Plasma enhanced chemical vapor deposition (PECVD) chamber back plate

Abstract

The utility model discloses a plasma enhanced chemical vapor deposition (PECVD) chamber back plate, which belongs to the technical field of PECVD back plates and comprises a back plate body, and the back plate body comprises a gas inlet side and a gas outlet side. The main air channel is arranged in the middle of the back plate body, and the main air channel penetrates through the air inlet side and the air outlet side; the main air channel comprises an air inlet channel and an air outlet channel, and the air inlet channel is communicated with the air outlet channel; one end of each branch air channel is communicated with the air inlet channel, and the other end of each branch air channel is communicated with the air outlet side; and the plurality of branch air passages are arranged in a scattering manner around the main air passage as a center when being observed from the air inlet side. The diffusion radius of gas can be enlarged, the diffusion distance is shortened compared with a single main gas channel structure, and the gas consumption can be reduced while the same diffusion effect is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of PECVD back plates, in particular to a PECVD chamber back plate. Background Art

[0002] In the manufacturing process of liquid crystal display panels, a plasma enhanced chemical vapor deposition process is required. Plasma enhanced chemical vapor deposition (PECVD) technology is a method for preparing semiconductor thin film materials and other material films by ionizing them in a deposition chamber using glow discharge and then chemically depositing them on a substrate. It enhances the activity of chemical vapor reaction substances through plasma activation, increases the surface reaction rate, and significantly reduces the film deposition temperature through high-energy ions.

[0003] In plasma enhanced chemical vapor deposition, the backing plate is the most important component in the plasma enhanced chemical vapor deposition chamber. It acts as a passage for gas to pass before the gas is ejected through the diffuser. Existing backing plates widely use a middle channel as a passage for gas to pass through. The gas diffuses to other components over a long distance through the middle channel. If you want to achieve the purpose of sufficient gas diffusion, you need to consume a lot of gas.

[0004] There are also plans to improve the backplane air duct. For example, a Chinese patent document with announcement number CN203700512U discloses a plasma enhanced chemical vapor deposition chamber. Several channels are set in the backplane, and the ends of the channels are connected by hoses to form a continuous path. Although the continuous path can make the gas diffuse fully, the continuous path also increases the gas stroke and, to a certain extent, also increases the gas diffusion distance, resulting in unnecessary gas consumption. Utility Model Content

[0005] The utility model aims to provide a PECVD chamber back plate, which solves the problem in the prior art that the back plate uses a middle channel as a passage for gas to pass through, and the gas diffuses to other components through the middle channel over a long distance, resulting in gas waste.

[0006] In order to achieve the above-mentioned object, the utility model provides a PECVD chamber back plate, comprising a back plate body, wherein the back plate body comprises an air inlet side and an air outlet side;

[0007] A main air duct is arranged in the middle of the back plate body, and the main air duct runs through the air inlet side and the air outlet side;

[0008] The main air passage comprises an air inlet passage and an air outlet passage, and the air inlet passage and the air outlet passage are in communication;

[0009] It also includes a plurality of bronchial passages, one end of which is connected to the air inlet passage, and the other end of which is connected to the air outlet side; observed from the air inlet side, the plurality of bronchial passages are arranged in a scattered manner with the main airway as the center.

[0010] Furthermore, the included angles of adjacent bronchi are equal or unequal.

[0011] Furthermore, when viewed from the air intake side, the plurality of tributaries are arranged in a cross shape or a crisscross shape.

[0012] Furthermore, the diameter of the airway inlet of the main airway is greater than the diameter of the bronchial airway.

[0013] Furthermore, a transition air duct is provided between the air inlet and the air outlet of the main air duct, and the diameter of the transition air duct is smaller than the diameter of the air inlet.

[0014] Furthermore, the air outlet is arranged in a trumpet shape, and the trumpet mouth is located at the air outlet side.

[0015] Furthermore, a first step hole is provided on the outlet side at the bell mouth position of the outlet duct, and the first step hole surrounds the outer side of the bell mouth.

[0016] Furthermore, the air inlet side is provided with a plurality of flange holes on the outer side of the main air passage.

[0017] Furthermore, the air outlet side is provided with a second step hole at the outlet corresponding to each bronchus, and the second step hole is arranged around the outer side of the outlet of the bronchus.

[0018] Furthermore, the shape of the second step hole is the same as the shape of the bronchial outlet, which is an ellipse.

[0019] Compared with the existing known technologies, the technical solution provided by the utility model has the following beneficial effects:

[0020] (1) The utility model provides a PECVD chamber back plate. After the gas enters from the main airway, part of the gas enters a plurality of branch airways connected to the main airway. The plurality of branch airways scatter around the main airway. The gas can diffuse through the main airway and the branch airways together. Under the guidance of the branch airways, the gas can be fully diffused to other component positions, thereby expanding the diffusion radius of the gas and shortening the diffusion distance relative to a single central main airway structure. The amount of gas used can be reduced while achieving the same diffusion effect.

[0021] (2) The utility model provides a PECVD chamber back plate, wherein a plurality of branch airways are scattered around the main airway, and the gas can be sprayed from the center or to the surrounding areas, thereby solving the problem of uneven spraying in the prior art in which the gas volume is high in the middle and low around the surrounding areas during the gas spraying process.

[0022] (3) In a PECVD chamber back plate of the utility model, the diameter of the air inlet of the main airway is larger than the diameter of the bronchial airway, and the air inlet can have sufficient space to accommodate gas, so that after the gas enters the main airway, a sufficient amount of gas can be diverted into the bronchial airway, and the remaining gas in the air inlet can enter the air outlet, ensuring that the gas can diffuse from the main airway and the bronchial airway together.

[0023] (4) In a PECVD chamber back plate of the utility model, the diameter of the transition gas channel is smaller than the diameter of the inlet channel. The smaller diameter of the transition gas channel can increase the flow rate of the gas in the transition gas channel. The outlet channel is arranged in a trumpet shape. When the gas is ejected through the outlet channel, the injection radius of the gas can be increased, thereby improving the diffusion efficiency of the gas.

[0024] It will be apparent that elements or features described above in the context of a single embodiment may be used alone or in combination in other embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In the drawings, the sizes and proportions do not represent the sizes and proportions of actual products. The drawings are merely illustrative, and some non-essential elements or features are omitted for clarity.

[0026] Figure 1 It is a schematic diagram of the air outlet side structure of the back plate body of the embodiment of the utility model;

[0027] Figure 2 yes Figure 1 A schematic diagram of the cross-sectional structure at A-A';

[0028] Figure 3 yes Figure 1 A schematic diagram of the cross-sectional structure at the B-B' position;

[0029] Figure 4 yes Figure 1 Schematic diagram of the cross-sectional structure at Z-Z'.

[0030] Description of Reference Numerals

[0031] 100, back plate body; 110, air inlet side; 120, air outlet side; 200, main air duct; 210, air inlet duct; 220, transition air duct; 230, air outlet duct; 240, first step hole; 300, branch air duct; 310, second step hole. DETAILED DESCRIPTION

[0032] The present invention will be described in detail with reference to the accompanying drawings. What is described here is only a preferred embodiment of the present invention, and those skilled in the art can think of other ways to implement the present invention based on the preferred embodiment, and other ways also fall within the scope of the present invention.

[0033] Example

[0034] Reference Figure 1-Figure 4 The present embodiment provides a PECVD chamber back plate, including a back plate body 100, the back plate body 100 includes an air inlet side 110 and an air outlet side 120; a main air duct 200, which is arranged in the middle of the back plate body 100, and the main air duct 200 runs through the air inlet side 110 and the air outlet side 120; the main air duct 200 includes an air inlet duct 210 and an air outlet duct 230, and the air inlet duct 210 and the air outlet duct 230 are connected; it also includes a plurality of branch air ducts 300, one end of the branch air duct 300 is connected to the air inlet duct 210, and the other end is connected to the air outlet side 120; observed from the air inlet side 110, the plurality of branch air ducts 300 are arranged in a scattered manner around the main air duct 200 as the center.

[0035] In this embodiment, after the gas enters from the main airway 200, part of the gas enters a plurality of tributaries 300 connected to the main airway 200, and the plurality of tributaries 300 are scattered around with the main airway 200 as the center, and the gas can diffuse through the main airway 200 and the tributaries 300 together, and can be fully diffused to other parts under the guidance of the tributaries 300, thereby expanding the diffusion radius of the gas and reducing the diffusion distance relative to the single central main airway 200 structure, and can reduce the amount of gas used when achieving the same diffusion effect. On the other hand, the plurality of tributaries 300 are scattered around with the main airway 200 as the center, and the gas can be sprayed from the center or to the surroundings, which solves the problem of uneven spraying in the prior art in which the gas volume is high in the middle and low around during the gas spraying process.

[0036] Furthermore, Figure 1 , Figure 2 As shown, the so-called scattering shape is that the eight air ducts 300 are arranged in a cross shape when viewed from the air intake side 110. The air ducts 300 are all linear pipe structures. The cross shape arrangement structure can increase the diffusion radius of the gas. It should be noted that the arrangement of the air ducts 300 is not limited to the cross shape structure, and a cross shape or other shape structures can also be adopted. The shape structure is mainly affected by the number of air ducts 300, and the purpose is to expand the scattering radius of the gas.

[0037] For gas diffusion uniformity considerations, please refer to Figure 1In this embodiment, the angles between adjacent bronchi 300 are equal. When the angles between adjacent bronchi 300 are equal, the regularly shaped backplane body 100 can be evenly divided, and when the gas is ejected from the bronchi 300, it can be evenly diffused to the corresponding places, and the diffusion uniformity is better. It should be noted that when the shape of the backplane body 100 is irregular, the angles between adjacent bronchi 300 may be different. In places where concentrated gas injection is required, the angles between adjacent bronchi 300 can be reduced accordingly, the number of bronchi 300 can be increased, and the injection amount can be increased.

[0038] In this embodiment, please refer to Figure 2 , Figure 3 and Figure 4 , the diameter of the air inlet 210 of the main airway 200 is larger than the diameter of the bronchial 300. The larger diameter of the air inlet 210 of the main airway 200 allows the air inlet 210 to have enough space to accommodate gas, and after the gas enters the air inlet 210, a sufficient amount of gas is diverted to enter the bronchial 300, and the remaining gas in the air inlet 210 enters the air outlet 230, ensuring that the gas can diffuse from the main airway 200 and the bronchial 300 together. The main airway 200 and the bronchial 300 form a gas diffusion network to improve the gas diffusion efficiency.

[0039] Further design solutions can also be used to improve the gas diffusion efficiency. In this embodiment, please continue to refer to Figure 2 , Figure 3 and Figure 4 A transition air duct 220 is provided between the air inlet duct 210 and the air outlet duct 230 of the main air duct 200, and the diameter of the transition air duct 220 is smaller than the diameter of the air inlet duct 210. The smaller diameter of the transition air duct 220 can increase the flow rate of the gas in the transition air duct 220. The air outlet duct 230 is arranged in a trumpet shape, and the trumpet mouth is located at the air outlet side 120. The air outlet duct 230 is arranged in a trumpet shape, and when the gas is ejected through the air outlet duct 230, the injection radius of the gas can be increased, thereby improving the diffusion efficiency of the gas.

[0040] The back plate body 100 is not an isolated component, and needs to be used in conjunction with other components in the PECVD chamber. Figure 1 and Figure 2As shown, the outlet side 120 of the back plate body 100 is provided with a first step hole 240 at the bell mouth position of the outlet duct 230, and the first step hole 240 surrounds the outside of the bell mouth. The air inlet side 110 is provided with a plurality of flange holes on the outside of the main air duct 200. The outlet side 120 is provided with a second step hole 310 at the outlet corresponding to each branch duct 300, and the second step hole 310 is arranged around the outside of the outlet of the branch duct 300. The shape of the second step hole 310 is the same as the outlet shape of the branch duct 300, which is elliptical. The first step hole 240, the flange hole and the second step hole 310 can facilitate the assembly of the back plate body 100 with other components and help the gas diffuse into other components.

[0041] In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "front", "rear", "left", "right", "up", "down", "top", "bottom", "inside", "outside", etc. are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, 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 used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0042] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" 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 it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0043] The protection scope of the present invention is limited only by the claims. Thanks to the teachings of the present invention, those skilled in the art will easily recognize that alternative structures to the structures disclosed in the present invention can be used as feasible alternative embodiments, and the embodiments disclosed in the present invention can be combined to generate new embodiments, which also fall within the scope of the appended claims.

Claims

1. A PECVD chamber back plate, comprising: A back plate body (100), the back plate body (100) comprising an air inlet side (110) and an air outlet side (120); A main air passage (200) is arranged in the middle of the back plate body (100), and the main air passage (200) is arranged through the air inlet side (110) and the air outlet side (120); It is characterized in that The main air passage (200) comprises an air inlet passage (210) and an air outlet passage (230), and the air inlet passage (210) and the air outlet passage (230) are in communication; It also includes a plurality of bronchial passages (300), one end of each bronchial passage (300) being connected to the air inlet passage (210), and the other end of each bronchial passage (300) being connected to the air outlet side (120); when viewed from the air inlet side (110), the plurality of bronchial passages (300) are arranged in a scattered manner with the main airway (200) as the center.

2. A PECVD chamber back plate according to claim 1, characterized in that: The included angles of adjacent bronchi (300) are equal or different.

3. A PECVD chamber back plate according to claim 1, characterized in that: When viewed from the air inlet side (110), the plurality of branch passages (300) are arranged in a cross shape or a crisscross shape.

4. A PECVD chamber back plate according to claim 1, characterized in that: The diameter of the air inlet (210) of the main airway (200) is greater than the diameter of the bronchial airway (300).

5. A PECVD chamber back plate according to claim 4, characterized in that: A transition air duct (220) is provided between the air inlet duct (210) and the air outlet duct (230) of the main air duct (200), and the diameter of the transition air duct (220) is smaller than the diameter of the air inlet duct (210).

6. A PECVD chamber back plate according to claim 5, characterized in that: The air outlet (230) is arranged in a trumpet shape, and the trumpet mouth is located at the air outlet side (120).

7. A PECVD chamber back plate according to claim 6, characterized in that: The outlet side (120) is provided with a first step hole (240) at the bell mouth position of the outlet passage (230), and the first step hole (240) surrounds the outer side of the bell mouth.

8. The PECVD chamber back plate according to claim 1, characterized in that: The air inlet side (110) is provided with a plurality of flange holes on the outside of the main air passage (200).

9. The PECVD chamber back plate according to claim 1, characterized in that: The air outlet side (120) is provided with a second step hole (310) at the outlet corresponding to each bronchus (300), and the second step hole (310) is arranged around the outside of the outlet of the bronchus (300).

10. A PECVD chamber back plate according to claim 9, characterized in that: The shape of the second step hole (310) is the same as the shape of the outlet of the bronchus (300), which is an ellipse.

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