CVD deposition device

Abstract

The invention belongs to the technical field of chemical vapor deposition, and discloses a CVD (chemical vapor deposition) device which comprises an accelerating pipeline, the accelerating pipeline comprises an insulating pipe body and a power supply, the inlet end of the insulating pipe body is connected with the outlet end of a gas inlet pipeline, a metal cathode is arranged at the inlet end of the insulating pipe body, a reactant enters the insulating pipe body through the metal cathode, and the reactant enters the gas inlet pipeline through the power supply. The metal cathode extends towards the outlet end of the insulating tube body, the outlet end of the insulating tube body is provided with a metal anode, the cathode end of the power supply is connected with the metal cathode, the anode end of the power supply is connected with the metal anode, and the power supply selectively enables the metal cathode and the metal anode to be powered on / off. According to the CVD deposition device, before reactants enter the reaction chamber and are ionized into a plasma state by the electrode module, the reactants are ionized for the first time when passing through the acceleration pipeline, and then enter the reaction chamber to be ionized for the second time, so that the deposition rate of a CVD film is increased, the deposition time is shortened, and the production efficiency is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of chemical vapor deposition, and in particular to a CVD deposition device. Background Art

[0002] Chemical Vapor Deposition (CVD) is a method in which chemical gases react on the surface of a substrate under a certain temperature and pressure to synthesize coatings or nanomaterials. It is widely used in semiconductors, cemented carbide and other fields.

[0003] Currently, if Figure 1 As shown, when CVD deposition is carried out, the reactants enter the reaction chamber 2' in the form of gas through the air inlet pipe 1'. The air inlet pipe 1' is provided with a preheating module 3' for heating the reactants passing through the air inlet pipe 1'. After the reactants pass through the electrode module 4' on the upper part of the reaction chamber 2' and are basically ionized into a plasma state, they are diffused to the surface of the substrate through the diffuser 5' to form a thin film. Since the film forming rate and film thickness of the CVD deposition device are proportional to the plasma ionization degree and have a strong correlation with the diffusion speed of the plasma, when the plasma ionization degree is insufficient or the movement speed is low, the CVD film deposition rate will be low, and the deposition time will be long, affecting the production efficiency.

[0004] Therefore, it is urgent to design a new CVD deposition device to improve the above problems. Summary of the invention

[0005] The object of the present invention is to provide a CVD deposition device to solve the technical problem that when the plasma ionization degree is insufficient or the operating speed is low, the CVD film deposition rate will be low and the deposition time will be long, affecting the production efficiency.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] A CVD deposition device comprises a reaction chamber and an air intake pipe connected to the reaction chamber, and also comprises an acceleration pipe, wherein the acceleration pipe comprises an insulating tube body and a power supply, wherein the inlet end of the insulating tube body is connected to the outlet end of the air intake pipe, a metal cathode is arranged at the inlet end of the insulating tube body, reactants enter the insulating tube body through the metal cathode, the metal cathode extends toward the outlet end of the insulating tube body, a metal anode is arranged at the outlet end of the insulating tube body, a negative terminal of the power supply is connected to the metal cathode, a positive terminal of the power supply is connected to the metal anode, and the power supply selectively energizes / de-energizes the metal cathode and the metal anode.

[0008] As a preferred solution of the CVD deposition device, the metal cathode includes a diffusion electrode and a guide electrode, the diffusion electrode is a mesh structure, the diffusion electrode is arranged at the inlet end of the insulating tube body, the guide electrode is coaxially arranged with the insulating tube body, the guide electrode is located inside the insulating tube body, and one end of the guide electrode is arranged at the center of the end surface of the diffusion electrode.

[0009] As a preferred solution of the CVD deposition device, the end of the guide electrode away from the diffusion electrode is a cone structure, and the tip of the cone structure faces the metal anode.

[0010] As a preferred solution of the CVD deposition device, the mesh size of the diffusion electrode is 0.5 mm-1 mm.

[0011] As a preferred solution of the CVD deposition device, the insulating tube body includes at least an ionization section and a guide section, the metal cathode is arranged at one end of the ionization section, the other end of the ionization section is connected to the guide section, and the diameter of the guide section gradually decreases from one end connected to the ionization section toward the other end.

[0012] As a preferred solution of the CVD deposition device, the insulating tube body also includes a mounting section, one end of which is arranged at the small end of the guide section, the other end of which is connected to the metal anode, and the outer sleeve of the mounting section is provided with a magnetic ring.

[0013] As a preferred solution of the CVD deposition device, the metal anode is trumpet-shaped, and the diameter of the metal anode gradually increases from one end connected to the outlet end of the insulating tube body toward the other end thereof.

[0014] As a preferred solution of the CVD deposition device, the inlet end of the insulating tube body and the outlet end of the air inlet pipe, as well as the outlet end of the insulating tube body and the metal anode are connected via a flange structure.

[0015] As a preferred solution of the CVD deposition device, a sealing member is provided at the connection of the flange structure.

[0016] As a preferred solution of the CVD deposition device, the insulating tube body is made of ceramic material.

[0017] Beneficial effects of the present invention:

[0018] Case 1): When the plasma ionization degree needs to be increased, the power supply, the metal cathode and the metal anode are in a powered state, and the reactants enter the metal cathode through the air inlet pipe. In the powered state, the electrode begins to generate electrons, and the gaseous reactants will be ionized into a plasma state. As the temperature of the reactants increases, the plasma expands in the insulating tube body, and the current generated by the electrons will provide Lorentz force for the plasma. Through the Lorentz force, the plasma and the electrons are accelerated to the metal anode and then enter the reaction chamber.

[0019] In summary, when CVD deposition is carried out, before the reactants enter the reaction chamber and are ionized into a plasma state by the electrode module, the reactants are first ionized when passing through the acceleration pipe, and then enter the reaction chamber for a second ionization. The plasma degree is greatly improved by adding one ionization step, and the operation speed of the plasma is also accelerated, thereby increasing the CVD film deposition rate, reducing the deposition time to ensure production efficiency, and extending the service life of the device.

[0020] Case 2): When there is no need to increase the plasma ionization degree, the power supply and the metal cathode and the metal anode are in an unpowered state, and the acceleration duct is only used as an air intake duct. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of a CVD deposition device provided by the background technology of the present invention.

[0022] Figure 2 It is a schematic diagram of the structure of a CVD deposition device provided in an embodiment of the present invention.

[0023] Figure 3 It is a schematic diagram of the structure of an acceleration pipeline provided by an embodiment of the present invention.

[0024] Figure 1 middle:

[0025] 1', air intake pipe; 2', reaction chamber; 3', preheating module; 4', electrode module; 5', diffuser.

[0026] Figure 2-Figure 3 middle:

[0027] 1. Air intake pipe; 2. Reaction chamber; 3. Acceleration pipe;

[0028] 31. Insulating tube body; 311. Ionization section; 312. Guide section; 313. Installation section;

[0029] 32. Power supply;

[0030] 33. Metal cathode; 331. Diffusion electrode; 332. Guide electrode;

[0031] 34. Metal anode;

[0032] 35. Magnetic ring;

[0033] 36. Flange structure;

[0034] 37. Gasket. DETAILED DESCRIPTION

[0035] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0036] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0038] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0039] Combination Figure 2 and Figure 3 As shown, this embodiment provides a CVD deposition device, which includes a reaction chamber 2 and an air intake pipe 1. The air intake pipe 1 is connected to the reaction chamber 2, and reactants enter the reaction chamber 2 through the air intake pipe 1.

[0040] Furthermore, the CVD deposition device of the present embodiment further comprises an accelerating pipe 3, the accelerating pipe 3 comprises an insulating tube body 31 and a power source 32, the insulating pipe is arranged between the air intake pipe 1 and the reaction chamber 2, that is, the inlet end of the insulating tube body 31 is connected to the outlet end of the air intake pipe 1, the outlet end of the insulating tube body 31 extends into the reaction chamber 2, and the insulating tube body 31 is sealedly connected to the reaction chamber 2, that is, part of the insulating tube body 31 extends into the reaction chamber 2, or, in other embodiments, the insulating tube body 31 may extend completely into the reaction chamber 2. In the present embodiment, an accelerating pipe 3 is additionally arranged between the air intake pipe 1 and the reaction chamber 2.

[0041] In other embodiments, the outlet end of the insulating tube body 31 is sealed and connected to the reaction chamber 2, that is, the insulating tube body 31 is located outside the reaction chamber, and only the outlet end is connected to the reaction chamber 2. The setting position of the insulating tube body 31 can be set according to actual conditions and is not limited here.

[0042] Specifically, see Figure 3 The inlet end of the insulating tube 31 is provided with a metal cathode 33, and the reactants enter the insulating tube 31 through the metal cathode 33. The metal cathode 33 extends toward the outlet end of the insulating tube 31, and the outlet end of the insulating tube 31 is provided with a metal anode 34. The negative terminal of the power supply 32 is connected to the metal cathode 33, and the positive terminal of the power supply 32 is connected to the metal anode 34. The power supply 32 selectively powers on / off the metal cathode 33 and the metal anode 34.

[0043] In addition, a sealing ring can be arranged between the metal cathode 33 and the insulating tube body 31, and the sealing ring is made of rubber material; alternatively, a layer of Teflon coating is applied on the surface where the insulating tube body 31 and the metal cathode 33 are connected, so as to ensure the insulation isolation effect between the metal cathode 33 and the insulating tube body 31.

[0044] Case 1: When the deposition effect of the CVD deposition device is not good and the plasma ionization degree needs to be improved. The power supply 32, the metal cathode 33 and the metal anode 34 are in a powered state, and the reactants enter the metal cathode 33 through the air inlet pipe 1. In the powered state, the electrode begins to generate electrons, and the gaseous reactants will be ionized into a plasma state. With the increase in the temperature of the reactants, the plasma expands in the insulating tube body 31, and the current generated by the electrons will provide Lorentz force for the plasma. Through the Lorentz force, the plasma and the electrons are accelerated to the metal anode 34, and then enter the reaction chamber 2.

[0045] The Lorentz force is the force exerted on a moving charge in a magnetic field, that is, the force exerted by the magnetic field on the moving charge. It should be noted that the direction of the Lorentz force is always perpendicular to both the velocity direction and the magnetic induction intensity direction.

[0046] It can be understood that before the reactants enter the reaction chamber 2 and are ionized into a plasma state by the electrode module, the reactants are first ionized when passing through the acceleration pipe 3, and then enter the reaction chamber 2 for a second ionization. The plasma degree is greatly improved by adding an ionization step, and the operation speed of the plasma is also accelerated, the CVD film deposition rate is improved, the deposition time is reduced to ensure production efficiency, and the service life of the device is extended.

[0047] When the deposition effect of the CVD deposition device is good and there is no need to increase the plasma ionization degree, the power supply 32 , the metal cathode 33 and the metal anode 34 are in an unpowered state, and the acceleration pipeline 3 is only used as the air intake pipeline 1 .

[0048] Preferably, if Figure 3 As shown, the metal cathode 33 includes a diffusion electrode 331 and a guide electrode 332. The diffusion electrode 331 is a mesh structure. The aperture of the mesh of the diffusion electrode 331 is 0.5mm-1mm. In this embodiment, it is preferably 0.5mm. In other embodiments, it can also be 0.6mm, 0.7mm, 0.8mm, 0.9mm or 1mm. The guide electrode 332 is a cylindrical structure. The diffusion electrode 331 is arranged at the inlet end of the insulating tube body 31. The diffusion electrode 331 completely shields the inlet section of the insulating tube body 31 to ensure that the introduced reactants must pass through the diffusion electrode 331 before entering the insulating tube body 31. The guide electrode 332 is coaxially arranged with the insulating tube body 31. The guide electrode 332 is located inside the insulating tube body 31. One end of the guide electrode 332 is arranged at the center of the end face of the diffusion electrode 331. The guide electrode 332 guides the plasma generated after ionization to concentrate around it, and quickly moves toward the metal anode 34 along the axial direction of the insulating tube body 31, thereby accelerating the movement speed of the plasma.

[0049] Among them, the other end of the guide electrode 332 away from the diffusion electrode 331 is a cone structure, and the tip of the diffusion electrode 331 is facing the metal anode 34, and the tip of the diffusion electrode 331 is coaxially arranged with the guide electrode 332. The guide electrode 332 with a cone structure is more directional and has a better guiding effect.

[0050] Preferably, if Figure 3 As shown, the metal anode 34 is trumpet-shaped, and the diameter of the metal anode 34 gradually increases from one end connected to the outlet end of the insulating tube body 31 toward the other end thereof. The diameters of the two ends of the insulating tube body 31 as a whole are larger than the diameter of the middle section. According to the narrow tube effect, when the plasma and the electrons are accelerated to the metal anode 34 together, the shape of the metal anode 34 makes the electrons tend to move outward, and will move together with the plasma, so that the plasma can be quickly introduced from the metal anode 34 into the reaction chamber 2.

[0051] Preferably, if Figure 3 As shown, the insulating tube body 31 is made of ceramic material to ensure that the insulating tube body 31 can be insulated and isolated from the metal cathode 33 and the metal anode 34. The insulating tube body 31 includes an ionization section 311, a guide section 312 and a mounting section 313. The metal cathode 33 is arranged at one end of the ionization section 311, and the other end of the ionization section 311 is connected to the guide section 312. The diameter of the guide section 312 gradually decreases from the end connected to the ionization section 311 toward the other end thereof, that is, the diameter of the middle of the acceleration pipe 3 is smaller than that at the two ends, thereby facilitating the acceleration of the airflow. One end of the mounting section 313 is arranged at the small mouth end of the guide section 312, and the other end of the mounting section 313 is connected to the metal anode 34. A magnetic ring 35 is sleeved on the circumference of the mounting section 313. The magnetic ring 35 is arranged in the middle of the insulating tube body 31 to generate a Lorentz force of a specified strength. The magnetic field generated by the magnetic ring 35 forces the plasma to rotate in a circle. When the rotating plasma reaches the exit, the magnetic field generated by the magnetic flux lines of the outermost magnetic ring 35 is vertical. The Lorentz force acts on the right side, and the plasma will be accelerated and pushed out.

[0052] Specifically, the inlet end of the insulating tube body 31 and the outlet end of the intake pipe 1, and the outlet end of the insulating tube body 31 and the metal anode 34 are connected via a flange structure 36. Since the specific structure of the flange structure 36 is prior art, it is not further described here. A seal is provided at the connection of the flange structure 36, and the seal is a gasket 37. The gasket 37 is located between the two flange plates to ensure the sealing of the acceleration pipe 3.

[0053] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A CVD deposition device, comprising a reaction chamber and an air inlet pipe connected to the reaction chamber, characterized in that: It also includes an acceleration pipeline, which includes an insulating tube body and a power supply. The inlet end of the insulating tube body is connected to the outlet end of the intake tube. The inlet end of the insulating tube body is provided with a metal cathode. The reactant enters the insulating tube body through the metal cathode. The metal cathode extends toward the outlet end of the insulating tube body. The outlet end of the insulating tube body is provided with a metal anode. The negative terminal of the power supply is connected to the metal cathode, and the positive terminal of the power supply is connected to the metal anode. The power supply selectively powers on / off the metal cathode and the metal anode.

2. The CVD deposition device according to claim 1, characterized in that: The metal cathode includes a diffusion electrode and a guide electrode. The diffusion electrode is a mesh structure. The diffusion electrode is arranged at the inlet end of the insulating tube body. The guide electrode is coaxially arranged with the insulating tube body. The guide electrode is located inside the insulating tube body. One end of the guide electrode is arranged at the center of the end surface of the diffusion electrode.

3. The CVD deposition device according to claim 2, characterized in that: One end of the guide electrode away from the diffusion electrode is a cone structure, and the tip of the cone structure faces the metal anode.

4. The CVD deposition device according to claim 2, characterized in that: The mesh size of the diffusion electrode is 0.5 mm to 1 mm.

5. The CVD deposition device according to any one of claims 1 to 4, characterized in that: The insulating tube body comprises at least an ionization section and a guide section, the metal cathode is arranged at one end of the ionization section, the other end of the ionization section is connected to the guide section, and the diameter of the guide section gradually decreases from the end connected to the ionization section toward the other end.

6. The CVD deposition device according to claim 5, characterized in that: The insulating tube body also includes a mounting section, one end of which is arranged at the small opening end of the guide section, the other end of which is connected to the metal anode, and a magnetic ring is sleeved on the outside of the mounting section.

7. The CVD deposition device according to any one of claims 1 to 4, characterized in that: The metal anode is trumpet-shaped, and the diameter of the metal anode gradually increases from one end connected to the outlet end of the insulating tube body toward the other end thereof.

8. The CVD deposition device according to any one of claims 1 to 4, characterized in that: The inlet end of the insulating tube body and the outlet end of the air intake pipe, as well as the outlet end of the insulating tube body and the metal anode are connected via a flange structure.

9. The CVD deposition apparatus according to claim 8, characterized in that: A sealing member is provided at the connection of the flange structure.

10. The CVD deposition device according to any one of claims 1 to 4, characterized in that: The insulating tube body is made of ceramic material.

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