Reaction chamber and mpcvd apparatus

Abstract

The utility model relates to the field of microwave plasma technology, more particularly to a kind of reaction cavity and MPCVD device, the reaction cavity includes antenna, the cavity of inner diameter D1, the sample table of diameter D2 and the medium ring of height H1 inner diameter D3, the first boss of thickness H2 is arranged in the cavity, the first boss is provided with the through-hole of diameter D4, the first boss separates cavity into the upper chamber of height H3 and the lower chamber of height H4, H3 / H4 belongs to [2.5, 3.0], first chamfer is arranged between the first boss and upper chamber, the lower end surface of antenna is provided with the second boss of diameter D5 and the first recess of inner diameter D6, second chamfer is arranged between the second boss and first recess, the medium ring one end is arranged in first recess, other end and first boss abut, provide a kind of reaction cavity that air tightness is better, microwave feed-in efficiency is higher, it is convenient to install, the MPCVD device includes the reaction cavity.

Description

Technical Field

[0001] This utility model relates to the field of microwave plasma technology, and more specifically, to a reaction cavity and an MPCVD device. Background Technology

[0002] Microwave plasma chemical vapor deposition (MPCVD) is an advanced method for preparing high-quality diamond films. This method requires a microwave plasma chemical vapor deposition apparatus. In MPCVD, microwaves generated by a microwave generator are introduced into the reaction chamber through a waveguide transmission system, and a mixture of methane and hydrogen gas is introduced. Under the excitation of microwaves, glow discharge is generated in the reaction chamber, which ionizes the molecules of the reaction gas and generates plasma, which is deposited on the sample to obtain a diamond film.

[0003] The reaction chamber of existing MPCVD devices is inconvenient to install, difficult to ensure airtightness, has low efficiency in microwave feeding into the chamber, poor impedance matching, insufficiently stable and concentrated electric field, and low plasma density, resulting in a small discharge area that is unsuitable for the deposition of large-area diamond films, thus limiting its application prospects. Utility Model Content

[0004] The purpose of this invention is to provide a reaction chamber to solve at least one of the technical problems in the prior art.

[0005] Another objective of this invention is to provide an MPCVD apparatus that includes the aforementioned reaction chamber.

[0006] The objective of this utility model is achieved through the following technical solution: A reaction chamber includes an antenna, a cavity with an inner diameter of D1, a sample stage with a diameter of D2, and a dielectric ring with a height of H1 and an inner diameter of D3. The cavity has a first protrusion with a thickness of H2 and a through hole with a diameter of D4. The first protrusion divides the cavity into an upper chamber with a height of H3 and a lower chamber with a height of H4, where H3 / H4 ∈ [2.5, 3.0]. A first chamfer is provided between the first protrusion and the upper chamber. The lower end face of the antenna has a second protrusion with a diameter of D5 and a first groove with an inner diameter of D6. A second chamfer is provided between the second protrusion and the first groove. One end of the dielectric ring is disposed in the first groove, and the other end abuts against the first protrusion.

[0007] Furthermore, the bottom of the lower chamber is provided with a second groove with a diameter of D7, and the sample stage is disposed in the second groove, wherein D2 < D5 < D7 < D6 = D4 < D3.

[0008] Furthermore, the distance between the second protrusion and the sample stage is H5, where H4 / H5 ∈ [0.5, 0.6], H1 / H5 ∈ [0.45, 0.55], and H2 / H5 ∈ [0.05, 0.15].

[0009] Furthermore, the height of the sample stage below the lower chamber is H6, and H6 / H5 ∈ [0.20%, 0.25%].

[0010] Furthermore, D1 / D4 ∈ [1.3, 1.5], and D1 / D2 ∈ [3.0, 3.5].

[0011] Furthermore, the height of the first chamfer is H7, the thickness of the antenna edge is H8, the distance from the antenna to the upper cavity is H9, H7 / H1 ∈ [0.3, 0.5], H1 / H9 ∈ [0.25, 0.35], and H8 / H9 ∈ [0.25, 0.35].

[0012] Furthermore, a third chamfer is provided between the sample stage and the second groove.

[0013] An MPCVD apparatus includes the reaction chamber.

[0014] This utility model has the following advantages: The reaction chamber of this invention has a first protrusion inside the chamber, which divides the chamber into an upper chamber and a lower chamber. The dielectric ring is disposed between the antenna and the first protrusion. In operation, the negative pressure of the lower chamber causes the antenna to move towards the lower chamber, thereby tightly locking the dielectric ring between the antenna and the first protrusion, ensuring sealing performance. In addition, a first chamfer is provided between the first protrusion and the upper chamber, and a second protrusion is provided on the lower end face of the antenna. The first chamfer and the second protrusion can not only improve the microwave transmission efficiency, but also have a positioning function, enabling the dielectric ring to automatically and quickly become coaxial with the upper chamber. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0016] Figure 1 This is a cross-sectional schematic diagram of the reaction chamber of this utility model; Figure 2 This is a cross-sectional view of the antenna of the reaction cavity of this utility model; Figure 3This is a cross-sectional schematic diagram of the reaction chamber of this utility model; Figure 4 This is a cross-sectional schematic diagram of the medium ring in the reaction chamber of this utility model; Figure 5 This is a simulation diagram of the electric field of the reaction chamber of this utility model; In the figure: 1-antenna, 2-antenna, 3-sample stage, 4-dielectric ring, 5-first boss, 6-through hole, 7-upper chamber, 8-lower chamber, 9-second boss, 10-first groove, 11-second groove. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0018] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this utility model is in use. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0019] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0020] In this invention, unless otherwise expressly specified and limited, "above or below" the first feature may include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on" the first feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the first feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0021] like Figures 1 to 4As shown, a reaction chamber includes an antenna 1, a cavity 2 with an inner diameter of D1, a sample stage 3 with a diameter of D2, and a dielectric ring 4 with a height of H1 and an inner diameter of D3. A first protrusion 5 with a thickness of H2 is provided inside the cavity 2. The first protrusion 5 has a through hole 6 with a diameter of D4. The first protrusion 5 divides the cavity 2 into an upper chamber 7 with a height of H3 and a lower chamber 8 with a height of H4. The inner diameters of the upper chamber 7 and the lower chamber 8 are equal, and H3 / H4 ∈ [2.5, 3.0]. A first chamfer is provided between the first protrusion 5 and the upper chamber 7. The lower end face of the antenna 1 has a second protrusion 9 with a diameter of D5 and an inner diameter of D3. The first groove 10 is D6, and the second protrusion 9 has a second chamfer between it and the first groove 10. One end of the dielectric ring 4 is disposed in the first groove 10, and the other end abuts against the first protrusion 5. The antenna 1, sample stage 3, dielectric ring 4, through hole 6, lower chamber 8, and second protrusion 9 are all coaxial with the upper chamber 7. The dielectric ring 4 is made of a low dielectric constant material (e.g., quartz and ceramic). In operation, the negative pressure in the lower chamber is much greater than that in the upper chamber. In existing reaction chambers, the dielectric ring is disposed between the upper chamber and the antenna, and the negative pressure in the lower chamber often causes the seal between the dielectric ring and the upper chamber or antenna to fail. The reaction chamber of this invention, in the cavity... A first protrusion 5 is provided inside the body 2, dividing the cavity 2 into an upper chamber 7 and a lower chamber 8. A dielectric ring 4 is disposed between the antenna 1 and the first protrusion 5. In operation, the negative pressure in the lower chamber forces the antenna 1 to move towards the lower chamber, thereby tightly locking the dielectric ring 4 between the antenna 1 and the first protrusion 5, ensuring sealing performance. In addition, the height ratio H3 / H4 between the upper chamber 7 and the lower chamber 8 ∈ [2.5, 3.0] can improve microwave utilization. The second protrusion 9 can confine the plasma and make the plasma sphere flatter, thus facilitating the deposition of a large-area diamond film. The first chamfer and the second chamfer can improve microwave efficiency. In addition to improving transmission efficiency, it also has a positioning function, enabling the dielectric ring 4 to automatically and quickly align with the upper chamber 7. Specifically, both the first and second chamfers are coaxial with the upper chamber 7. The upper end of the dielectric ring 4 is fitted onto the second cone formed by the second chamfer, and the lower end of the dielectric ring 4 is fitted into the first cone formed by the first chamfer. When the antenna 1 moves toward the lower chamber 8, the upper end of the dielectric ring 4 falls into the first groove 10 coaxial with the upper chamber 7 under the action of the second cone, and the lower end of the dielectric ring 4 slides into the first cone coaxial with the upper chamber 7 under the action of the first cone, thus realizing the automatic and rapid alignment of the entire dielectric ring 4 with the upper chamber 7, which facilitates installation.

[0022] Furthermore, in order to better confine the plasma, the bottom of the lower chamber 8 is provided with a second groove 11 with a diameter of D7, and the sample stage 3 is disposed in the second groove 11. The second groove 11 and the sample stage 3 are both coaxial with the upper chamber 7, and D2 < D5 < D7 < D6 = D4 < D3.

[0023] Furthermore, in order to ensure stable discharge and avoid abnormal conditions such as ball bouncing and flickering, the distance between the second protrusion 9 and the sample stage 3 is H5, where H4 / H5 ∈ [0.5, 0.6], H1 / H5 ∈ [0.45, 0.55], and H2 / H5 ∈ [0.05, 0.15].

[0024] Furthermore, in order to increase the discharge area and thus be suitable for depositing a large-area diamond film, the height of the sample stage 3 below the bottom surface of the lower chamber 8 is H6, and the H6 / H5 ∈ [0.20%, 0.25%].

[0025] Furthermore, in order to achieve stable discharge and avoid abnormal conditions such as ball bouncing and flickering, D1 / D4 ∈ [1.3, 1.5], and D1 / D2 ∈ [3.0, 3.5].

[0026] Furthermore, in order to improve the transmission efficiency of microwaves, the height of the first chamfer is H7, the edge thickness of the antenna 1 is H8, the distance from the antenna 1 to the top surface of the upper cavity 7 is H9, H7 / H1 ∈ [0.3, 0.5], H1 / H9 ∈ [0.25, 0.35], and H8 / H9 ∈ [0.25, 0.35].

[0027] Furthermore, in order to improve the uniformity of the electric field distribution, a third chamfer is provided between the sample stage 3 and the bottom surface of the second groove 11, and the height of the third chamfer is lower than the upper surface of the sample stage 3.

[0028] An MPCVD apparatus includes the reaction chamber.

[0029] like Figure 5 As shown in the simulation, the reaction chamber of this invention is easy to install, has good airtightness, high microwave feeding efficiency, stable and concentrated electric field, and large discharge area, making it suitable for depositing large-area diamond films.

[0030] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A reaction chamber, comprising an antenna (1), a cavity (2) with an inner diameter of D1, a sample stage (3) with a diameter of D2, and a dielectric ring (4) with a height of H1 and an inner diameter of D3, characterized in that: The cavity (2) is provided with a first boss (5) with a thickness of H2. The first boss (5) is provided with a through hole (6) with a diameter of D4. The first boss (5) divides the cavity (2) into an upper chamber (7) with a height of H3 and a lower chamber (8) with a height of H4. H3 / H4∈[2.5,3.0]. A first chamfer is provided between the first boss (5) and the upper chamber (7). The lower end face of the antenna (1) is provided with a second boss (9) with a diameter of D5 and a first groove (10) with an inner diameter of D6. A second chamfer is provided between the second boss (9) and the first groove (10). One end of the dielectric ring (4) is located in the first groove (10) and the other end abuts against the first boss (5).

2. The reaction chamber according to claim 1, characterized in that: The bottom of the lower chamber (8) is provided with a second groove (11) with a diameter of D7, and the sample stage (3) is located in the second groove (11), wherein D2 < D5 < D7 < D6 = D4 < D3.

3. The reaction chamber according to claim 2, characterized in that: The distance between the second protrusion (9) and the sample stage (3) is H5, where H4 / H5 ∈ [0.5, 0.6], H1 / H5 ∈ [0.45, 0.55], and H2 / H5 ∈ [0.05, 0.15].

4. The reaction chamber according to claim 3, characterized in that: The height of the sample stage (3) below the lower chamber (8) is H6, and H6 / H5 ∈ [0.20%, 0.25%].

5. The reaction chamber according to claim 4, characterized in that: The D1 / D4 ∈ [1.3, 1.5], and the D1 / D2 ∈ [3.0, 3.5].

6. The reaction chamber according to claim 5, characterized in that: The height of the first chamfer is H7, the edge thickness of the antenna (1) is H8, the distance from the antenna (1) to the upper chamber (7) is H9, H7 / H1 ∈ [0.3, 0.5], H1 / H9 ∈ [0.25, 0.35], and H8 / H9 ∈ [0.25, 0.35].

7. The reaction chamber according to any one of claims 1 to 6, characterized in that: A third chamfer is provided between the sample stage (3) and the second groove (11).

8. An MPCVD apparatus, characterized in that: Includes the reaction chamber as described in any one of claims 1 to 7.

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