Metal plate design and cleaning method for cleaning etching chamber

Abstract

The invention provides a metal plate design and cleaning method for cleaning an etching chamber, and relates to the technical field of plasma cleaning, and the method comprises the following steps: designing a low-sputtering-yield metal film on four sides of an aluminum plate, controlling the width and thickness of the metal film to enable the metal film to be suitable for sputtering regulation and shielding, and pressing the metal film through an insulating pressing plate to enable the metal film to be partially exposed; after inert gas plasma bombardment, potential particles are deposited and covered, and an edge film layer diffracts to be thinned and is not prone to falling off. According to the invention, the films with low sputtering yield, including Ti, W and Ta, are designed on the four sides of the metal aluminum plate for cleaning the etching chamber, and the sputtering yield of the films with low sputtering yield is only 30%-40% of that of an Al film, so that when the etching chamber executes the cleaning operation of the metal aluminum plate, the films with low sputtering yield are diffracted on the edges of the insulating pressing edges, and the diffracted metal film layers are thinned, so that the etching efficiency is improved. And the problem of film layer falling is not easy to occur. The service life of the insulation pressing edge is prolonged, and the edge sparking risk is reduced at the same time.

Description

Technical Field

[0001] This invention relates to the field of plasma cleaning technology, and in particular to the design of a metal plate and a cleaning method for cleaning etching chambers. Background Technology

[0002] Plasma etching chambers typically use one or more gases to generate plasma, free radicals, or other substances to remove materials. In some applications, physical methods are used for material removal. For example, in the pre-cleaning process before seed layer sputtering in advanced packaging, inert gases such as argon are often used to remove metal oxides from the metal surface at the bottom of the holes. This reduces the contact resistance between the seed layer metal film and the underlying metal layer during subsequent deposition. During this process, the dielectric layer on the metal surface, such as polyimide, epoxy resin, ABF, or other organic films, is also removed. However, because this process uses physical etching, large particles from the organic film adhere to the electrodes and the chamber walls, causing particle contamination of the processed substrate.

[0003] A cleaning method (CN113936989A - Cleaning method for reaction chamber of plasma etching equipment and wafer etching method) has been proposed. After etching a certain number of products, an aluminum plate is placed in the chamber and bombarded to form aluminum atoms. The aluminum atoms are deposited on the inner wall of the reaction chamber to form an aluminum film. The formation of this aluminum film covers the reaction byproducts deposited on the reaction chamber wall, avoiding the influence of byproducts on subsequent etching processes and reducing particle contamination. However, in practical applications, because the insulating edge is in contact with the aluminum plate, the aluminum film diffracted at its edge is thicker, which easily leads to film peeling and arcing problems, affecting its service life. Summary of the Invention

[0004] The purpose of this invention is to solve the technical problems mentioned in the background section.

[0005] The present invention adopts the following technical solution: a metal plate design and cleaning method for cleaning etching chambers, comprising the following steps:

[0006] S1: Design a low sputtering yield metal film on the four sides of an aluminum plate, the metal film including at least one of titanium, tungsten, and tantalum, the metal film having a significantly lower sputtering yield compared to aluminum material;

[0007] S2: Control the width and thickness of the low-sputtering-yield film to make it suitable for the material control and shielding requirements in the subsequent sputtering process;

[0008] S3: The aluminum plate is conveyed to the substrate stage in the etching chamber, and the edge of the aluminum plate is pressed by an insulating plate, so that the insulating plate comes into contact with the low sputtering yield film and a portion of the low sputtering yield film is exposed to the outside.

[0009] S4: By bombarding the surface of the aluminum plate with inert gas plasma, aluminum atoms and low sputtering yield metal atoms are sputtered from the surface and deposited onto the inner wall of the etching chamber and the surface of related components, thereby covering or encapsulating potential particles and reducing the risk of particle diffusion.

[0010] S5: The film thickness is reduced by the low sputtering yield film diffracted onto the pressure plate pressing area, which reduces the risk of film peeling and extends the service life of the insulating edge pressing.

[0011] Preferably, the thickness of the aluminum plate is between 0.5 mm and 4.0 mm. Here, controlling the thickness range of the aluminum plate, while ensuring structural strength and deformation control, is beneficial for achieving good mechanical support performance, facilitating processing and transportation, matching the energy deposition efficiency required for plasma bombardment, and improving material utilization and cleaning effect.

[0012] Preferably, the aluminum plate has a rectangular structure with dimensions consistent with the produced substrate and a side length greater than 200mm. This matches the substrate size used in the actual process (including standard wafer or panel sizes), allowing for seamless integration into existing equipment processes and improving adaptability and versatility. The larger side length also increases the coverage per unit area, improving particle coating efficiency.

[0013] Preferably, the low sputtering yield metal film is made of titanium, and the thickness of the metal film is 1 μm. Here, titanium has good low sputtering yield characteristics and stable adhesion performance, which can significantly reduce the material sputtering rate in the edge region; the 1 μm thickness can ensure that the film layer maintains stable coverage under plasma bombardment, while avoiding material waste and balancing cost and durability.

[0014] Preferably, the low-sputtering-yield metal thin film is deposited using a magnetron sputtering process. Here, magnetron sputtering has advantages such as high film uniformity, dense film quality, and strong adhesion, ensuring that the metal thin film forms a stable coating layer on the edge of the aluminum plate, thereby improving the consistency and reliability of cleaning the metal plate from the source.

[0015] Preferably, the edge width between the insulating pressure plate and the aluminum plate is 1mm to 5mm. Here, by reasonably designing the edge width, it is possible to ensure that the pressure plate firmly presses against the edge of the aluminum plate, while avoiding the risk of film peeling due to excessively wide edge width. At the same time, it maximizes the exposure of the effective sputtering area, which is beneficial to improving the overall sputtering coverage efficiency.

[0016] Preferably, the insulating pressure plate is made of quartz or ceramic. Here, quartz and ceramic have excellent heat resistance and electrical insulation properties, and can withstand the plasma process environment for a long time without deterioration. At the same time, their smooth surface helps to avoid mechanical damage to the metal film, and iteratively improves the edge life and film stability.

[0017] Preferably, the inert gas is argon, and the plasma is argon plasma, used to sputter aluminum atoms and low-yield metal atoms and deposit them onto the inner wall of the chamber and the surface of the workpiece. Here, using argon plasma can stably provide a high-energy ion source, effectively sputtering aluminum and metal atoms without introducing additional chemical reactions to form a coating layer on the particles. At the same time, it is safe to operate, has low gas source cost, and is suitable for batch industrial applications.

[0018] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0019] In this invention, low-sputtering-yield thin films, including Ti, W, and Ta, are designed on the four sides of the aluminum plate used for etching chamber cleaning. Since the sputtering yield of these low-sputtering-yield films is only 30% to 40% of that of Al films, the insulating edge of the etching chamber is coated with the low-sputtering-yield film during the aluminum plate cleaning operation. This results in a thinner metal film layer, reducing the likelihood of film peeling. This improves the service life of the insulating edge and reduces the risk of edge arcing. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the steps of the present invention;

[0021] Figure 2 This is a schematic diagram of the S1-S2 steps of the present invention;

[0022] Figure 3 This is a schematic diagram of steps S3-S5 of the present invention. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0024] In the description of this invention, it should be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention 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, and therefore should not be construed as a limitation of the invention. Furthermore, in the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0025] Please see Figure 1This invention provides a technical solution: a metal plate design and cleaning method for cleaning etching chambers, comprising the following steps:

[0026] S1: Design a low sputtering yield metal thin film on the four sides of an aluminum plate. The metal thin film includes at least one of titanium, tungsten, and tantalum. The metal thin film has a significantly lower sputtering yield compared to aluminum material.

[0027] S2: Control the width and thickness of low-sputtering-yield films to make them suitable for material control and shielding requirements in subsequent sputtering processes;

[0028] S3: The aluminum plate is transferred to the substrate stage in the etching chamber, and the edge of the aluminum plate is pressed by the insulating plate, so that the insulating plate comes into contact with the low sputtering yield film and exposes part of the low sputtering yield film to the outside.

[0029] S4: By bombarding the surface of the aluminum plate with inert gas plasma, aluminum atoms and low sputtering yield metal atoms are sputtered from the surface and deposited onto the inner wall of the etching chamber and the surface of related components, thereby covering or encapsulating potential particles and reducing the risk of particle diffusion.

[0030] S5: By using low-sputtering-yield film to diffract onto the pressure plate bonding area, the film thickness is reduced, the risk of film peeling is lowered, and the service life of the insulating edge is extended.

[0031] The aluminum plate has a thickness of 0.5mm to 4.0mm and is rectangular in structure, with dimensions consistent with the substrate being produced and a side length greater than 200mm. The low-sputtering-yield metal film is made of titanium and has a thickness of 1μm. The low-sputtering-yield metal film is deposited using magnetron sputtering. The clamping width between the insulating plate and the aluminum plate is 1mm to 5mm. The insulating plate is made of quartz or ceramic. The inert gas is argon, and the plasma is argon plasma, used to sputter aluminum atoms and low-sputtering-yield metal atoms and deposit them onto the inner wall of the cavity and the surface of the components. As an inert gas, argon does not chemically react with aluminum or the metal film when excited to form plasma, ensuring that the entire sputtering process is purely physical and highly controllable. The metal atom deposition formed by argon plasma bombardment is uniform, suitable for surfaces of different cavity materials, and conducive to the formation of a stable coating layer. In addition, argon is abundant, low in cost, and highly safe, and is compatible with existing gas supply systems in industrial equipment without additional modifications, showing good prospects for widespread application.

[0032] Working principle: Low sputtering yield thin films, including Ti, W, Ta, etc., are designed on the four sides of the aluminum plate. The sputtering yield of the low sputtering yield thin film is about 30% to 40% of that of Al material. The width of the low sputtering yield thin film is about 10 mm to 40 mm, and the thickness is generally 0.5 μm to 10 μm.

[0033] When there is a risk of particles in the etching chamber, an aluminum plate is required. The designed aluminum plate is transferred to the top of the substrate stage, and an insulating plate presses the edge of the aluminum plate, that is, it contacts the low sputtering yield film on the edge of the aluminum plate. The pressing edge width is about 1mm to 5mm, and the exposed low sputtering yield film width is about 9mm to 40mm.

[0034] Ar plasma is used to bombard the surface of the aluminum plate, and Al atoms and low sputtering yield atoms are sputtered out and adhere to the inner wall of the cavity and the top of the components, which encapsulates or covers the particles and avoids the deterioration of particulate contamination.

[0035] Because the insulating edge contacts a low-sputtering-yield thin film, the metal film layer diffracted at its edge is thinner, making it less prone to problems such as film peeling. This improves the service life of the insulating edge.

[0036] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A metal plate design and cleaning method for cleaning etching chambers, characterized in that, Includes the following steps: S1: Design a low sputtering yield metal film on the four sides of an aluminum plate, the metal film including at least one of titanium, tungsten, and tantalum, the metal film having a significantly lower sputtering yield compared to aluminum material; S2: Control the width and thickness of the low-sputtering-yield film to make it suitable for the material control and shielding requirements in the subsequent sputtering process; S3: The aluminum plate is conveyed to the substrate stage in the etching chamber, and the edge of the aluminum plate is pressed by an insulating plate, so that the insulating plate comes into contact with the low sputtering yield film and a portion of the low sputtering yield film is exposed to the outside. S4: By bombarding the surface of the aluminum plate with inert gas plasma, aluminum atoms and low sputtering yield metal atoms are sputtered from the surface and deposited onto the inner wall of the etching chamber and the surface of related components, thereby covering or encapsulating potential particles and reducing the risk of particle diffusion. S5: The film thickness is reduced by the low sputtering yield film diffracted onto the pressure plate pressing area, which reduces the risk of film peeling and extends the service life of the insulating edge pressing.

2. The metal plate design and cleaning method for cleaning etching chambers according to claim 1, characterized in that: The thickness of the aluminum plate is 0.5 mm to 4.0 mm.

3. The metal plate design and cleaning method for cleaning etching chambers according to claim 1, characterized in that: The aluminum plate has a rectangular structure, with dimensions consistent with the produced substrate, and a side length greater than 200mm.

4. The metal plate design and cleaning method for cleaning etching chambers according to claim 1, characterized in that: The low-sputtering-yield metal film is made of titanium and has a thickness of 1 μm.

5. The metal plate design and cleaning method for cleaning etching chambers according to claim 1, characterized in that: The low-sputtering-yield metal thin film is deposited using a magnetron sputtering process.

6. The metal plate design and cleaning method for cleaning etching chambers according to claim 1, characterized in that: The pressing edge width between the insulating pressure plate and the aluminum plate is 1mm to 5mm.

7. The metal plate design and cleaning method for cleaning etching chambers according to claim 1, characterized in that: The insulating pressure plate is made of quartz or ceramic.

8. The metal plate design and cleaning method for cleaning etching chambers according to claim 1, characterized in that: The inert gas is argon, and the plasma is argon plasma, used to sputter aluminum atoms and low-sputter-yield metal atoms and deposit them onto the inner wall of the chamber and the surface of the components.

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