination, an embodiment of the present application provides a gas diffusion apparatus 100, which includes a diffusion cylinder 110 rotatably disposed in an inlet channel of a reaction chamber, wherein a plurality of diffusion holes and a rotation driving portion are disposed on an inner wall of the diffusion cylinder 110, and gas enters the diffusion cylinder 110 through the diffusion holes and then impacts the rotation driving portion to rotate the diffusion cylinder 110.

The gas diffusion apparatus 100 includes a diffusion cylinder 110, and the diffusion cylinder 110 is rotatably disposed at an inlet passage of a reaction chamber, that is, the diffusion cylinder 110 is fixed in the inlet passage of the reaction chamber, but the diffusion cylinder 110 is rotatable in the inlet passage after being driven. The inner wall of the diffusion cylinder 110 is provided with a plurality of rotation driving parts and diffusion holes penetrating the diffusion cylinder 110, and the diffusion holes are used for increasing the fluidity of the gas so as to realize the circulation of the gas in the diffusion cylinder 110. The external gas enters the diffusion cylinder 110 through the diffusion holes, and the impact rotation driving part rotates the diffusion cylinder 110, so that the gas is rotationally diffused into the reaction cavity when the diffusion cylinder 110 rotates.

In the present embodiment, the structure of the rotation driving part is not limited as long as it can rotate the diffusion cylinder 110 when being impacted by gas.

Above-mentioned gas diffusion device 100, through setting up rotary drive portion at the inner wall of diffusion section of thick bamboo 110, utilize rotary drive portion to make the inner wall of diffusion section of thick bamboo 110 present the rugged state, increase with the frictional force between the gas, and then realize the rotation of diffusion section of thick bamboo 110, simple structure need not additionally to set up the rotatory device of drive diffusion section of thick bamboo 110, moreover, diffusion section of thick bamboo 110 receive the back autogenous rotation of gas impact can effectively solve the gas backfill problem.

Alternatively, in one implementation manner of the embodiment of the present utility model, the rotation driving portion is a groove 1111 or a protrusion, and the plurality of grooves 1111 or the plurality of protrusions are located at sides of the diffusion hole, respectively.

The rotation driving part is a groove 1111 or a protrusion arranged around the diffusion hole, and the groove 1111 or the protrusion makes the inner wall of the diffusion cylinder 110 uneven, so that the friction force between the diffusion cylinder and the gas is increased, and the diffusion cylinder 110 can rotate by itself after the gas is introduced. In addition, the groove 1111 and the protrusion are easy to process, and the cost can be reduced.

Optionally, in one implementation manner of the embodiment of the present utility model, the diffusion holes include a first diffusion hole group and a plurality of second diffusion hole groups distributed at intervals along a circumferential direction of the diffusion barrel 110, and the first diffusion hole group is located between two adjacent second diffusion hole groups; the first diffusion hole group includes at least two rows of first diffusion holes 1112 that are spaced apart along the circumferential direction (circumferential direction) of the diffusion cylinder 110, each row of first diffusion holes 1112 being spaced apart along the axial direction (axial direction) of the diffusion cylinder 110; the second diffusion hole group includes a plurality of second diffusion holes 1113 spaced apart along the axial direction of the diffusion cylinder 110; a plurality of rotation driving parts are arranged between two adjacent second diffusion hole groups and/or between the adjacent first diffusion hole groups and the second diffusion hole groups, and the rotation driving parts are distributed at intervals along the axial direction of the diffusion cylinder 110.

The first diffusion hole group is a row of holes, and includes at least two rows of first diffusion holes 1112 distributed at intervals along the circumferential direction of the diffusion barrel 110, and no rotating diffusion part is arranged between two adjacent first diffusion holes 1112 so as to reduce the interval between the first diffusion holes 1112, thereby improving the fluidity of the gas in the diffusion barrel 110. The second diffusion hole group is a single row hole, and a rotation driving part is arranged between two adjacent second diffusion holes 1113 or between the second diffusion holes 1113 and the first diffusion holes 1112 so as to realize rotation diffusion of gas.

The number of the first diffusion hole groups is at least one, and the first diffusion hole groups can be reasonably arranged according to actual requirements by a person skilled in the art. If the number of the first diffusion hole groups is two or more, preferably, the two or more first diffusion hole groups are arranged at intervals, and at least one second diffusion hole group is arranged between two adjacent first diffusion hole groups.

Alternatively, in one possible implementation manner of the embodiment of the present utility model, the plurality of rotation driving portions are uniformly distributed along the axial direction of the diffusion barrel 110, and two adjacent rows of rotation driving portions correspond to each other along the circumferential position of the diffusion barrel 110.

The plurality of rotation driving parts distributed along the axial direction of the diffusion barrel 110 are arranged in a row, at least two rows of rotation driving parts are distributed at intervals along the circumferential direction of the diffusion barrel 110, and the positions of two adjacent rotation driving parts along the circumferential direction of the diffusion barrel 110 are the same in height. Preferably, at least two rows of rotation driving parts are equally spaced along the circumference of the diffusion cylinder 110, so that the stress of the diffusion cylinder 110 is more uniform.

Alternatively, in one possible implementation manner of the embodiment of the present utility model, the diffusion barrel 110 includes a first diffusion barrel 111 and a second diffusion barrel 112 with an opening, the first diffusion barrel 111 and the second diffusion barrel 112 are coaxially disposed, an end of the first diffusion barrel 111 extends into the second diffusion barrel 112 and is connected to a barrel bottom of the second diffusion barrel 112, the first diffusion barrel 111 is located in the inlet channel, a diameter of the first diffusion barrel 111 is smaller than a diameter of the inlet channel, the second diffusion barrel 112 is located at an end of the inlet channel, and a diameter of the second diffusion barrel 112 is greater than or equal to a diameter of the inlet channel; the first diffusion hole group and the second diffusion hole group are located on the first diffusion cylinder 111, and the diffusion cylinder 110 further includes a third diffusion hole group provided on the second diffusion cylinder 112, the third diffusion hole group including a plurality of third diffusion holes 1121 spaced apart in a circumferential direction of the second diffusion cylinder 112.

The first diffusion cylinder 111 is disposed inside the inlet passage, and the second diffusion cylinder 112 is disposed at an end of the inlet passage, and since the diameter of the second diffusion cylinder 112 is equal to or greater than that of the inlet passage, the second diffusion cylinder 112 can cover an end of the inlet passage connected to the reaction chamber, so that the gas entering the inlet passage and the inside of the first diffusion cylinder 111 can only exit into the reaction chamber through the third diffusion holes 1121 on the second diffusion cylinder 112. After entering the inlet channel, the gas enters the inside of the first diffusion cylinder 111 through the first diffusion hole 1112 and the second diffusion hole 1113 on the first diffusion cylinder 111, so as to drive the first diffusion cylinder 111 to rotate, and the second diffusion cylinder 112 is fixedly connected with the first diffusion cylinder 111, so that the second diffusion cylinder 112 also rotates along with the first diffusion cylinder 111, and the gas is diffused into the reaction cavity through the third diffusion hole 1121 to realize spin coating. The first diffusion hole group on the first diffusion cylinder 111 also increases the gas flow rate of the third diffusion holes 1121.

Optionally, in one possible manner of the embodiment of the present utility model, the plurality of first diffusion holes 1112 and the plurality of second diffusion holes 1113 are uniformly distributed along the axial direction of the first diffusion barrel 111, and the plurality of third diffusion holes 1121 are uniformly distributed along the circumferential direction of the second diffusion barrel 112, so as to improve the uniformity of gas diffusion.

If the number of the third diffusion hole groups is at least one, and if the number of the third diffusion hole groups is two or more, it is preferable that the two or more third diffusion hole groups are equally spaced along the axial direction of the second diffusion cylinder 112 to enhance the spin coating effect.

Optionally, in an implementation manner of the embodiment of the present utility model, the device further includes a fixing disc 120, an end portion of the diffusion barrel 110 is provided with a mounting flange 113, a mounting groove 124 for accommodating the mounting flange 113 is provided on the fixing disc 120, a sealing ring 130 is provided on an outer wall of the diffusion barrel 110, the sealing ring 130 is located on a side, away from the mounting groove 124, of the mounting flange 113, the sealing ring 130 is fixedly connected with the fixing disc 120, and the fixing disc 120 is used for being connected with an outer wall of the reaction chamber.

The diffusion cylinder 110 is rotatably disposed in the inlet passage by a fixed disk 120, and the fixed disk 120 is located outside the inlet passage. Specifically, the end of the diffusion cylinder 110 is provided with a mounting flange 113, and the mounting flange 113 is coaxially arranged with the diffusion cylinder 110 and has a diameter larger than that of the diffusion cylinder 110. The mounting flange 113 is mounted in the mounting groove 124 of the fixed disk 120, the diameter of the mounting groove 124 is equal to or slightly larger than that of the mounting flange 113, a sealing ring 130 is arranged on the other side of the mounting flange 113, the sealing ring 130 is sleeved on the outer wall of the diffusion cylinder 110, the sealing ring 130 is fixedly connected with the fixed disk 120, so that the mounting flange 113 is clamped and limited between the sealing ring 130 and the fixed disk 120, and the diffusion cylinder 110 is connected with the fixed disk 120 and can rotate relative to the fixed disk 120. When the gas diffusion device 100 is installed, the diffusion cylinder 110 is first inserted into the inlet channel, and then the fixing plate 120 is fixed on the outer wall of the reaction chamber.

Illustratively, the fixing plate 120 is provided with a plurality of first connecting holes 123 surrounding the mounting groove 124, the sealing ring 130 is provided with a plurality of second connecting holes 132 corresponding to the first connecting holes 123, and the fixing plate 120 and the sealing ring 130 pass through the first connecting holes 123 and the second connecting holes 132 through the screws 140 to achieve fixation.

Optionally, in an implementation manner of the embodiment of the present utility model, a plurality of first air inlets 121 surrounding the mounting groove 124 are provided on the fixed disk 120, a plurality of second air inlets 131 corresponding to the first air inlets 121 one by one are provided on the sealing ring 130, and air enters the diffusion cylinder 110 through the first air inlets 121, the second air inlets 131 and the diffusion holes to drive the diffusion cylinder 110 to rotate.

Optionally, in an implementation manner of the embodiment of the present utility model, an opening is formed at one end of the diffusion barrel 110 where the mounting flange 113 is disposed, a heat dissipation hole 122 penetrating through the fixing disc 120 is formed at a bottom of the mounting groove 124, and the heat dissipation hole 122 corresponds to the opening position of the diffusion barrel 110. The heat dissipation holes 122 and the openings are arranged to enable the inside of the diffusion cylinder 110 to be communicated with the outside, and heat in the diffusion cylinder 110 can be discharged through the openings and the heat dissipation holes 122 so as to avoid accumulation of heat in the diffusion cylinder 110.

In one embodiment, the assembly process of the gas diffusion device 100 is as follows: firstly, a sealing ring 130 is sleeved on a first diffusion cylinder 111, then a second diffusion cylinder 112 is welded on the first diffusion cylinder 111 by utilizing a welding process, then a mounting flange 113 at the bottom of the first diffusion cylinder 111 is placed in a mounting groove 124 of a fixed disk 120, the sealing ring 130 is connected with the fixed disk 120 by utilizing a screw 140, the mounted gas diffusion device 100 is plugged into a reaction cavity through the fixed disk 120, and the mounting on the outer wall of the reaction cavity is realized by utilizing the screw 140 on the fixed disk 120. The fixed disk 120 of the gas diffusion device 100 is provided with a heat dissipation hole 122 for dissipating heat and a first air inlet hole 121 for enabling gas to enter an inlet channel, the sealing ring 130 is provided with a second air inlet hole 131 communicated with the first air inlet hole 121, and after entering the inlet channel, the gas drives the second diffusion cylinder 112 to rotate, diffuse and spray through a groove 1111 in the first diffusion cylinder 111, and the first diffusion hole group and the second diffusion hole group on the first diffusion cylinder 111 achieve the purpose of increasing gas fluidity.

The present embodiment also provides a vapor deposition apparatus comprising a chamber and the gas diffusion device 100 of any one of the above rotatably disposed in an inlet passage of the chamber.

The vapor deposition apparatus includes the same structure and advantageous effects as the gas diffusion device 100 in the foregoing embodiment. The structure and the advantages of the gas diffusion device 100 are described in detail in the foregoing embodiments, and are not described herein.

The above description is only of the preferred embodiments of the present utility model and is not intended to limit the present utility model, but various modifications and variations can be made to the present utility model by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims (9)

1. The utility model provides a gas diffusion device which characterized in that, includes the diffusion section of thick bamboo that is used for rotating the setting in the entry passageway of reaction chamber, the inner wall of diffusion section of thick bamboo is equipped with a plurality of diffusion holes and rotation driving portion, and gas passes through the diffusion hole gets into behind the diffusion section of thick bamboo strike a plurality of rotation driving portion, so that the diffusion section of thick bamboo is rotatory, rotation driving portion is recess or arch, a plurality of recess or a plurality of protruding is located respectively the side of diffusion hole.

2. The gas diffusion device according to claim 1, wherein the diffusion holes comprise a first diffusion hole group and a plurality of second diffusion hole groups spaced apart along the circumferential direction of the diffusion cylinder, the first diffusion hole group being located between two adjacent second diffusion hole groups;

the first diffusion hole group comprises at least two rows of first diffusion holes which are distributed at intervals along the circumferential direction of the diffusion cylinder, and each row of first diffusion holes is distributed at intervals along the axial direction of the diffusion cylinder; the second diffusion hole group comprises a plurality of second diffusion holes which are distributed at intervals along the axial direction of the diffusion cylinder; and a plurality of rotary driving parts are arranged between two adjacent second diffusion hole groups and/or between the adjacent first diffusion hole groups and the second diffusion hole groups, and the rotary driving parts are distributed at intervals along the axial direction of the diffusion cylinder.

3. The gas diffusion device according to claim 2, wherein a plurality of the rotary drive portions are uniformly distributed in an axial direction of the diffusion cylinder, and adjacent two rows of the rotary drive portions correspond to each other in circumferential positions of the diffusion cylinder.

4. The gas diffusion device according to claim 2, wherein the diffusion cylinder comprises a first diffusion cylinder and a second diffusion cylinder with one end open, the first diffusion cylinder and the second diffusion cylinder are coaxially arranged, the end part of the first diffusion cylinder extends into the second diffusion cylinder and is connected with the cylinder bottom of the second diffusion cylinder, the first diffusion cylinder is positioned in the inlet channel, the diameter of the first diffusion cylinder is smaller than the diameter of the inlet channel, the second diffusion cylinder is positioned at the end part of the inlet channel, and the diameter of the second diffusion cylinder is larger than or equal to the diameter of the inlet channel;

the first diffusion hole group and the second diffusion hole group are positioned on the first diffusion barrel, the diffusion barrel further comprises a third diffusion hole group arranged on the second diffusion barrel, and the third diffusion hole group comprises a plurality of third diffusion holes which are distributed at intervals along the circumferential direction of the second diffusion barrel.

5. The gas diffusion device according to claim 4, wherein the plurality of first diffusion holes and the plurality of second diffusion holes are uniformly distributed in the axial direction of the first diffusion cylinder, respectively, and the plurality of third diffusion holes are uniformly distributed in the circumferential direction of the second diffusion cylinder.

6. The gas diffusion device according to claim 1, further comprising a fixing plate, wherein a mounting flange is arranged at the end of the diffusion cylinder, a mounting groove for accommodating the mounting flange is formed in the fixing plate, a sealing ring is arranged on the outer wall of the diffusion cylinder, the sealing ring is located on one side, away from the mounting groove, of the mounting flange, the sealing ring is fixedly connected with the fixing plate, and the fixing plate is used for being connected with the outer wall of the reaction cavity.

7. The gas diffusion device according to claim 6, wherein one end of the diffusion cylinder provided with the mounting flange is provided with an opening, and a bottom of the mounting groove is provided with a heat dissipation hole penetrating through the fixing plate, and the heat dissipation hole corresponds to the opening position of the diffusion cylinder.

8. The gas diffusion device according to claim 6, wherein a plurality of first gas inlet holes are formed in the fixing plate and surround the mounting groove, a plurality of second gas inlet holes are formed in the sealing ring and correspond to the first gas inlet holes one by one, and the gas enters the diffusion cylinder through the first gas inlet holes, the second gas inlet holes and the diffusion holes.

9. A vapor deposition apparatus comprising a chamber and a gas diffusion device according to any one of claims 1 to 8 rotatably disposed in an inlet passage of the chamber.