Method for balancing coating pressure intensity of N / P surface of process cavity and PVD (Physical Vapor Deposition) equipment

Abstract

The invention provides a method for balancing the N / P surface coating pressure intensity of a process cavity and PVD (Physical Vapor Deposition) equipment, and the method comprises the following steps: controlling each molecular pump of a P surface process cavity to run at a first preset pumping speed in the coating process of a material sheet; and part of molecular pumps in the N-face process cavity are controlled to operate at a second preset pumping speed, the second preset pumping speed is smaller than the first preset pumping speed, and the pressure intensity of the N-face process cavity is made to be equal to that of the N-face process cavity. According to the invention, the pumping speed of partial molecular pumps of the N-surface process cavity is reduced, so that the pressure balance between the N-surface process cavity and the P-surface process cavity is ensured, and the stability and reliability of the coating process are improved. Compared with a conventional method of increasing the gas flow of the N surface and lengthening the isolation cavity, the length of the isolation cavity is not reduced, the pressure intensity of the N / P surface is balanced, meanwhile, the gas consumption cost of the N surface is reduced, and the energy consumption and cost of equipment are effectively reduced.

Description

Technical Field

[0001] The present invention relates to the field of solar cell (HJT) PVD coating process, and in particular to a method for balancing the N / P surface coating pressure of a process chamber and a PVD device. Background Art

[0002] In the manufacturing process of HJT (heterojunction) cells, the coating process of TCO (transparent conductive oxide) thin film is one of the important links. The order of this process is to coat the P-side thin film first, and then coat the N-side thin film. The specific process is divided into two main stages: first, the P-side coating is completed by the lower cathode, and then the N-side coating is completed by the upper cathode through an isolation position.

[0003] In actual operation, if the same flow rate of gas is introduced into the NP-side cathode, the process pressure on the N-side will usually be lower than that on the P-side. This pressure difference will affect the uniformity and quality of the coating. The usual strategy is to adjust the total flow rate of the process gas on the N-side to make it greater than the flow rate on the P-side, thereby balancing the process pressure during the NP-side coating process. In addition, in order to avoid cross-gassing of the NP-side cathode during the coating process, it is usually necessary to increase the length of the isolation cavity and introduce additional molecular pumps. These improvement measures can effectively reduce gas cross-contamination, but also result in a significant increase in equipment costs. Summary of the invention

[0004] In order to solve the technical problem of high cost of balancing the process pressure of N / P surfaces in the above-mentioned prior art, the present invention provides a method for balancing the coating pressure of N / P surfaces of a process chamber and a PVD device.

[0005] The technical solution adopted by the present invention is:

[0006] The present invention proposes a method for balancing the N / P surface coating pressure of a process chamber, wherein a material sheet is sequentially coated through a P surface process chamber, an isolation chamber, and an N surface process chamber;

[0007] During the coating process of the material sheet, each molecular pump of the P-side process chamber is controlled to operate at a first preset pumping speed so that the pressure of the P-side process chamber is maintained at a preset pressure;

[0008] Control some molecular pumps in the N-side process chamber to run at a second preset pumping speed so that the pressure of the N-side process chamber is maintained at the preset pressure, or the deviation value obtained by subtracting the preset pressure from the pressure of the N-side process chamber is within a preset deviation range; and the second preset pumping speed is less than the first preset pumping speed.

[0009] First embodiment: a plurality of molecular pumps arranged near the isolation chamber in the N-side process chamber operate at a first preset pumping speed, and the remaining molecular pumps reduce their pumping speeds and operate at a second preset pumping speed.

[0010] Second embodiment: The multiple molecular pumps in the N-side process chamber are divided into a first molecular pump group, a second molecular pump group, and a third molecular pump group according to the distance from the isolation chamber from near to far; wherein the first molecular pump group operates at a first preset pumping speed, the second molecular pump group operates at a second preset pumping speed, and the third molecular pump group operates at a third preset pumping speed, and the third preset pumping speed is less than the second preset pumping speed.

[0011] The third embodiment: the number of molecular pumps in the N-side process chamber is the same as the number of molecular pumps in the P-side process chamber, and the pumping speeds of the two molecular pumps near the end of the N-side process chamber are reduced to the second preset pumping speed, and the pumping speeds of the other molecular pumps are operated at the first preset pumping speed.

[0012] Specifically, each molecular pump of the isolation chamber is controlled to operate at a first preset pumping speed.

[0013] Preferably, the first preset pumping speed is 100%.

[0014] Preferably, the second preset pumping speed is set in a range of 50%-80%.

[0015] The present invention further provides a PVD device, which uses the above-mentioned method of balancing the N / P surface coating pressure of the process chamber to balance the coating pressure of the P-side process chamber and the N-side process chamber.

[0016] Specifically, the P-side process chamber is sequentially provided with 6 molecular pumps numbered 1 to 6 in cathode position order, the isolation process is sequentially provided with 2 molecular pumps numbered 7 to 8, and the N-side process chamber is sequentially provided with 11 molecular pumps numbered 9 to 19 in cathode position order.

[0017] Specifically, the P-side process chamber is sequentially provided with 6 molecular pumps numbered 1 to 6 in cathode position order, the isolation process is sequentially provided with 2 molecular pumps numbered 7 to 8, and the N-side process chamber is sequentially provided with 6 molecular pumps numbered 9 to 14 in cathode position order.

[0018] Compared with the prior art, the present invention reduces the pumping speed of some molecular pumps in the N-side process chamber to ensure the pressure balance between the N-side process chamber and the P-side process chamber, thereby improving the stability and reliability of the coating process. Compared with the conventional method of increasing the gas flow rate on the N-side and lengthening the isolation chamber, the length of the isolation chamber is not reduced and the pressure of the N / P surfaces is balanced, while the gas consumption cost of the N-side is reduced, effectively reducing the energy consumption and maintenance cost of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0020] Figure 1 It is a structural diagram of the equipment for balancing the process pressure of NP surface coating in the prior art;

[0021] Figure 2 A structural diagram of a device for balancing process pressure during film coating of a PVD device provided in the first embodiment of the present invention;

[0022] Figure 3 A structural diagram of a device for balancing process pressure during film coating of a PVD device provided in the second embodiment of the present invention;

[0023] Figure 4 This is a structural diagram of an apparatus for balancing process pressure during film coating of a PVD apparatus provided in the third embodiment of the present invention. DETAILED DESCRIPTION

[0024] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0025] The principle and structure of the present invention are described in detail below with reference to the accompanying drawings and embodiments.

[0026] like Figure 1 As shown in the figure, this chart shows the equipment configuration of the TCO thin film coating process in the HJT battery manufacturing process in the prior art. Among them, the C41 coating chamber is a P-side process chamber, including positions 1 to 4; the C42 coating chamber is an isolation chamber, including positions 5 to 8; and the C43 coating chamber is an N-side process chamber, including positions 9 to 11. The pumping speeds of the various molecular pumps in the existing process chambers are the same, so the total flow rate of the N-side process gas is generally adjusted to be greater than the flow rate of the P-side, thereby balancing the process pressure during the NP-side coating process, or increasing the length of the isolation chamber and introducing additional molecular pumps, which is costly.

[0027] In this regard, the present invention proposes a method for balancing the N / P surface coating pressure of the process chamber, wherein the material is sequentially coated through the P surface process chamber, the isolation chamber and the N surface process chamber; wherein the balancing method comprises:

[0028] During the coating process of the material sheet, each molecular pump of the P-side process chamber is controlled to operate at a first preset pumping speed so that the pressure of the P-side process chamber is maintained at a preset pressure;

[0029] Control some molecular pumps in the N-side process chamber to run at a second preset pumping speed, so that the pressure of the N-side process chamber is maintained at a preset pressure, that is, the same as the pressure of the P-piece process chamber, or the deviation value obtained by subtracting the preset pressure from the pressure of the N-side process chamber is within a preset deviation range; and the second preset pumping speed is less than the first preset pumping speed.

[0030] By reducing the pumping speed of the molecular pump of part of the N-side process chamber to the second preset pumping speed, the extraction rate of the molecular pump on the gas in the N-side process chamber is reduced, the process gas content in the chamber is increased, thereby increasing the pressure of the N-side process chamber, so that the pressure of the N-side process chamber is maintained within a preset value or a control deviation range.

[0031] By setting the second preset pumping speed lower than the first preset pumping speed, the pressure balance between the two chambers is ensured, thereby improving the stability and reliability of the coating process. Compared with the conventional method of increasing the gas flow on the N side and lengthening the isolation chamber, the length of the isolation chamber is not reduced and the pressure on the N / P sides is balanced, while the gas consumption cost on the N side is reduced, effectively reducing the energy consumption and maintenance cost of the equipment.

[0032] There are multiple embodiments for setting the pumping speed of the molecular pump of the specific N-side process chamber, and as long as it is to make the pressure of the N-side process chamber equal to the preset pressure, or to make the deviation of the pressure of the N-side process chamber relative to the preset pressure less than the preset deviation value; and the second preset pumping speed is less than the first preset pumping speed.

[0033] In a specific embodiment, during the coating process of the wafer, each molecular pump of the isolation chamber is controlled to run at a first preset pumping speed, which is the same as the pumping speed of the molecular pumps of the P-side process chamber and the N-side process chamber close to the isolation chamber to avoid leakage.

[0034] In a specific embodiment, the material sheet is specifically a battery sheet.

[0035] In a specific embodiment, the preset pressure may be about 0.6 Pa.

[0036] The preset deviation range can be set to -0.001Pa to 0.001Pa. When the pressure of the P-side process chamber is 0.6Pa and the pressure of the N-side process chamber is 0.599Pa, the deviation value is 0.001, which is within this range. In addition, the preset deviation range can also be set to other reasonable ranges according to the process accuracy requirements, which are all within the protection scope of the present invention.

[0037] In a specific embodiment, the preset pressure may be about 0.6 Pa.

[0038] In a specific embodiment, the first preset pumping speed is preferably 100%, the second preset pumping speed, and the preferred range of the second preset pumping speed is 50% to 80%. It should be noted that the molecular pump pumping speed range is 0% to 100%, 0% is shutdown, and 100% is full speed.

[0039] In a specific embodiment, after the battery cell is coated, it is transferred from the process chamber to the discharge buffer chamber.

[0040] First embodiment:

[0041] The multiple molecular pumps arranged near the isolation chamber in the N-side process chamber run at the first preset pumping speed, and the remaining molecular pumps reduce the pumping speed and run at the second preset pumping speed. By running the molecular pumps near the isolation chamber at the first preset pumping speed, the gas near the isolation chamber area can be quickly extracted to prevent the gas in the isolation chamber from entering the N-side process chamber, thereby ensuring the gas isolation effect between the isolation chamber and the P-side and N-side. The remaining molecular pumps in the N-side process chamber are reduced to the second preset pumping speed to increase the overall gas content of the N-side process chamber by slowing down the gas extraction rate in these areas, thereby effectively increasing the overall pressure of the N-side process chamber and balancing the pressure difference between the N / P surfaces.

[0042] Further, such as Figure 2 As shown in the figure, during the PVD coating process, the preset pressure of the coating process is 0.6Pa, and the cell (210x105 mm) cell enters the C41 process chamber for P-side coating. The molecular pump of the P-side process chamber runs at the first preset pumping speed, that is, 100% full speed; the molecular pump close to the isolation chamber (such as the molecular pump adjacent to position 7 or position 8) continues to run at the first preset pumping speed, which is used to quickly extract the gas near the isolation chamber, maintain the low pressure of the isolation chamber and reduce gas cross-flow; the molecular pumps far away from the isolation chamber or located in other areas of the N-side cavity (such as molecular pumps 13 to 19) are reduced to the second preset pumping speed of 50% to 80%, so that the overall gas content of the N-side process chamber is moderately increased, thereby increasing the pressure of the N-side. This can stably achieve a pressure matching the P-side without changing the length of the isolation chamber.

[0043] Second embodiment:

[0044] In the N-side process chamber, according to the distance between the molecular pump and the isolation chamber from near to far, it is divided into the first molecular pump group, the second molecular pump group and the third molecular pump group. The first molecular pump group runs at the first preset pumping speed, which is used to quickly extract the gas near the isolation chamber, maintain the low pressure of the isolation chamber and avoid gas cross-flow; the second molecular pump group runs at the second preset pumping speed, which is used to further control the gas content in the central area of ​​the N-side process chamber, so that the pressure is consistent with the P-side or maintained within the allowable deviation range; the third molecular pump group runs at the third preset pumping speed, and increases the retention of gas in the chamber by reducing the pumping rate, so that the pressure of the chamber away from the isolation chamber area is further increased or maintained at the target value. The third preset pumping speed is less than the second preset pumping speed, which helps to moderately increase the concentration of process gas at the farther end of the N-side cavity, thereby achieving a refined balance of the overall pressure of the N-side.

[0045] Further, such as Figure 3 As shown, during the PVD coating process, the preset pressure of the coating process is 0.6 Pa, and the cell (210x105 mm) cell enters the C41 process chamber for P-side coating, and the molecular pump of the P-side process chamber runs at the first preset pumping speed, that is, 100% of the full speed;

[0046] The first molecular pump group is specifically molecular pumps No. 9 to No. 12, which operate at a first preset pumping speed, i.e., 100% of the full speed; the second molecular pump group is specifically molecular pumps No. 13 and No. 14, which have the same pumping speed and operate at a second preset pumping speed, which is specifically selected between 50% and 80%; the third molecular pump group is specifically molecular pumps No. 15 to No. 19, which have the same pumping speed and operate at a third preset pumping speed, which is specifically selected between 50% and 80%, and the third preset pumping speed is less than the second preset pumping speed.

[0047] Third embodiment:

[0048] In this embodiment, the number of molecular pumps in the N-side process chamber is set to be the same as the number of molecular pumps in the P-side process chamber, that is, some cathode positions and molecular pumps in the N-side process chamber are reduced. The two molecular pumps near the end of the N-side process chamber reduce the pumping speed to the second preset pumping speed; reducing the pumping intensity in the end area.

[0049] Specific as Figure 4 As shown, the PVD equipment machine reduces the speed of the N-side molecular pump No. 13 and No. 14 molecular pumps to 50% to 80%, and at the same time removes cathode positions nine to eleven (copper target seed layer coating chamber), thereby achieving the goal of improving production efficiency.

[0050] The present invention also proposes a PVD device, which uses the above-mentioned method of balancing the N / P surface coating pressure of the process chamber to balance the coating pressure of the P-surface process chamber and the N-surface process chamber.

[0051] In the first and second embodiments, Figure 2 ,3 As shown, the P-side process chamber is configured with 6 molecular pumps in the order of cathode position, numbered from 1 to 6; the isolation process chamber is configured with 2 molecular pumps, numbered 7 and 8; the N-side process chamber is configured with 11 molecular pumps in the order of cathode position, numbered from 9 to 19.

[0052] In the third embodiment, if Figure 4 As shown, the P-side process chamber is provided with 6 molecular pumps numbered 1 to 6 in sequence according to the cathode position, and each molecular pump operates at a first preset pumping speed according to the process requirements to maintain the gas content and pressure stability in the P-side process chamber;

[0053] The isolation process chamber is sequentially provided with two molecular pumps numbered 7 to 8, which maintain the first preset pumping speed at a high pumping speed, thereby effectively isolating the process gases on the P surface and the N surface;

[0054] The N-side process chamber is provided with six molecular pumps numbered 9 to 14 in the order of cathode position, among which the molecular pumps numbered 9 to 12 close to the isolation chamber operate at the first preset pumping speed to ensure the low pressure stability of the isolation chamber and reduce the interference of the P-side gas. The remaining molecular pumps (numbered 13 to 14) operate at the second preset pumping speed, and the gas content of the N-side process chamber is increased by reducing the pumping speed, thereby increasing the overall pressure of the N-side process chamber.

[0055] Compared with the traditional method, the PVD equipment uses the molecular pump configuration and pumping speed differentiation operation strategy to optimize the molecular pump distribution and pumping speed adjustment, while ensuring the pressure balance of the N / P surface coating, and significantly improve the energy efficiency and process reliability of the equipment operation. This increases the service life of the molecular pump of the PVD equipment and achieves the technical effect of reducing the cost of PVD equipment, protection and maintenance.

[0056] It should be noted that the terms used above are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0057] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

Claims

1. A method for balancing the N / P surface coating pressure of a process chamber, wherein a material is sequentially coated through a P surface process chamber, an isolation chamber, and an N surface process chamber; characterized in that: During the coating process of the material sheet, each molecular pump of the P-side process chamber is controlled to operate at a first preset pumping speed so that the pressure of the P-side process chamber is maintained at a preset pressure; Controlling some molecular pumps in the N-side process chamber to operate at a second preset pumping speed, where the second preset pumping speed is less than the first preset pumping speed, so that the pressure of the N-side process chamber is maintained at a preset pressure, or a deviation value obtained by subtracting the preset pressure from the pressure of the N-side process chamber is within a preset deviation range.

2. The method for balancing the N / P surface coating pressure of a process chamber as claimed in claim 1, characterized in that: A plurality of molecular pumps arranged near the isolation chamber in the N-side process chamber operate at a first preset pumping speed, and the remaining molecular pumps reduce their pumping speeds and operate at a second preset pumping speed.

3. The method for balancing the N / P surface coating pressure of a process chamber as claimed in claim 1, characterized in that: The multiple molecular pumps in the N-side process chamber are divided into a first molecular pump group, a second molecular pump group, and a third molecular pump group according to the distance from the isolation chamber from near to far; The first molecular pump group operates at a first preset pumping speed, the second molecular pump group operates at a second preset pumping speed, and the third molecular pump group operates at a third preset pumping speed, and the third preset pumping speed is less than the second preset pumping speed.

4. The method for balancing the N / P surface coating pressure of a process chamber as claimed in claim 1, characterized in that: The number of molecular pumps in the N-side process chamber is the same as the number of molecular pumps in the P-side process chamber, and the pumping speeds of the two molecular pumps near the end of the N-side process chamber are reduced to the second preset pumping speed, and the pumping speeds of the other molecular pumps are operated at the first preset pumping speed.

5. The method for balancing the N / P surface coating pressure of a process chamber as claimed in claim 1, characterized in that: Each molecular pump of the isolation chamber is controlled to operate at a first preset pumping speed.

6. The method for balancing the N / P surface coating pressure of a process chamber according to any one of claims 1 to 5, characterized in that: The first preset pumping speed is 100%.

7. The method for balancing the N / P surface coating pressure of a process chamber according to any one of claims 1 to 5, characterized in that: The setting range of the second preset pumping speed is 50%-80%.

8. A PVD device, characterized in that: The method for balancing the N / P surface coating pressure of a process chamber as described in any one of claims 1 to 7 is used to balance the coating pressure of a P-surface process chamber and an N-surface process chamber.

9. The PVD device according to claim 8, characterized in that The P-side process chamber is provided with 6 molecular pumps numbered 1 to 6 in sequence according to the cathode position, the isolation process is provided with 2 molecular pumps numbered 7 to 8 in sequence, and the N-side process chamber is provided with 11 molecular pumps numbered 9 to 19 in sequence according to the cathode position.

10. The PVD device according to claim 8, characterized in that The P-side process chamber is provided with 6 molecular pumps numbered 1 to 6 in sequence according to the cathode position, the isolation process is provided with 2 molecular pumps numbered 7 to 8 in sequence, and the N-side process chamber is provided with 6 molecular pumps numbered 9 to 14 in sequence according to the cathode position.

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