CVD deposition apparatus

Abstract

The application belongs to the technical field of chemical vapor deposition, and discloses a CVD deposition device, which comprises an acceleration pipeline, wherein the acceleration 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; the inlet end of the insulating pipe body is provided with a metal cathode; reactants enter the insulating pipe body through the metal cathode; the metal cathode extends towards the outlet end of the insulating pipe body; the outlet end of the insulating pipe body is provided with a metal anode; the negative electrode end of the power supply is connected with the metal cathode; the positive electrode end of the power supply is connected with the metal anode; and the power supply selectively makes the metal cathode and the metal anode be electrified or be disconnected. The CVD deposition device firstly ionizes the reactants when the reactants pass through the acceleration pipeline before the reactants enter a reaction chamber and are ionized into a plasma state by an electrode module, and then the reactants enter the reaction chamber to be ionized for the second time, so that the CVD film deposition rate is improved, the deposition time is reduced, and the production efficiency is ensured.

Description

Technical Field

[0001] This invention relates to the field of chemical vapor deposition technology, and more particularly to a CVD deposition apparatus. Background Technology

[0002] Chemical vapor deposition (CVD) is a method that uses chemical gases to react on the surface of a substrate under certain temperature and pressure to synthesize coatings or nanomaterials. It is widely used in semiconductors, hard alloys and other fields.

[0003] Currently, such as Figure 1 As shown, during CVD deposition, the reactants enter the reaction chamber 2' in gaseous form through the inlet pipe 1'. The inlet pipe 1' is equipped with a preheating module 3' to heat the reactants passing through it. After passing through the electrode module 4' at the top of the reaction chamber 2', the reactants are essentially ionized into a plasma state and then diffused to the substrate surface via the diffuser 5' to form a thin film. Since the film deposition rate and thickness of the CVD deposition apparatus are directly proportional to the plasma ionization degree and strongly correlated with the plasma diffusion rate, insufficient plasma ionization or low plasma velocity will lead to a low CVD film deposition rate and a longer deposition time, affecting production efficiency.

[0004] Therefore, there is an urgent need to design a new CVD deposition device to improve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a CVD deposition apparatus to solve the technical problem that insufficient plasma ionization or low operating speed leads to low CVD film deposition rate and long deposition time, which affects production efficiency.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] A CVD deposition apparatus includes a reaction chamber and an inlet pipe connected to the reaction chamber, and an acceleration pipe. The acceleration pipe includes an insulating tube and a power supply. The inlet end of the insulating tube is connected to the outlet end of the inlet pipe. A metal cathode is disposed at the inlet end of the insulating tube. Reactants enter the insulating tube through the metal cathode. The metal cathode extends toward the outlet end of the insulating tube. A metal anode is disposed at the outlet end of the insulating tube. 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 energizes / de-energizes the metal cathode and the metal anode.

[0008] As a preferred scheme of the CVD deposition device, the metal cathode comprises 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 pipe body, the guide electrode is coaxially arranged with the insulating pipe body, the guide electrode is located in the insulating pipe 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 scheme of the CVD deposition device, the one end of the guide electrode away from the diffusion electrode is a cone structure, and the tip of the cone structure is directed to the metal anode.

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

[0011] As a preferred scheme of the CVD deposition device, the insulating pipe body at least comprises an ionization section and a flow guide section, the metal cathode is arranged at one end of the ionization section, the other end of the ionization section is connected with the flow guide section, and the diameter of the flow guide section gradually decreases from the one end connected with the ionization section to the other end.

[0012] As a preferred scheme of the CVD deposition device, the insulating pipe body further comprises a mounting section, one end of the mounting section is arranged at the small opening end of the flow guide section, the other end of the mounting section is connected with the metal anode, and the mounting section is externally sleeved with a magnetic ring.

[0013] As a preferred scheme of the CVD deposition device, the metal anode is a horn shape, and the diameter of the metal anode gradually increases from the one end connected with the outlet end of the insulating pipe body to the other end.

[0014] As a preferred scheme of the CVD deposition device, the inlet end of the insulating pipe body and the outlet end of the gas inlet pipe, and the outlet end of the insulating pipe body and the metal anode are connected through a flange structure.

[0015] As a preferred scheme of the CVD deposition device, a sealing element is arranged at the connection of the flange structure.

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

[0017] The beneficial effects of the present application are as follows:

[0018] Case 1): when the plasma ionization degree needs to be improved, the power supply is in a power-on state with the metal cathode and the metal anode, the reactant enters the metal cathode through the gas inlet pipeline, the electrode starts to generate electrons in the power-on state, and the gaseous reactant will be ionized into a plasma state. With the increase of the temperature of the reactant, the plasma expands in the insulating pipe body, and the current generated by the electrons will provide the plasma with the Lorentz force, and through the Lorentz force, the plasma and the electrons are accelerated to the metal anode, and then enter the reaction chamber.

[0019] In summary, during the CVD deposition, before the reactant is ionized into a plasma state by the electrode module when the reactant enters the reaction chamber, the reactant is first ionized when passing through the acceleration pipeline, and then enters the reaction chamber for the second ionization, which increases the plasma degree of the ionization step and also accelerates the running speed of the plasma, improves the CVD film deposition rate, reduces the deposition time, guarantees the production efficiency, and prolongs the service life of the device.

[0020] Case 2): when the plasma ionization degree does not need to be improved, the power supply is in a power-off state with the metal cathode and the metal anode, and at this time, the acceleration pipeline is only used as a gas inlet pipeline. BRIEF DESCRIPTION OF DRAWINGS

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

[0022] Figure 2 It is a structural schematic diagram of the CVD deposition device provided by the embodiment of the application.

[0023] Figure 3 It is a structural schematic diagram of the acceleration pipeline provided by the embodiment of the application.

[0024] Figure 1 In the figure:

[0025] 1', gas inlet pipeline; 2', reaction chamber; 3', preheating module; 4', electrode module; 5', diffuser.

[0026] Figures 2-3 In the figure:

[0027] 1, gas inlet pipeline; 2, reaction chamber; 3, acceleration pipeline;

[0028] 31, insulating pipe body; 311, ionization section; 312, flow guide section; 313, mounting section;

[0029] 32, power supply;

[0030] 33, metal cathode; 331, diffusion electrode; 332, guide electrode;

[0031] 34, metal anode;

[0032] 35. A magnetic ring;

[0033] 36. A flange structure;

[0034] 37. A gasket. DETAILED DESCRIPTION

[0035] The application will be further described below in conjunction with the drawings and embodiments. It is to be understood that the specific embodiments described herein are merely illustrative of the application and are not intended to limit the application. It is also to be understood that, for the purpose of description, only the parts and structures that are related to the application are shown in the drawings.

[0036] In the description of the application, unless otherwise clearly specified and limited, the terms "connected", "connected", "fixed" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.

[0037] In the present application, unless otherwise clearly specified and limited, the "upper" or "lower" of the first feature to the second feature can include that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the "upper", "above" and "on" of the first feature to the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The "below", "below" and "below" of the first feature to the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0038] In the description of the present embodiment, the terms "upper", "lower", "right", etc. orientation or position relationship is based on the orientation or position relationship shown in the drawings, only for the convenience of description and simplification of operation, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore cannot be understood as a limitation on the application. In addition, the terms "first", "second" are only used to distinguish in the description, and have no special meaning.

[0039] Combination Figure 2 And Figure 3 As shown in the figure, the present embodiment provides a CVD deposition device, which comprises a reaction chamber 2 and a gas inlet pipe 1 connected with the reaction chamber 2, and the reactants enter the reaction chamber 2 from the gas inlet pipe 1.

[0040] Further, the CVD deposition device of the embodiment further comprises an acceleration pipeline 3, the acceleration pipeline 3 comprises an insulating pipeline body 31 and a power supply 32, the insulating pipeline body 31 is arranged between the gas inlet pipeline 1 and the reaction chamber 2, that is, the inlet end of the insulating pipeline body 31 is connected with the outlet end of the gas inlet pipeline 1, the outlet end of the insulating pipeline body 31 extends into the reaction chamber 2, and the insulating pipeline body 31 is sealingly connected with the reaction chamber 2, that is, part of the insulating pipeline body 31 extends into the reaction chamber 2, or other embodiments can also be that the insulating pipeline body 31 entirely extends into the reaction chamber 2. The embodiment adds the acceleration pipeline 3 between the gas inlet pipeline 1 and the reaction chamber 2.

[0041] In other embodiments, the outlet end of the insulating pipeline body 31 is sealingly connected with the reaction chamber 2, that is, the insulating pipeline body 31 is located outside the reaction chamber, only the outlet end is connected with the reaction chamber 2, and the arrangement position of the insulating pipeline body 31 can be arranged according to actual conditions, which is not limited herein.

[0042] Specifically, referring to Figure 3 , the inlet end of the insulating pipeline body 31 is provided with a metal cathode 33, the reactant enters the insulating pipeline body 31 through the metal cathode 33, the metal cathode 33 extends towards the outlet end of the insulating pipeline body 31, and the outlet end of the insulating pipeline body 31 is provided with a metal anode 34. The negative end of the power supply 32 is connected with the metal cathode 33, the positive end of the power supply 32 is connected with the metal anode 34, and the power supply 32 is selectively powered on / off with the metal cathode 33 and the metal anode 34.

[0043] In addition, a sealing ring can also be arranged between the metal cathode 33 and the insulating pipeline body 31, and the sealing ring is made of rubber material; or a layer of Teflon coating is coated on the surface where the insulating pipeline body 31 is connected with the metal cathode 33, so as to ensure the insulation isolation effect of the metal cathode 33 and the insulating pipeline 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 is in a powered-on state with the metal cathode 33 and the metal anode 34, the reactant enters the metal cathode 33 through the gas inlet pipeline 1, the electrode starts to generate electrons in the powered-on state, the gaseous reactant is ionized into a plasma state, accompanied by the increase of the temperature of the reactant, the plasma expands in the insulating pipeline body 31, and the current generated by the electrons will provide the plasma with Lorentz force, and the plasma and the electrons are accelerated to the metal anode 34 through the Lorentz force, and then enter the reaction chamber 2.

[0045] Among them, the Lorentz force is the force that the moving charge receives in the magnetic field, that is, the action force of the magnetic field on the moving charge. It should be noted that the direction of the Lorentz force is always perpendicular to 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 first undergo a primary ionization when passing through the acceleration pipeline 3, and then enter the reaction chamber 2 for a second ionization, which greatly improves the plasma degree of the primary ionization step and also accelerates the running speed of the plasma, thereby improving the CVD film deposition rate, reducing the deposition time, ensuring production efficiency, and prolonging the service life of the device.

[0047] When the deposition effect of the CVD deposition device is good, and the plasma ionization degree does not need to be improved, the power supply 32 and the metal cathode 33 and the metal anode 34 are in a non-conductive state, at this time, the acceleration pipeline 3 is only used as the gas inlet pipeline 1.

[0048] Preferably, as shown in Figure 3 The metal cathode 33 includes a diffusion electrode 331 and a guide electrode 332, the diffusion electrode 331 is a mesh structure, and the mesh hole diameter of the diffusion electrode 331 is 0.5mm-1mm, and the preferred value in the embodiment is 0.5mm, and in other embodiments it can also be 0.6mm, 0.7mm, 0.8mm, 0.9mm or 1mm, etc. The guide electrode 332 is a cylindrical structure. The diffusion electrode 331 is arranged at the inlet end of the insulating pipe body 31, and the diffusion electrode 331 completely covers the inlet section of the insulating pipe body 31, ensuring that the introduced reactants must pass through the diffusion electrode 331 to enter the insulating pipe body 31. The guide electrode 332 is coaxially arranged with the insulating pipe body 31, and the guide electrode 332 is located inside the insulating pipe 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 move rapidly along the axial direction of the insulating pipe body 31 towards the metal anode 34, thereby accelerating the moving speed of the plasma.

[0049] The other end of the guide electrode 332 away from the diffusion electrode 331 is a conical structure, and the tip of the diffusion electrode 331 faces the metal anode 34, and the tip of the diffusion electrode 331 is coaxially arranged with the guide electrode 332, and the guide electrode 332 with a conical structure has better guiding performance and better guiding effect.

[0050] Preferably, as shown in Figure 3 The metal anode 34 is a horn shape, and the diameter of the metal anode 34 gradually increases from one end connected to the outlet end of the insulating pipe body 31 to the other end. The diameter of the insulating pipe body 31 as a whole is larger at both ends than at the middle section. According to the effect of the narrow tube, when the plasma and electrons are accelerated to the metal anode 34, the shape of the metal anode 34 makes the electrons have a tendency to move outward, which will move together with the plasma, so that the plasma can be quickly introduced into the reaction chamber 2 from the metal anode 34.

[0051] Preferably, asFigure 3 As shown, the insulating tube 31 is made of ceramic material, which ensures that the insulating tube 31 can be insulated from the metal cathode 33 and the metal anode 34. The insulating tube 31 comprises an ionization section 311, a flow 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 flow guide section 312. The diameter of the flow guide section 312 gradually decreases from the end connected to the ionization section 311 to the other end, that is, the diameter of the middle part of the acceleration tube 3 is smaller than that of the two ends, thereby helping to accelerate the airflow. One end of the mounting section 313 is arranged at the small end of the flow guide section 312, and the other end of the mounting section 313 is connected to the metal anode 34. The mounting section 313 is sleeved with a magnetic ring 35. The magnetic ring 35 arranged at the middle part of the insulating tube 31 generates a specified strength of Lorentz force. The magnetic field generated by the magnetic ring 35 forces the plasma to rotate in a circular motion. When the rotating plasma reaches the outlet, the magnetic field generated by the magnetic field lines of the outermost magnetic ring 35 is perpendicular, and the Lorentz force acts on the right side, so that the plasma is accelerated and pushed out.

[0052] Specifically, the inlet end of the insulating tube 31 is connected to the outlet end of the air inlet pipe 1, and the outlet end of the insulating tube 31 is connected to the metal anode 34 through a flange structure 36. Since the specific structure of the flange structure 36 is prior art, it will not be described further here. The connection part of the flange structure 36 is provided with a sealing element, which is a gasket 37 located between two flanges to ensure the sealing property of the acceleration tube 3.

[0053] Obviously, the above embodiments of the present application are only examples for clearly illustrating the present application, and are not intended to limit the implementation modes of the present application. For those skilled in the art, various obvious changes, re-adjustments and replacements can be made without departing from the protection scope of the present application. It is unnecessary and impossible to enumerate all the implementation modes. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the claims of the present application.

Claims

1. A CVD deposition apparatus, comprising a reaction chamber and an inlet pipe connected to the reaction chamber, characterized in that, It also includes an acceleration conduit, which comprises an insulating tube and a power source. The inlet end of the insulating tube is connected to the outlet end of the air intake conduit. A metal cathode is provided at the inlet end of the insulating tube. Reactants enter the insulating tube through the metal cathode. The metal cathode extends toward the outlet end of the insulating tube. A metal anode is provided at the outlet end of the insulating tube. The negative terminal of the power source is connected to the metal cathode, and the positive terminal of the power source is connected to the metal anode. The power source selectively energizes / de-energizes the metal cathode and the metal anode. The metal cathode includes a diffusion electrode and a guide electrode. The diffusion electrode has a mesh structure and is disposed at the inlet end of the insulating tube. The guide electrode is coaxially disposed with the insulating tube and is located inside the insulating tube. One end of the guide electrode is disposed at the center of the end face of the diffusion electrode. The insulating tube body includes at least an ionization section and a current-conducting section. The metal cathode is disposed at one end of the ionization section, and the other end of the ionization section is connected to the current-conducting section. The diameter of the current-conducting section gradually decreases from the end connected to the ionization section toward the other end. The insulating tube also includes an installation section, one end of which is located at the small opening of the flow guiding section, and the other end of which is connected to the metal anode. A magnetic ring is fitted around the outside of the installation section.

2. The CVD deposition apparatus according to claim 1, characterized in that, 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.

3. The CVD deposition apparatus according to claim 1, characterized in that, The pore size of the diffusion electrode is 0.5mm-1mm.

4. The CVD deposition apparatus according to any one of claims 1-3, characterized in that, The metal anode is trumpet-shaped, and its diameter gradually increases from one end connected to the outlet end of the insulating tube toward the other end.

5. The CVD deposition apparatus according to any one of claims 1-3, characterized in that, The inlet end of the insulating tube is connected to the outlet end of the air inlet pipe, and the outlet end of the insulating tube is connected to the metal anode via flange structures.

6. The CVD deposition apparatus according to claim 5, characterized in that, The flange structure is equipped with a sealing element at the connection.

7. The CVD deposition apparatus according to any one of claims 1-3, characterized in that, The insulating tube is made of ceramic material.

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