Manufacturing method for improving gas uniformity distribution of key part Back Plate in cavity applied to PECVD (Plasma Enhanced Chemical Vapor Deposition) process in display industry

Abstract

The invention discloses a manufacturing method for improving gas uniformity distribution of a key part Back Plate in a cavity applied to a PECVD (Plasma Enhanced Chemical Vapor Deposition) manufacturing process in the display industry, which belongs to the field of the display industry and comprises the following steps: designing a Back Plate structure, manufacturing a processing tool, treating the inner surface of a hole, verifying the effect and assembling, designing a main pipeline gas inlet shrinking structure, and designing a main pipeline gas inlet shrinking structure. The diameter of a main pipeline is reduced through the vacuum welding technology so as to increase the gas flow rate, pressure difference control is achieved based on the Bernoulli principle, a plurality of large-angle inclined hole branch pipelines are designed, the number of inclined holes is eight, and the inclined holes are evenly distributed in the periphery of a Back Plate. According to the manufacturing method for improving the gas uniformity distribution of the key part Back Plate in the cavity applied to the PECVD process in the display industry, the gas distribution uniformity is remarkably improved, the film thickness non-uniformity U% is reduced to a target value of less than or equal to 3.5%, the process gas consumption is effectively reduced, the cost is saved, and the product quality is improved through high-precision design and surface treatment. And the process reliability and the efficiency are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of display industry, and in particular to a manufacturing method for improving the gas uniformity distribution of a key part in a cavity of a PECVD process applied to the display industry. BACKGROUND

[0002] The key part in the cavity of the PECVD process is an indispensable part in the production of display panels. In large-scale display panel manufacturing, the gas uniformity of the PECVD cavity directly determines the consistency of the film thickness, and further affects the device yield and optical performance.

[0003] The traditional Back Plate design adopts a single central main pipeline gas inlet structure, and the gas is directly injected into the cavity from the center. This design leads to insufficient diffusion of the gas at the edge of the cavity, forming a clear "center enrichment-edge sparseness" distribution pattern, which can cause uneven gas diffusion, too high gas concentration in the central area, and insufficient reaction gas partial pressure at the edge, resulting in a film thickness difference (U%) as high as 8.3%, low reaction efficiency, long gas residence time in the edge area, and serious waste of unreacted gas, especially the increase in the loss of expensive process gases such as NF3, and the limitation of processing precision, making it difficult for existing tooling to ensure the consistency of the multi-bevel hole angle and the surface finish, further exacerbating gas turbulence. SUMMARY

[0004] To solve the problems raised in the background art, the present application provides a manufacturing method for improving the gas uniformity distribution of a key part in a cavity of a PECVD process applied to the display industry.

[0005] The manufacturing method for improving the gas uniformity distribution of a key part in a cavity of a PECVD process applied to the display industry provided by the present application adopts the following technical solution:

[0006] A manufacturing method for improving the gas uniformity distribution of a key part in a cavity of a PECVD process applied to the display industry, comprising the following steps:

[0007] S1, Back Plate structure design:

[0008] S101, design a main pipeline gas inlet narrowing structure, use vacuum welding technology to narrow the main pipeline diameter to increase the gas flow rate, and realize pressure difference control based on Bernoulli's principle;

[0009] S102, design multiple large-angle inclined hole branch pipes, the number of inclined holes is 8, which are evenly distributed on the periphery of the Back Plate, and the outlet is adjusted to the central position of the cavity to enhance the gas diffusion speed and the key gas reaction partial pressure P;

[0010] S2, process tool manufacturing:

[0011] S201, design a special tool clamp for fixing the Back Plate and ensuring the flatness of the inclined hole processing;

[0012] S202, use the tool to process inclined holes to ensure that all inclined hole angles are consistent, with a flatness error of ≤0.05mm;

[0013] S3, hole inner surface treatment:

[0014] S301, grind and polish the inner surface of the inclined hole, adopt multi-stage grinding process, target smoothness ≥650 GU;

[0015] S302, detect the smoothness after polishing to ensure that the surface roughness Ra≤0.1μm;

[0016] S4, effect verification and assembly:

[0017] S401, test gas uniformity in CVD coating process, monitor film thickness uniformity U%;

[0018] S402, optimize parameters according to test results, assemble the Back Plate to the PECVD cavity.

[0019] Preferably, the large-angle inclined hole design in S102 has an inclined hole angle range of 45°-60°, an inclined hole length ≥1500mm, and a hole spacing design that satisfies a gas diffusion radius ≥15m.

[0020] Preferably, the tool clamp in S201 is made of high-strength aluminum alloy, including an adjustable clamping module to adapt to different Back Plate sizes, with a clamping force control range of 50-100N.

[0021] Preferably, the grinding and polishing process in S301 includes three stages of rough grinding, fine grinding and super-fine polishing, using diamond abrasive, with a grinding pressure of 0.5-2MPa, and a polishing time controlled within 30-60 minutes.

[0022] Preferably, the gas uniformity test in S401 controls the non-uniformity U% to ≤3.5%, which is verified by DUMMY sheet test data.

[0023] Preferably, the main pipe in S101 is reduced in size, with a reduction ratio of 50-70% of the original diameter, and a gas flow rate increase rate ≥40% based on the Bernoulli equation Parameter optimization is performed, where p is the gas density, v is the flow rate, g is the acceleration of gravity, h is the height, and C is a constant.

[0024] Preferably, the inclined hole branch pipe in S102 adds calcium-based bentonite as an expanding agent to the gas flow path at a dosage of 3-5% to compensate for the closed space of the interlayer and improve diffusion uniformity.

[0025] In summary, the present application includes the following beneficial technical effects:

[0026] 1. Significantly improve gas distribution uniformity, reduce film thickness unevenness U% to ≤3.5%: By optimizing the Back Plate structure, this method significantly improves the uniformity of gas in the CVD coating process. Based on the actual test data in document 2, U% is reduced from 8.3% before improvement to less than 3.5%, which ensures the consistency of film thickness, reduces process variation, and improves the film thickness distribution, which improves the film yield by about 10% and reduces the rework rate;

[0027] 2. Effectively reduce process gas consumption and achieve cost savings: This method adds calcium-based bentonite as an expanding agent in the inclined hole branch pipe of S102 to compensate for the closed space of the interlayer and improve gas diffusion uniformity. This improvement significantly reduces the waste of NF3 and other reaction gases, and by optimizing the gas flow path, the gas utilization rate is increased by about 20%, resulting in a process cost reduction of about 15%. This not only meets the energy-saving and environmental protection requirements, but also enhances the long-term economy of PECVD equipment;

[0028] 3. Ensure process reliability and efficiency improvement through high-precision design and surface treatment: This method combines the special tooling fixture of S201 and the multi-stage grinding and polishing process of S301 to ensure the machining precision of the Back Plate, and the uniformity of gas dispersion after modification avoids the concentration problem of the original design. This design optimization enhances the gas diffusion speed and increases the key reaction partial pressure P by about 15%, thereby improving the overall efficiency of the PECVD process and reducing the equipment maintenance frequency. BRIEF DESCRIPTION OF DRAWINGS

[0029] Fig. 1 is a flowchart of a manufacturing method for improving the gas uniformity distribution of the key part Back Plate in the cavity of the PECVD process in the display industry in the embodiments of the present application;

[0030] Fig. 2This is a thickness data table of CVD film thickness coating uniformity in a manufacturing method for improving the gas uniformity distribution of BackPlate, a key component in the cavity of a PECVD process in the display industry, as described in an embodiment of this application.

[0031] Fig. 3 This is a schematic diagram of BP gas dispersion in an embodiment of the present application of a manufacturing method for improving the uniformity of gas distribution in the BackPlate, a key component in the cavity of a PECVD process in the display industry. Detailed Implementation

[0032] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] like Figs. 1-3 According to an embodiment of the present invention, a manufacturing method for improving the gas uniformity distribution of a key component, the Back Plate, in a cavity of a PECVD process in the display industry includes the following steps:

[0034] S1, Back Plate structural design:

[0035] S101. Design a reduced structure for the main pipeline air inlet, use vacuum welding technology to reduce the diameter of the main pipeline to increase the gas flow rate, and achieve pressure difference control based on Bernoulli's principle.

[0036] S102. Design multiple large-angle inclined branch pipes with a total of 8 inclined holes, evenly distributed around the Back Plate. Adjust the outlet to the center of the cavity to enhance the gas diffusion rate and the partial pressure P of the key gas reaction.

[0037] S2. Manufacturing of machining tools:

[0038] S201. Design a special tooling fixture to fix the back plate and ensure the flatness of the inclined hole machining;

[0039] S202. Use this tooling to machine oblique holes, ensuring that all oblique holes have the same angle and a flatness error of ≤0.05mm.

[0040] S3. Hole internal surface treatment:

[0041] S301. Grind and polish the inner surface of the inclined hole using a multi-stage grinding process, with a target surface finish ≥650 GU.

[0042] S302, detect the smoothness after polishing to ensure that the surface roughness Ra≤0.1 μm;

[0043] S4, effect verification and assembly:

[0044] S401, test the gas uniformity in the CVD coating process, and monitor the film thickness non-uniformity U%;

[0045] S402, optimize the parameters according to the test results, and assemble the Back Plate to the PECVD cavity.

[0046] In this embodiment, the large-angle inclined hole in S102 is designed, the inclined hole angle range is 45°-60°, the inclined hole length≥1500mm, and the hole spacing design satisfies the gas diffusion radius≥15m.

[0047] Specifically, the large-angle inclined hole design significantly improves the gas diffusion efficiency by adjusting the outlet to the central position of the cavity, the inclined angle of 45°-60° optimizes the gas flow direction, reduces the turbulent flow, and at the same time, the diffusion radius≥15m ensures the uniform coverage of the gas in the large cavity. This design increases the key reaction partial pressure P by about 15%, reduces the local variation of film deposition. After the reform, the gas dispersion is more uniform, avoiding the concentration problem of the original design.

[0048] In this embodiment, the tool clamp in S201 is made of high-strength aluminum alloy, which contains an adjustable clamping module to adapt to different Back Plate sizes, and the clamping force control range is 50-100N.

[0049] Specifically, the high-strength aluminum alloy material of the tool clamp provides excellent rigidity and lightweight characteristics, ensuring stability during processing, and the adjustable clamping module allows the Back Plate to be adapted to 60K to 80K sizes, and the precise control of clamping force 50-100N prevents workpiece deformation, thereby ensuring the flatness of inclined hole processing≤0.05mm. This design significantly improves the processing efficiency, reduces the clamp replacement time by about 30%, and is suitable for high-precision mass production.

[0050] In this embodiment, the grinding and polishing process in S301 includes three stages of rough grinding, fine grinding and super fine polishing, uses diamond abrasive, the grinding pressure is 0.5-2MPa, and the polishing time is controlled within 30-60 minutes.

[0051] Specifically, the three-stage grinding and polishing process removes surface defects by rough grinding, smoothens microscopic unevenness by fine grinding, and achieves a target smoothness of ≥650 GU by super-fine polishing. Diamond abrasives ensure efficient processing of high-hardness surfaces. A pressure of 0.5-2 MPa and a time window of 30-60 minutes optimize material removal rate while avoiding damage to the hole wall. After this treatment, the surface roughness Ra≤0.1 μm significantly reduces gas flow resistance and improves deposition uniformity, making it suitable for long and inclined holes of 1500 mm or more.

[0052] In this embodiment, the gas uniformity test in S401 has a non-uniformity U% control target of ≤3.5%, which is verified by DUMMY sheet test data.

[0053] Specifically, the gas uniformity test uses DUMMY sheets for multi-point monitoring, and the U% target is ≤3.5%, which is achieved by statistical film thickness data. This is a significant reduction from the previous 8.3% U%, reducing rework rates and improving PECVD process yield by about 10%.

[0054] In this embodiment, the main pipeline narrowing structure in S101 has a narrowing ratio of 50%-70% of the original diameter, and the gas flow rate increases by ≥40%. Based on Bernoulli's equation Parameter optimization is performed, where ρ is the gas density, v is the flow rate, g is the acceleration of gravity, h is the height, and C is a constant.

[0055] Specifically, the main pipeline narrowing structure increases the gas flow rate by ≥40% based on the Bernoulli principle, with a narrowing ratio of 50%-70%, achieving differential pressure control in the central region, thereby optimizing gas distribution, reducing gas residence time, and improving reaction efficiency. Dynamic parameter calibration is based on the equation pv² + pgh = C.

[0056] In this embodiment, the inclined hole branch pipeline in S102 adds an expanding agent, calcium-based bentonite, to the gas flow path at a dosage of 3%-5% to compensate for the closed space of the separation layer and improve diffusion uniformity.

[0057] Specifically, the addition of calcium-based bentonite expanding agent (dosage 3%-5%) in the gas flow path effectively fills the microscopic separation layer space, reducing gas leakage and uneven diffusion. This additive compensates for the closed gap through its water absorption and swelling properties, improving diffusion uniformity by about 20%.

[0058] In the embodiments of the present application, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other ways. For example, the above-described device embodiments are merely illustrative. For example, the division of the modules is merely a logical function division. There can be another division manner in actual implementation. The modules illustrated as separate components can or can not be physically separate, and the components illustrated as modules can or can not be physical units. That is, they can be located in one place or distributed on a plurality of network units. According to actual needs, some or all of the modules can be selected to achieve the purpose of the method of the embodiments.

[0059] The above embodiments are only used to illustrate but not limit the technical method of the present application. Although the technical method of the present application is described in detail with reference to the preferred embodiments, it should be understood by those of ordinary skill in the art that the technical method of the present application can be modified or equivalently replaced without departing from the spirit and scope of the technical method of the present application.

Claims

1. A manufacturing method for improving the gas uniformity distribution of a back plate, which is a key component in a chamber used in the PECVD process in the display industry, characterized by: The method comprises the following steps: S1, Back Plate structure design: S101, design main pipe inlet narrowing structure, use vacuum welding technology to narrow the main pipe diameter to increase gas flow rate, and realize pressure difference control based on Bernoulli principle; S102, design multiple large-angle inclined hole branch pipes, the number of inclined holes is 8, which are evenly distributed on the periphery of the Back Plate, and the outlet is adjusted to the central position of the cavity to enhance the gas diffusion speed and key gas reaction partial pressure P; S2, processing tool manufacturing: S201, design a special tool clamp for fixing the Back Plate and ensuring the flatness of inclined hole processing; S202, use the tool to process inclined holes to ensure that all inclined hole angles are consistent, with a flatness error of ≤0.05mm; S3, hole inner surface treatment: S301, grind and polish the inner surface of the inclined hole, adopt multi-stage grinding process, target smoothness ≥650 GU; S302, detect the smoothness after polishing to ensure that the surface roughness Ra≤0.1μm; S4, effect verification and assembly: S401, test gas uniformity in CVD coating process, monitor film thickness non-uniformity U%; S402, optimize parameters according to test results, assemble Back Plate to PECVD cavity.

2. The manufacturing method for improving the gas uniformity distribution of the BackPlate, a key component in the cavity of a PECVD process in the display industry, as described in claim 1, is characterized in that: The large-angle inclined hole design in S102 has an inclined hole angle range of 45°-60°, an inclined hole length ≥1500mm, and a hole spacing design that satisfies a gas diffusion radius ≥15m.

3. The manufacturing method for improving the gas uniformity distribution of the BackPlate, a key component in the cavity of a PECVD process in the display industry, as described in claim 1, is characterized in that: The tool clamp in S201 is made of high-strength aluminum alloy and contains adjustable clamping modules to adapt to different Back Plate sizes, with a clamping force control range of 50-100N.

4. The manufacturing method of claim 1, wherein the method is applied to improve the gas uniformity distribution of the BackPlate, which is a key component in the chamber of the PECVD process in the display industry. The grinding and polishing process in S301 includes three stages of rough grinding, fine grinding and super-fine polishing, uses diamond abrasive, grinding pressure is 0.5-2MPa, and polishing time is controlled within 30-60 minutes.

5. The manufacturing method of claim 1, wherein the method is applied to improve the gas uniformity distribution of the BackPlate, which is a key component in the chamber of the PECVD process in the display industry. The gas uniformity test in S401 controls the non-uniformity U% to ≤3.5%, which is verified by DUMMY sheet test data.

6. The manufacturing method of claim 1, wherein the method is applied to improve the gas uniformity distribution of the BackPlate, which is a key component in the chamber of the PECVD process in the display industry. The main pipe reducing structure in S101 reduces the ratio of 50%-70% of the original diameter, and the gas flow rate increases by ≥40%, based on Bernoulli equation Parameter optimization is performed, where p is the gas density, v is the flow rate, g is the acceleration of gravity, h is the height, and C is a constant.

7. The manufacturing method of claim 1, wherein the method is applied to improve the gas uniformity distribution of the BackPlate, which is a key component in the chamber of the PECVD process in the display industry. The inclined hole branch pipe in S102 adds calcium-based bentonite as an expanding agent in the gas flow path at a dosage of 3%-5% to compensate for the separation closure space and improve diffusion uniformity.

Images