Vacuum pipeline structure for improving cleanliness of vacuum system of CVD (Chemical Vapor Deposition) equipment

Abstract

The invention provides a vacuum pipeline structure for improving the cleanliness of a vacuum system of CVD (Chemical Vapor Deposition) equipment, which comprises a vacuum chamber, an external vacuum pipe assembly and an embedded vacuum pipe assembly, and the two ends of the embedded vacuum pipe assembly are respectively communicated with the external vacuum pipe assembly; the embedded vacuum tube assemblies are divided into two sets, the two sets of embedded vacuum tube assemblies are located at the upper end and the lower end of the vacuum chamber respectively, each set of embedded vacuum tube assembly comprises a plurality of embedded vacuum tubes, the embedded vacuum tubes are evenly arranged in the vacuum chamber, each embedded vacuum tube is provided with a hole, and the external vacuum tube assembly is connected with a main vacuum tube. The end, away from the external vacuum tube assembly, of the main vacuum tube is connected with a dry pump. Dust is absorbed from the four corners and the periphery of the vacuum chamber in all directions through the holes in the embedded vacuum tubes, and the dust is prevented from falling on the substrate. And in the vacuumizing process, the fully-distributed holes can also avoid the water vapor condensation phenomenon generated in the local area near the vacuum pipe in the prior art.

Description

Technical Field

[0001] This invention relates to the field of chemical vapor deposition equipment technology, and in particular to a vacuum pipeline structure for improving the cleanliness of the vacuum system in CVD equipment. Background Technology

[0002] Figure 1 This is a vacuum chamber component of a chemical vapor deposition (CVD) system. First, the atmospheric robotic arm 40 moves the substrate 41 into the loading chamber 42. The vacuum valve 43 opens, allowing atmosphere to pass through the vacuum tube 44. A dry pump 45 then extracts the atmosphere from the loading chamber 42, achieving the required vacuum level. Once the loading chamber 42 reaches the required vacuum level, the vacuum robotic arm 47 in the vacuum transfer chamber 46 moves the substrate to the process chamber 48 for processing. Maintaining the vacuum level and controlling the pressure in the vacuum transfer chamber 46 and process chamber 48 are similar to those in the loading chamber 42.

[0003] Figure 2 Schematic diagram of the structure for connecting the existing vacuum tube 44 to the loading cavity 42 and the vacuum transfer cavity 46 Figure 1 The chamber has only one connection point to the vacuum tube 44. Taking the loading chamber as an example, since the loading chamber is responsible for switching between atmosphere and vacuum, it faces two major challenges: Problem 1: During the vacuuming process, the external metal structure of the chamber is compressed by atmospheric pressure, resulting in microscopic deformation. This causes metal fatigue and friction to gradually occur at metal welds, stress points, and between metal structures, generating dust that contaminates the substrate.

[0004] Challenge 2: The vacuuming speed affects the production cycle and output. However, the vacuuming speed should not be too fast to avoid the "adiabatic expansion cooling effect," which can lead to the formation of water vapor (aerosol, white mist) in the chamber, resulting in abnormal product yield.

[0005] In the past decade, to alleviate the above problems, the loading chamber has been designed with openings on the left, right, or top and bottom sides to symmetrically connect vacuum tubes, such as... Figure 3 Show, Figure 3 Schematic diagram of the structure for connecting existing vacuum tubes to the loading chamber or vacuum transfer chamber. Figure 2 This structure has limited effectiveness in improving the cleanliness of the vacuum chamber and increasing the pumping rate while preventing water vapor generation. For example... Figure 4 During the vacuuming process in the middle and rear chambers, dust 49 in the corners cannot be discharged through the vacuum tube, and Figure 4 Even if the pumping speed on the front side is too fast, an "adiabatic expansion cooling effect" will still occur near the vacuum tube, generating water vapor 50. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a vacuum pipeline structure that improves the cleanliness of the vacuum system of CVD equipment, which can prevent the vacuum chamber from being damaged due to the continuous accumulation of dust; at the same time, it can prevent the generation of water vapor, increase the pumping rate, and thus increase the production capacity.

[0007] This invention is implemented as follows: This invention provides a vacuum pipeline structure for improving the cleanliness of the vacuum system of CVD equipment, including a vacuum chamber, an external vacuum tube assembly located outside the vacuum chamber, and an embedded vacuum tube assembly located inside the vacuum chamber, wherein both ends of the embedded vacuum tube assembly are respectively connected to the external vacuum tube assembly. The embedded vacuum tube assembly is divided into two groups, which are located at the upper and lower ends of the vacuum chamber, respectively. Each group of embedded vacuum tube assemblies includes several embedded vacuum tubes, which are evenly arranged inside the vacuum chamber. Each embedded vacuum tube has a hole. The external vacuum tube assembly is connected to the main vacuum tube, which is also equipped with a main vacuum valve. The end of the main vacuum tube away from the external vacuum tube assembly is connected to a dry pump.

[0008] Furthermore, the main vacuum tube is also connected to a secondary vacuum tube, and a secondary vacuum valve is provided on the secondary vacuum tube.

[0009] Furthermore, the diameter of the secondary vacuum tube is smaller than the diameter of the main vacuum tube.

[0010] Furthermore, the holes on the embedded vacuum tube are distributed in a gradient, wherein the hole density is highest in the middle region of the embedded vacuum tube, and the hole density gradually decreases from the middle region toward the direction closer to the outer vacuum tube.

[0011] Furthermore, each group of external vacuum tube assemblies includes several external vacuum tubes, the number of which is twice that of the embedded vacuum tubes. The external vacuum tubes are divided into two groups, located at both ends of the embedded vacuum tubes respectively. Each group of external vacuum tubes is connected by a connecting pipe, which is connected to a branch pipe. A flexible second corrugated pipe is provided on the branch pipe.

[0012] Furthermore, one end of the embedded vacuum tube has a flange face, the flange face is located outside the vacuum chamber, and the flange face is fastened to the outer wall of the vacuum chamber by a first bolt, and a first sealing ring is provided between the flange face and the outer wall of the vacuum chamber. The outer wall of the other end of the embedded vacuum tube is provided with a first oblique opening, and the side wall of the vacuum chamber is provided with a second oblique opening corresponding to the first oblique opening. A third sealing ring is connected between the first oblique opening and the second oblique opening. The other end of the embedded vacuum tube is also connected with a fixing bolt, which passes through the tube wall of the embedded vacuum tube and is locked to the side wall of the vacuum chamber.

[0013] Furthermore, each of the external vacuum tubes is connected to a first bellows at the end facing the embedded vacuum tube. The inner diameter of the first bellows is larger than the outer diameter of the flange face. The end of the first bellows away from the external vacuum tube is connected to the outer wall of the vacuum chamber so as to enclose the flange face inside the first bellows.

[0014] Furthermore, a second sealing ring is provided at both ends of the first bellows.

[0015] Furthermore, the vacuum chamber can be a loading chamber, a vacuum transport chamber, or a process chamber.

[0016] The advantages of this invention are: by uniformly arranging embedded vacuum tubes in the vacuum chamber, and using the holes on the embedded vacuum tubes to draw dust into the embedded vacuum tubes and remove it, dust can be adsorbed from the four corners, the perimeter, and all directions of the vacuum chamber, preventing dust from falling onto the substrate.

[0017] The vacuum pipeline of the present invention has a good vacuuming effect, and during the vacuuming process, the numerous holes can also avoid the water vapor condensation phenomenon caused by the "adiabatic expansion cooling effect" in the local area near the vacuum tube in the prior art. Therefore, the vacuum pipeline structure of the present invention can increase the pumping efficiency and improve the production capacity. Attached Figure Description

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0019] Figure 1 This is a schematic diagram of the vacuum chamber structure of a chemical vapor deposition (CVD) device in the prior art.

[0020] Figure 2 Schematic diagram of the vacuum pipeline layout structure of the loading chamber in the prior art Figure 1 ; Figure 3 Schematic diagram of the vacuum pipeline layout structure of the loading chamber in the prior art Figure 2 .

[0021] Figure 4 This is a schematic diagram of the dust and water vapor structure in the loading chamber in the prior art.

[0022] Figure 5 This is a schematic diagram of a vacuum pipeline structure for improving the cleanliness of a CVD equipment vacuum system according to the present invention.

[0023] Figure 6 This is a schematic diagram of the embedded vacuum tube structure of the present invention.

[0024] Figure 7 This is a schematic diagram of the connection structure of the embedded vacuum tube, the external vacuum tube, and the first corrugated tube of the present invention. Figure 1 .

[0025] Figure 8 This is a schematic diagram of the connection structure of the embedded vacuum tube, the external vacuum tube, and the first corrugated tube of the present invention. Figure 2 .

[0026] Explanation of the labels in the diagram: 1. Vacuum chamber; 2. External vacuum tube; 3. Embedded vacuum tube; 31. Hole; 32. Flange face; 33. First bevel; 34. Second bevel; 35. Third sealing ring; 36. Fixing bolt; 4. Main vacuum tube; 5. Main vacuum valve; 6. Dry pump; 7. Auxiliary vacuum tube; 8. Auxiliary vacuum valve; 9. Connecting pipe; 10. Branch pipe; 101. Second bellows; 11. First sealing ring; 12. First bellows; 13. Second sealing ring; Detailed Implementation

[0027] Please see Figures 1 to 8 The present invention provides a vacuum pipeline structure for improving the cleanliness of the vacuum system of CVD equipment, including a vacuum chamber 1, an external vacuum tube assembly located outside the vacuum chamber 1, and an embedded vacuum tube assembly located inside the vacuum chamber 1, wherein the two ends of the embedded vacuum tube assembly are respectively connected to the external vacuum tube assembly. The embedded vacuum tube assembly is divided into two groups, and the external vacuum tube assembly is also divided into two groups. The two groups of external vacuum tube assemblies correspond one-to-one with the embedded vacuum tube assemblies. The two groups of embedded vacuum tube assemblies are located at the upper and lower ends of the vacuum chamber 1, respectively. Each group of embedded vacuum tube assemblies includes several embedded vacuum tubes 3. The embedded vacuum tubes 3 are evenly arranged inside the vacuum chamber 1. Each embedded vacuum tube 3 has a hole 31. The holes 31 are distributed on the embedded vacuum tubes 3. The holes 31 can draw dust into the embedded vacuum tubes 3 and remove it, effectively solving the problem of dust falling onto the substrate in the current technology.

[0028] When the vacuum chamber 1 is evacuated, the numerous holes 31 can also avoid the water vapor condensation phenomenon caused by the "adiabatic expansion cooling effect" in the local area near the vacuum tube in the prior art.

[0029] Adiabatic expansion refers to the process in which, during the initial stage of vacuuming, the dry pump 6 rapidly extracts gas from the chamber. The gas expands outward so quickly that it doesn't have enough time to exchange heat with the external environment (i.e., absorb or release heat). This expansion process without heat exchange is called adiabatic expansion.

[0030] Cooling: According to the laws of thermodynamics (ideal gas law and law of conservation of energy), when a gas undergoes adiabatic expansion, it needs to do work on its surroundings (pushing the piston or resisting external pressure to flow towards the pump port), but it cannot absorb heat from the outside and can only consume its own internal energy to do work. The direct manifestation of the decrease in internal energy is a sharp drop in the gas temperature.

[0031] The external vacuum tube assembly is connected to a main vacuum tube 4, and a main vacuum valve 5 is also provided on the main vacuum tube 4. A dry pump 6 is connected to the end of the main vacuum tube 4 away from the external vacuum tube assembly. The external vacuum tube assembly also includes multiple external vacuum tubes 2, and the number of external vacuum tubes 2 is twice the number of embedded vacuum tubes 3. The two ends of the embedded vacuum tubes 3 are respectively connected to the external vacuum tubes 2.

[0032] Specifically, the main vacuum tube 4 is also connected to a secondary vacuum tube 7, and a secondary vacuum valve 8 is installed on the secondary vacuum tube 7. When the vacuum chamber 1 is evacuated, the secondary vacuum valve 8 is closed and the main vacuum valve 5 is open. After the vacuum chamber 1 is evacuated, the main vacuum valve 5 is closed and the secondary vacuum valve 8 is open, so that the embedded vacuum tube maintains a negative pressure, removes dust from the vacuum chamber 1, and prevents it from falling onto the substrate.

[0033] Specifically, the diameter of the secondary vacuum tube 7 is smaller than the diameter of the main vacuum tube 4.

[0034] Specifically, the holes 31 on the embedded vacuum tube 3 are distributed in a gradient. The density of holes 31 is highest in the middle region of the embedded vacuum tube 3, and the density gradually decreases from the middle region towards the outer vacuum tube 2. As shown in the figure, the distribution of holes 31 is most dense in the middle and becomes more dispersed closer to the outer vacuum tube 2. This design can more evenly control the pumping rate of each part of the embedded vacuum tube.

[0035] Specifically, each set of external vacuum tube assemblies includes several external vacuum tubes 2, the number of which is twice the number of embedded vacuum tubes 3. The external vacuum tubes 2 are divided into two groups, located at opposite ends of the embedded vacuum tubes 3. Each group of external vacuum tubes 2 is connected via a connecting pipe 9, which is connected to a branch pipe 10. The branch pipe 10 is equipped with a flexible second corrugated pipe 101. The flexible second corrugated pipe 101 allows for adjustment of the position of the external vacuum tubes. When the embedded vacuum tubes are removed for equipment maintenance, the external vacuum tubes can move, creating space for disassembly of the embedded vacuum tubes.

[0036] Specifically, one end of the embedded vacuum tube 3 has a flange face 32, which is located outside the vacuum chamber 1 and is fastened to the outer wall of the vacuum chamber 1 by a first bolt. A first sealing ring 11 is provided between the flange face 32 and the outer wall of the vacuum chamber 1. The first sealing ring 11 is used to ensure the airtightness and vacuum level inside the vacuum chamber 1.

[0037] The outer wall of the other end of the embedded vacuum tube 3 is provided with a first oblique opening 33, and the side wall of the vacuum chamber is provided with a second oblique opening 34 corresponding to the first oblique opening 33. A third sealing ring 35 is connected between the first oblique opening 33 and the second oblique opening 34. The other end of the embedded vacuum tube 3 is also connected with a fixing bolt 36, which passes through the tube wall of the embedded vacuum tube 3 and is locked to the side wall of the vacuum chamber 1.

[0038] Specifically, each of the external vacuum tubes 2 has a first bellows 12 connected to one end facing the embedded vacuum tube 3. The inner diameter of the first bellows 12 is larger than the outer diameter of the flange face 32. The end of the first bellows 12 away from the external vacuum tube 2 is connected to the outer wall of the vacuum chamber 1, so that the flange face 32 is contained inside the first bellows 12. Both ends of the first bellows 12 are connected to the external vacuum tube 2 and the outer wall of the vacuum chamber 1 by two sets of fastening screws.

[0039] During equipment maintenance, unscrew the fastening screws to allow one end of the first corrugated pipe 12 located on both sides of the embedded vacuum tube to be removed from the outer wall of the vacuum chamber 1, exposing both ends of the embedded vacuum tube. After unscrewing the first bolt and the fixing screws, the embedded vacuum tube 3 can be removed from the vacuum chamber 1 for convenient equipment maintenance.

[0040] Specifically, a second sealing ring 13 is provided at both ends of the first bellows 12. The second sealing ring 13 is used to ensure the airtightness and vacuum level inside the vacuum chamber 1.

[0041] Specifically, the vacuum chamber 1 is a loading chamber, a vacuum transport chamber, or a process chamber.

[0042] While specific embodiments of the present invention have been described above, those skilled in the art should understand that the specific embodiments described are merely illustrative and not intended to limit the scope of the present invention. Equivalent modifications and variations made by those skilled in the art in accordance with the spirit of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A vacuum piping structure for improving the cleanliness of a CVD equipment vacuum system, characterized in that: It includes a vacuum chamber, an external vacuum tube assembly located outside the vacuum chamber, and an embedded vacuum tube assembly located inside the vacuum chamber, wherein both ends of the embedded vacuum tube assembly are connected to the external vacuum tube assembly. The embedded vacuum tube assembly is divided into two groups, which are located at the upper and lower ends of the vacuum chamber, respectively. Each group of embedded vacuum tube assemblies includes several embedded vacuum tubes, which are evenly arranged inside the vacuum chamber. Each embedded vacuum tube has a hole. The external vacuum tube assembly is connected to the main vacuum tube, which is also equipped with a main vacuum valve. The end of the main vacuum tube away from the external vacuum tube assembly is connected to a dry pump.

2. The vacuum pipeline structure for improving the cleanliness of the vacuum system in CVD equipment as described in claim 1, characterized in that: The main vacuum tube is also connected to a secondary vacuum tube, and a secondary vacuum valve is installed on the secondary vacuum tube.

3. The vacuum pipeline structure for improving the cleanliness of the vacuum system in CVD equipment as described in claim 2, characterized in that: The diameter of the secondary vacuum tube is smaller than that of the main vacuum tube.

4. The vacuum pipeline structure for improving the cleanliness of the vacuum system in CVD equipment as described in claim 1, characterized in that: The holes on the embedded vacuum tube are distributed in a gradient, with the highest density of holes in the middle region of the embedded vacuum tube, and the density of holes gradually decreases from the middle region toward the outer vacuum tube.

5. The vacuum pipeline structure for improving the cleanliness of the vacuum system in CVD equipment as described in claim 1, characterized in that: Each set of external vacuum tube assemblies includes a plurality of external vacuum tubes, the number of which is twice that of the embedded vacuum tubes. The plurality of external vacuum tubes are divided into two groups, located at the two ends of the embedded vacuum tubes respectively. Each group of external vacuum tubes is connected by a connecting pipe, and the connecting pipe is connected to a branch pipe. The branch pipe is provided with a flexible second corrugated pipe.

6. The vacuum pipeline structure for improving the cleanliness of the vacuum system in CVD equipment as described in claim 4, characterized in that: One end of the embedded vacuum tube has a flange face, which is located outside the vacuum chamber and is fastened to the outer wall of the vacuum chamber by a first bolt. A first sealing ring is provided between the flange face and the outer wall of the vacuum chamber. The outer wall of the other end of the embedded vacuum tube is provided with a first oblique opening, and the side wall of the vacuum chamber is provided with a second oblique opening corresponding to the first oblique opening. A third sealing ring is connected between the first oblique opening and the second oblique opening. The other end of the embedded vacuum tube is also connected with a fixing bolt, which passes through the tube wall of the embedded vacuum tube and is locked to the side wall of the vacuum chamber.

7. The vacuum pipeline structure for improving the cleanliness of the vacuum system in CVD equipment as described in claim 6, characterized in that: The outer vacuum tube is connected to a first bellows at the end facing the inner vacuum tube. The inner diameter of the first bellows is larger than the outer diameter of the flange face. The end of the first bellows away from the outer vacuum tube is connected to the outer wall of the vacuum chamber so as to enclose the flange face inside the first bellows.

8. The vacuum pipeline structure for improving the cleanliness of the vacuum system in CVD equipment as described in claim 7, characterized in that: The first bellows has second sealing rings at both ends.

9. A vacuum pipeline structure for improving the cleanliness of a CVD equipment vacuum system as described in claim 1, characterized in that: The vacuum chamber is a loading chamber, a vacuum transport chamber, or a process chamber.

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