Electrostatic force control device and thin film deposition apparatus

Abstract

The utility model discloses a kind of electrostatic force control device and thin film deposition equipment, the device includes: reaction chamber, heating tray and the spray tray located in the heating tray above are arranged in the reaction chamber, and the heating tray can place wafer;Gas purging unit, with the spray tray intercommunication, for into the spray tray into cleaning gas;Ion wind generating unit, with the gas purging unit is connected, for generating ion wind with charge.The utility model in purge process into charged ion wind, not only can remove particle and other particulate matter, but also can remove the electrostatic force inside reaction chamber and wafer surface by charge neutralization, avoid the support pin of heating tray when lifting support wafer, electrostatic force on wafer surface produces influence, wafer surface electrostatic force can be reduced simultaneously, to avoid particulate matter adsorbed on wafer surface, thereby improve thin film deposition production effect.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor technology, and in particular to an electrostatic force control device and a thin film deposition equipment. Background Technology

[0002] In thin film deposition processes, surface flatness defects on the back side of the wafer (such as micro-bumps or depressions) can lead to defocusing during exposure, thereby reducing chip yield. These defects are caused by factors including uneven film stress due to deposition temperature fluctuations, localized thickness deviations due to impurity adhesion, and electrostatic adsorption effects accumulated during the process. Electrostatic forces exacerbate defects through mechanisms such as charged particles adsorbing onto the wafer surface to form microscopic irregularities, or exposure dose shifts caused by electric field interference during subsequent photolithography. Traditional solutions, such as replacing with low-static heaters or extending the inert gas purging time, can alleviate the problem but significantly increase process complexity and throughput. For example, while extending the purging time effectively neutralizes the charge, it reduces equipment turnaround efficiency; replacing the heating pad with one with lower electrostatic force may introduce new thermal inhomogeneities, creating a chain reaction within the process window. Therefore, how to reduce electrostatic forces inside the reaction chamber and on the wafer surface to improve thin film deposition production efficiency is a problem that needs to be solved by those skilled in the art. Utility Model Content

[0003] This invention provides an electrostatic force control device and a thin film deposition equipment, which aim to reduce the electrostatic force inside the reaction chamber and on the wafer surface.

[0004] This utility model embodiment provides an electrostatic force control device, including: A reaction chamber is provided with a heating plate and a spray plate located above the heating plate, and the heating plate can hold a wafer; A gas purging unit, connected to the spray plate, is used to introduce purging gas into the spray plate; An ion wind generating unit, connected to the gas purging unit, is used to generate an ion wind with an electrical charge.

[0005] Furthermore, the ion wind generating unit includes a pulsed DC ion wind fan.

[0006] Furthermore, the ion wind generating unit also includes a high-voltage generator, which is used to control the output frequency of the ion wind.

[0007] Furthermore, the ion wind carries a positive charge.

[0008] Furthermore, the gas introduced into the ion wind generating unit is an ionizable gas.

[0009] Furthermore, the ionizable gas includes any one of nitrogen, helium, and argon.

[0010] Furthermore, it also includes a gas distribution unit, which is provided with an air inlet and an air outlet. The air inlet is connected to the gas purging unit and the ion wind generating unit, respectively, and the air outlet is connected to the spray plate.

[0011] Furthermore, the gas distribution unit is a gas distribution aluminum block.

[0012] Furthermore, multiple ion wind generating units and gas separation units are provided.

[0013] This utility model embodiment also provides a thin film deposition apparatus, including the electrostatic control device as described in any of the preceding embodiments.

[0014] This invention provides an electrostatic force control device and a thin film deposition apparatus. The device includes: a reaction chamber, in which a heating plate and a spray plate located above the heating plate are disposed, and the heating plate can hold a wafer; a gas purging unit, connected to the spray plate, for introducing purging gas into the spray plate; and an ion wind generating unit, connected to the gas purging unit, for generating charged ion wind. This invention introduces charged ion wind during the purging process, which not only removes particulate matter such as particles, but also neutralizes the electrostatic forces inside the reaction chamber and on the wafer surface through charge neutralization. This prevents the electrostatic forces on the wafer surface from affecting the support pins of the heating plate when they are raised to support the wafer, and also reduces the electrostatic forces on the wafer surface to prevent particulate matter from adsorbing onto the wafer surface, thereby improving the thin film deposition production effect. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 A flowchart illustrating an electrostatic force control device provided in an embodiment of this utility model; Figure 2 A schematic diagram of the principle of an electrostatic force control device provided in an embodiment of this utility model; Figure 3 A comparative schematic diagram of an electrostatic force control device provided for an embodiment of this utility model; Figure 4 A neutralization schematic diagram of an electrostatic force control device provided in this embodiment of the present invention. Figure 5 This is a flowchart illustrating an electrostatic force control device provided in an embodiment of the present invention.

[0017] Markings in the image: 10. Reaction chamber; 20. Heating plate; 21. Wafer; 30. Spray plate; 40. Gas purging unit; 50. Ion wind generation unit; 60. Gas distribution unit. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0019] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0020] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0021] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0022] Please see below. Figure 1 and Figure 2 This utility model provides an electrostatic force control device, comprising: The reaction chamber 10 is provided with a heating plate 20 and a spray plate 30 located above the heating plate 20, and the heating plate 20 can hold a wafer 21. The gas purging unit 40 is connected to the spray plate 30 and is used to introduce purging gas into the spray plate 30. The ion wind generating unit 50 is connected to the gas purging unit 40 and is used to generate charged ion wind.

[0023] In this embodiment, the electrostatic control device includes a reaction chamber 10, a spray plate 30, a heating plate 20, a gas purging unit 40, and an ion wind generating unit 50. The spray plate 30 is located above the heating plate 20 and can uniformly spray gas onto the surface of the wafer 21, achieving effective processing of the wafer 21. The heating plate 20 not only holds the wafer 21 but also provides a suitable temperature environment for it to meet the process requirements of thin film deposition. The gas purging unit 40 is connected to the spray plate 30; by introducing purging gas into the spray plate 30, impurities and particulate matter in the reaction chamber 10 can be removed in a timely manner, ensuring a clean reaction environment. The ion wind generation unit 50 is connected to the gas purging unit 40 and can generate charged ion wind. During the purging process, this ion wind not only removes particulate matter such as particles but also neutralizes the electrostatic forces inside the reaction chamber 10 and on the surface of the wafer 21 through charge neutralization. This effectively prevents the electrostatic forces on the wafer 21 surface from having an adverse effect when the support pins of the heating plate 20 are raised to support the wafer 21. Simultaneously, it reduces the electrostatic forces on the wafer 21 surface, preventing particulate matter from adsorbing onto the wafer 21 surface, thereby improving the thin film deposition production effect. In practical applications, the parameters of each unit can be flexibly adjusted according to specific process requirements to achieve the best electrostatic force control effect.

[0024] Combination Figure 3 and Figure 4 The wafer 21 is attracted to the heating plate 20 by electrostatic force. The charge is slowly discharged through the heating plate 20. If the electrostatic force is not completely released, the support pin of the heating plate 20 will rise, which will cause abnormality on the back side of the wafer 21. However, after positive ions are introduced during the purging operation, the positive ions neutralize the negative charge on the wafer 21 and eliminate the electrostatic force. In this way, the wafer 21 will not be subjected to additional electrostatic force when the support pin rises, thereby avoiding the defocus problem.

[0025] In one embodiment, the ion wind generating unit 50 includes a pulsed DC ion wind fan.

[0026] In this embodiment, a pulsed DC ion fan is used to generate ion wind. This type of ion fan ionizes the gas using a pulsed DC electric field, thereby producing charged ion wind. The pulsed DC method allows for more stable and controllable ion wind generation, enabling the adjustment of the ion wind intensity and frequency according to actual process requirements to achieve better electrostatic neutralization. Furthermore, the pulsed DC ion fan also boasts advantages such as small size, high efficiency, and long lifespan, making it highly suitable for use in thin film deposition equipment. In practical applications, a suitable pulsed DC ion fan model can be selected based on the size of the reaction chamber 10 and process requirements to ensure effective ion wind coverage and neutralization.

[0027] Furthermore, the ion wind generating unit 50 also includes a high-voltage generator, which is used to control the output frequency of the ion wind.

[0028] This embodiment uses a high-voltage generator to precisely control the output frequency of the ion wind. The high-voltage generator produces a stable high-voltage electric field, providing the necessary energy for the generation of the ion wind. By adjusting the output voltage and frequency of the high-voltage generator, precise control of the ion wind output frequency can be achieved, thereby meeting the diverse needs for electrostatic neutralization at different process stages. For example, in the early stages of thin film deposition, a higher frequency ion wind may be needed to quickly neutralize the static electricity on the wafer 21 surface; while in the later stages of deposition, the ion wind frequency can be appropriately reduced to avoid interfering with the deposition process. This flexible control method allows the electrostatic control device to better adapt to various complex thin film deposition process requirements.

[0029] In a specific embodiment, the ion wind carries a positive charge.

[0030] In this embodiment, the ion wind is chosen to be positively charged based on an in-depth analysis of the electrostatic force distribution characteristics during thin film deposition. During deposition, negative charges often accumulate on the surface of wafer 21, leading to electrostatic adsorption of particles and affecting deposition quality. By generating a positively charged ion wind, the negative charges on the wafer 21 surface can be effectively neutralized, thereby eliminating the adverse effects of electrostatic forces on the deposition process. Simultaneously, the positively charged ion wind can also interact with other charged particles within the reaction chamber 10, further improving the reaction environment and enhancing the uniformity and stability of the thin film deposition.

[0031] In addition, the gas introduced into the ion wind generating unit 50 is an ionizable gas.

[0032] In this embodiment, ionizable gas is used as the raw material for the ion wind generation unit 50 because ionizable gas is more easily ionized under a high-voltage electric field, thereby generating charged ion wind. This not only improves the generation efficiency of ion wind but also makes the ion wind more controllable and stable. At the same time, ionizable gas usually has high chemical stability and will not cause corrosion or contamination to other components and wafer 21 in the reaction chamber 10, ensuring the purity and reliability of the thin film deposition process.

[0033] Specifically, the ionizable gas includes any one of nitrogen, helium, and argon.

[0034] This embodiment uses nitrogen, helium, and argon as ionizable gases. These gases are common inert or rare gases, characterized by their chemical stability and resistance to reaction with other substances. Using these gases as the raw material for the ion wind during thin film deposition avoids the introduction of impurities or contaminants, ensuring the purity and quality of the deposited film. Simultaneously, these gases possess excellent ionization properties, rapidly generating an ion wind under a high-voltage electric field, meeting the requirements for electrostatic control. In practical applications, the appropriate type of ionizable gas can be selected based on specific process requirements and cost considerations.

[0035] In one embodiment, the electrostatic force control device further includes a gas distribution unit 60, which is provided with an air inlet and an air outlet. The air inlet is connected to the gas purging unit 40 and the ion wind generating unit 50, respectively, and the air outlet is connected to the spray plate 30.

[0036] This embodiment achieves precise control of gas flow direction by setting up a gas distribution unit 60. Specifically, the gas inlet of the gas distribution unit 60 is connected to the gas purging unit 40 and the ion wind generating unit 50, enabling it to simultaneously receive gas from these two units and mix or distribute it within the unit. The gas outlet is connected to the spray plate 30, ensuring that the mixed gas can be uniformly and stably input into the spray plate 30. This design not only improves gas utilization efficiency but also allows the electrostatic control device to more flexibly respond to different process requirements. For example, by adjusting the inlet ratio of the gas distribution unit 60, the mixing ratio of ion wind and purging gas can be changed, thereby achieving fine adjustment of the electrostatic neutralization effect. At the same time, the structural design of the gas distribution unit 60 also fully considers the gas flow and pressure distribution, ensuring the stability and reliability of the gas during transmission. In practical applications, the materials and manufacturing processes of the gas distribution unit 60 also need to undergo strict selection and control to ensure that it can withstand the impact and corrosion of high-pressure gas and guarantee long-term stable operation.

[0037] Specifically, the gas distribution unit 60 is a gas distribution aluminum block.

[0038] In this embodiment, an aluminum gas distribution block is used as the gas distribution unit 60 because aluminum has good thermal conductivity, corrosion resistance, and processing performance. The interior of the aluminum gas distribution block can be designed with complex flow channel structures to meet the requirements for precise gas distribution and regulation. Simultaneously, the surface of the aluminum block can be smoothed to reduce resistance and turbulence during gas flow, improving the uniformity and stability of gas distribution. Furthermore, the aluminum gas distribution block has high structural strength and durability, capable of withstanding the high temperature and high pressure environment within the reaction chamber 10, ensuring the long-term stable operation of the electrostatic control device. In practical applications, suitable dimensions and flow channel structures for the aluminum gas distribution block can be customized according to specific process requirements and equipment specifications.

[0039] Furthermore, multiple ion wind generating units 50 and gas-distributing aluminum blocks can be set according to actual needs. For example, in practical applications, if the reaction chamber 10 is large or the process requires more precise and strict control of electrostatic forces, setting multiple ion wind generating units 50 and gas-distributing aluminum blocks becomes essential. Multiple ion wind generating units 50 can work simultaneously, generating more charged ion winds, thereby enhancing the neutralization ability of electrostatic forces inside the reaction chamber 10 and on the surface of the wafer 21. For example, in large-scale thin film deposition equipment, a single ion wind generating unit 50 may not be able to fully cover the entire reaction area, resulting in insufficient neutralization of electrostatic forces in some areas, affecting the quality of thin film deposition. Multiple ion wind generating units 50 generate ion winds from different positions, which can be more evenly distributed to all corners of the reaction chamber 10, effectively eliminating electrostatic forces.

[0040] By setting up multiple gas distribution aluminum blocks, gas can be distributed and adjusted more flexibly. Different process stages may require different mixing ratios of ionizing air and purge gas. Multiple gas distribution aluminum blocks can independently and precisely control the gas in different areas or process stages. For example, in the early stages of thin film deposition, some areas may require a higher proportion of ionizing air to quickly neutralize electrostatic forces, while other areas may have a greater need for purge gas. In this case, multiple gas distribution aluminum blocks can distribute the gas according to different requirements, meeting diverse process needs. Moreover, the cooperation of multiple gas distribution aluminum blocks can also improve the redundancy and reliability of the entire gas distribution system. When one gas distribution aluminum block fails, the others can still ensure basic gas distribution, ensuring the normal operation of the electrostatic control device and reducing production interruptions and losses caused by equipment failure.

[0041] like Figure 5 As shown, this utility model embodiment also provides a method for using an electrostatic force control device, applied to the electrostatic force control device as described in any of the above claims, the method comprising: steps S101 to S103.

[0042] Step S101: Generate charged ion wind using ion wind generation unit 50; Step S102: The ion wind and the cleaning gas introduced by the gas purging unit 40 are mixed and then input into the spray plate 30; Step S103: Neutralize and control the electrostatic force inside the reaction chamber 10 and on the surface of the wafer 21 by inputting gas into the spray plate 30.

[0043] In this embodiment, when performing electrostatic force control based on an electrostatic force control device, an ion wind generating unit 50 is first used to generate a charged ion wind. This process utilizes a specific structure within the ion wind generating unit 50, such as a pulsed DC ion fan combined with a high-voltage generator, to ionize the ionizable gas, thereby generating a charged ion wind. This positively charged ion wind effectively neutralizes the negative charge accumulated on the surface of wafer 21 during thin film deposition. Next, the generated ion wind is mixed with the cleaning gas introduced by the gas purging unit 40. If a gas distribution unit 60 is provided, it can precisely control the gas flow direction, allowing the ion wind and cleaning gas to mix or distribute within the gas distribution unit 60, ensuring that the mixing ratio meets different process requirements. Finally, the fused gas is input into the spray plate 30, which sprays the gas evenly inside the reaction chamber 10 and on the surface of the wafer 21. Through the charge neutralization effect of the ion wind in the gas and the cleaning effect of the cleaning gas, the electrostatic force inside the reaction chamber 10 and on the surface of the wafer 21 is neutralized and controlled. This avoids the electrostatic force on the surface of the wafer 21 from having an adverse effect when the support pin of the heating plate 20 is raised to support the wafer 21. At the same time, it reduces the electrostatic force on the surface of the wafer 21, prevents particulate matter from adsorbing on the surface of the wafer 21, and thus improves the thin film deposition production effect.

[0044] In a specific embodiment, the required positively charged ion wind can be generated by adjusting the pulse period. During the purging process, the ion wind flows into the chamber through the spray plate 30 via the gas distribution aluminum block (the amount of ions entering the chamber can be adjusted by regulating the output frequency and airflow of the ion wind high-voltage generator, thereby optimizing the electrostatic elimination effect). The ions entering the chamber utilize the principle of positive and negative charge neutralization to quickly remove static electricity from the surface of wafer 21. For example, a shorter pulse period can generate a more concentrated and powerful positively charged ion wind, suitable for situations where static electricity accumulation on the surface of wafer 21 is severe, and can quickly neutralize a large amount of negative charge, allowing the surface of wafer 21 to quickly return to a state of electrostatic equilibrium. When the static electricity accumulation on the surface of wafer 21 is relatively small, the pulse period can be appropriately extended to achieve effective neutralization of static electricity while avoiding unnecessary interference to the surface of wafer 21 caused by an excessively strong ion wind. At the same time, the distribution and adjustment of the ion wind by the gas distribution aluminum block can ensure that the ion wind flows evenly into all areas inside the chamber. Furthermore, the spray disks 30 at different locations can adjust the inflow rate and velocity of the ion air according to actual process requirements, ensuring that the entire surface of the wafer 21 receives uniform and thorough electrostatic neutralization treatment. This precise control method can greatly improve the effectiveness and stability of electrostatic control, thereby effectively improving the quality and yield of thin film deposition and providing a strong guarantee for the stable operation and efficient production of the thin film deposition process.

[0045] This utility model embodiment also provides a thin film deposition apparatus, including the electrostatic control device as described in any of the preceding embodiments.

[0046] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to in the method section. It should be noted that those skilled in the art can make various improvements and modifications to this application without departing from the principles of this application, and these improvements and modifications also fall within the protection scope of the claims of this application.

[0047] It should also be noted that, in this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. An electrostatic force control device, characterized in that, include: A reaction chamber is provided with a heating plate and a spray plate located above the heating plate, and the heating plate can hold a wafer; A gas purging unit, connected to the spray plate, is used to introduce purging gas into the spray plate; An ion wind generating unit, connected to the gas purging unit, is used to generate an ion wind with an electrical charge.

2. The electrostatic force control device according to claim 1, characterized in that, The ion wind generating unit includes a pulsed DC ion wind fan.

3. The electrostatic force control device according to claim 1, characterized in that, The ion wind generating unit also includes a high-voltage generator, which is used to control the output frequency of the ion wind.

4. The electrostatic force control device according to claim 1, characterized in that, The ion wind carries a positive charge.

5. The electrostatic force control device according to claim 1, characterized in that, The gas introduced into the ion wind generating unit is an ionizable gas.

6. The electrostatic force control device according to claim 5, characterized in that, The ionizable gas includes any one of nitrogen, helium, and argon.

7. The electrostatic force control device according to claim 1, characterized in that, It also includes a gas distribution unit, which is provided with an air inlet and an air outlet. The air inlet is connected to the gas purging unit (40) and the ion wind generating unit, respectively, and the air outlet is connected to the spray plate.

8. The electrostatic force control device according to claim 7, characterized in that, The gas distribution unit is a gas distribution aluminum block.

9. The electrostatic force control device according to claim 7, characterized in that, Multiple ion wind generating units and gas separation units are provided.

10. A thin film deposition apparatus, characterized in that, Includes the electrostatic force control device as described in any one of claims 1-8.

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