Method and system for monitoring coating thickness of vacuum support plate and support plate

Abstract

The invention discloses a method and a system for monitoring the coating thickness of a vacuum support plate and the support plate. The method comprises the steps that before film coating is started, a weight measuring piece is fixed to a fixing groove of a carrier plate, after the weight measuring piece is fixed, the target surface of the weight measuring piece is flush with the film coating surface of the carrier plate, and the target surface is matched with an opening, in the film coating surface, of the fixing groove; after film coating is stopped, the weight measuring piece is taken down from the carrier plate, and the weight of the weight measuring piece is measured; and determining the current coating thickness according to the weight measurement result of the weight measuring piece. Therefore, the invention provides a film thickness monitoring technology which can improve the production efficiency, reduce the cost and is relatively high in detection precision.

Description

Technical Field

[0001] The present application relates to the field of film coating, and in particular to a method and system for monitoring the coating thickness of a vacuum carrier, and a carrier. Background Art

[0002] In some coating processes, the coating thickness needs to be monitored. Taking heterojunction solar cells as an example, with the rapid development of photovoltaic technology, this type of cell has attracted widespread attention due to its high efficiency and good photoelectric conversion efficiency. In the manufacturing process of heterojunction cells, coating technology is a key step, and the uniformity and accuracy of the film thickness directly affect the performance and stability of the cell.

[0003] During the repeated coating process, if the substrate is not replaced and cleaned regularly, the film thickness will be more than 10um and cracks will appear. In some serious cases, powder will fall off. The vacuum equipment coating process requires very high cleanliness. The presence of dust will cause pollution and poor coating. Therefore, the replacement of coating substrates and maintenance and cleaning need to be standardized. However, the industry generally uses production capacity and process times to estimate the maintenance cycle of substrates, which is not conducive to the stability of production line performance.

[0004] The existing technologies mainly include measurement methods based on professional instruments and estimation methods based on statistics. The former relies on traditional measuring instruments, such as spectrometers and laser interferometers, but this method has disadvantages such as complex operation, high cost, and poor real-time performance, and cannot meet the needs of large-scale production. The latter estimates the substrate coating thickness by counting the number of substrate coating times or the cumulative output of the machine. This method has relatively low estimation accuracy and there is also the problem of inaccurate statistical results when the machine is abnormal or in a non-production coating situation.

[0005] Therefore, there is an urgent need for a film thickness monitoring technology that can improve production efficiency, reduce costs and have high detection accuracy. Summary of the invention

[0006] The purpose of this application is to provide a film thickness monitoring technology that can improve production efficiency, reduce costs and has high detection accuracy.

[0007] In a first aspect, the present application provides a method for monitoring the coating thickness of a vacuum carrier. The method comprises: before starting coating, fixing a weighing piece to a fixing groove of the carrier, wherein after the weighing piece is fixed, its target surface is flush with the coating surface of the carrier, and the target surface is consistent with the opening of the fixing groove on the coating surface; starting coating, and stopping coating after a period of time; after stopping coating, removing the weighing piece from the carrier, and measuring the weight of the weighing piece; and determining the current coating thickness according to the weight measurement result of the weighing piece.

[0008] In some embodiments, the weight measurement result includes a weight change of the weighing piece, and determining the current coating thickness based on the weight measurement result of the weighing piece includes: determining the weight of the film layer currently covering the target surface based on the weight change of the weighing piece; determining the current coating thickness based on the weight of the film layer currently covering the target surface.

[0009] In some embodiments, the coating thickness is determined by the following formula:

[0010]

[0011] Wherein, D represents the coating thickness, M represents the weight of the film layer covering the target surface, ρ represents the mass density of the film layer, and S represents the area of ​​the target surface.

[0012] In some embodiments, the weighing member is block-shaped.

[0013] In some embodiments, the membrane layer is composed of silicon atoms, and the weighing element includes at least one material selected from the group consisting of metal, graphite, and ceramic.

[0014] In some embodiments, the carrier has a plurality of fixing grooves distributed in different areas of the carrier, each fixing groove is used to install a weighing piece, and the weighing piece corresponding to the fixing groove in any area is used to determine the coating thickness of the area.

[0015] In a second aspect, an embodiment of the present application provides a method for monitoring the coating thickness of a vacuum carrier. The method is executed by a processor, and includes: obtaining a weight detection result of a weighing piece; and determining the current coating thickness according to the weight measurement result of the weighing piece. Before starting coating, the weighing piece is fixed to a fixing groove of the carrier, wherein after the weighing piece is fixed, its target surface is flush with the coating surface of the carrier, and the target surface coincides with the opening of the fixing groove on the coating surface. After stopping coating, the weighing piece is removed from the carrier and its weight is measured.

[0016] In a third aspect, an embodiment of the present application provides a computing device, comprising a processor and a memory. The memory stores a computer program, and when the processor executes the computer program, the method for monitoring the thickness of the vacuum carrier coating as described in the first aspect or the second aspect is implemented.

[0017] In a fourth aspect, an embodiment of the present application provides a system for monitoring the coating thickness of a vacuum carrier. The system includes an acquisition module and a determination module. The acquisition module is used to obtain the weight detection result of the weighing piece. The determination module is used to determine the current coating thickness based on the weight measurement result of the weighing piece. Before coating, the weighing piece is fixed to the fixing groove of the carrier, wherein after the weighing piece is fixed, its target surface is flush with the coating surface of the carrier, and the target surface coincides with the opening of the fixing groove on the coating surface. After stopping the coating, the weighing piece is removed from the carrier and its weight is measured.

[0018] In a fifth aspect, an embodiment of the present application provides a carrier having a fixing groove for fixing a weighing piece, and the weighing piece is applied to the method for monitoring the coating thickness of a vacuum carrier as described in the first aspect or the second aspect.

[0019] The embodiments of the present application have at least the following beneficial effects:

[0020] (1) It is easy to implement without the need for professional instruments, which can improve production efficiency and reduce costs;

[0021] (2) The detection accuracy is high, and the substrate cleaning and maintenance cycle can be standardized according to the substrate film thickness;

[0022] (3) By monitoring the film thickness, the defect rate of the production line can be reduced and the output capacity can be stabilized;

[0023] (4) Improved material utilization and reduced rework costs caused by defects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0025] Figure 1 is an exemplary flow chart of a method for monitoring the thickness of a vacuum carrier coating according to some embodiments of the present specification.

[0026] Figure 2 It is a cross-sectional schematic diagram of a carrier board shown in some embodiments of this specification.

[0027] Figure 3 is an exemplary flow chart of a process for estimating coating thickness according to some embodiments of the present specification.

[0028] Figure 4 It is a schematic diagram of the distribution of fixing grooves according to some embodiments of this specification.

[0029] Figure 5It is an exemplary flow chart of a method for monitoring the thickness of a vacuum carrier coating according to other embodiments of this specification.

[0030] Figure 6 is an exemplary block diagram of a method for monitoring the thickness of a vacuum carrier coating according to some embodiments of the present specification.

[0031] Figure 7 is a schematic diagram of the structure of an exemplary computing device. DETAILED DESCRIPTION

[0032] In order to more clearly understand the above-mentioned purposes, features and advantages of the present application, the embodiments of the present application will be further described below. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0033] In the following description, many specific details are set forth to facilitate a full understanding of the present application, but the present application can also be implemented in other ways different from those described herein. Obviously, the embodiments in the specification are only part of the embodiments of the present application, not all of the embodiments.

[0034] Figure 1 FIG. 1 is an exemplary flow chart of a method for monitoring the thickness of a vacuum carrier coating according to some embodiments of this specification. Figure 1 As shown, process 100 includes the following steps.

[0035] Step 110, before coating, fix the weighing piece to the fixing groove of the carrier plate.

[0036] After the weighing piece is fixed, its target surface is flush with the coating surface of the carrier, and the target surface matches the opening of the fixing groove on the coating surface. This setting makes the target surface of the weighing piece the only surface that can cover the film layer, so as to facilitate accurate estimation of the coating thickness. The coating surface refers to the surface of the carrier used to place the substrate (such as a silicon wafer) to be coated. Figure 2 The cross-section diagram of the carrier plate and the weight measuring piece. Figure 2 The weighing piece 300 is block-shaped, the shape and size of the fixing groove 250 match the shape and size of the weighing piece 300, and the target surface 300-A of the weighing piece 300 is flush with the coating surface 200-A of the carrier 200. The present application does not impose too many restrictions on the shape of the weighing piece. Under the premise of meeting the above settings, the weighing piece can be of various shapes, such as trapezoidal, rhombic, hemispherical, etc.

[0037] It is worth noting that the influence of the thickness of the substrate on the measurement error can be ignored, that is, it can be assumed that the substrate surface, the coating surface of the carrier and the target surface of the weighing device are flush. Based on this, it can be assumed that the film thickness of the substrate surface and the target surface of the weighing device are equal after the same coating time.

[0038] Regarding the material selection of the weighing piece, factors such as the influence on the coating (for example, whether it participates in the gas reaction in the coating chamber), cost, etc. can be considered. As an example only, when the film layer is composed of silicon atoms, the weighing piece can include at least one material of metal, graphite, and ceramic.

[0039] Step 120, start coating, and stop coating after a period of time.

[0040] The coating time in step 120 can be set based on experience. For example, it is usually necessary to repeat the process 100, and in the first execution, a longer coating time is set based on experience, and in each subsequent execution, a shorter coating time is set to gradually approach the expected film thickness.

[0041] Step 130, after stopping the coating, the weighing piece is removed from the carrier plate and the weight of the weighing piece is measured.

[0042] Based on the above settings, it can be considered that the film thickness of the target surface of the weighing piece is equal to the film thickness of the substrate. As the coating process progresses, the film layer covering the target surface of the weighing piece becomes thicker and thicker, and the weight of the weighing piece also increases accordingly. Therefore, the weight change of the weighing piece can be regarded as the weight of the film layer covering the target surface of the weighing piece, that is, the weight of the film layer covering the substrate. When the weight of the film layer covering the substrate is determined, the current coating thickness can be determined in combination with known related parameters (mass density of the film layer and area of ​​the target surface). It should be understood that the mass of the film layer is evenly distributed.

[0043] Step 140, determining the current coating thickness according to the weight measurement result of the weighing piece.

[0044] In some embodiments, reference Figure 3 , step 140 further includes step 310 and step 320.

[0045] Step 310: Determine the weight of the film layer currently covering the target surface according to the weight change of the weighing piece.

[0046] As mentioned above, under the same conditions, the weight of the film layer covering the target surface of the weighing piece is the weight of the film layer covering the substrate.

[0047] Step 320, determining the current coating thickness according to the weight of the film layer currently covering the target surface.

[0048] In some embodiments, the coating thickness can be determined by the following formula:

[0049]

[0050] Where D is the coating thickness, M is the weight of the film layer covering the target surface, ρ is the mass density of the film layer, and S is the area of ​​the target surface. For a film layer composed of a single atom, the mass density ρ can be replaced by the product of the mass of the single atom and the density of the atom, as shown below:

[0051]

[0052] Here, m represents the mass of a single atom (such as a silicon atom), and N represents the atomic density (i.e. the number of atoms per unit volume).

[0053] In some embodiments, a mapping table of the weight change of the weighing piece and the coating thickness can be pre-established, and the mapping table can be determined according to formula (1) and the required detection accuracy. Similarly, a mapping table of the weight of the weighing piece and the coating thickness can be established, and the mapping table can be determined according to formula (1) and the required detection accuracy. It can be understood that the weight change of the weighing piece in the mapping table of the weight change of the weighing piece and the coating thickness is superimposed on the net weight of the weighing piece (excluding the original weight of the film layer), and the mapping table of the weight of the weighing piece and the coating thickness can be obtained.

[0054] In some embodiments, a film thickness prediction model can be established by machine learning methods. Specifically, a large number of samples can be collected from a real production environment, each sample including the weight of a weighing piece (or weight change) as a model input and the film thickness as a sample label, wherein the sample label can be obtained with the aid of professional instruments. The initial model (such as a linear model) is trained using the sample set until a film thickness prediction model that meets the accuracy requirements is obtained. Furthermore, the weight of the weighing piece (or weight change) is input into the film thickness prediction model to obtain the coating thickness.

[0055] The process 100 may be a manual process, an automated process or a semi-automated process. For example, the fixing, removal and weighing of the weighing piece may be automatically performed by a mechanical device, and the entire process may be performed by a controller.

[0056] In some embodiments, the carrier has a plurality of fixed slots, which are distributed in different areas of the carrier, each of which is used to install a weighing piece, and the weighing piece corresponding to the fixed slot in any area is used to determine the coating thickness of the area. Figure 4 The rectangular carrier 200 has five fixing grooves 250 distributed in the central area of ​​the carrier and four areas surrounding the central area.

[0057] Figure 5 500 is an exemplary flow chart of a method for monitoring the thickness of a vacuum carrier coating according to other embodiments of this specification. Process 500 is executed by a processor. Figure 5 As shown, process 500 includes the following steps.

[0058] Step 510, obtaining the weight detection result of the weighing piece.

[0059] Before coating begins, the weighing piece is fixed to the fixing groove of the carrier plate, wherein, after the weighing piece is fixed, its target surface is flush with the coating surface of the carrier plate, and the target surface coincides with the opening of the fixing groove on the coating surface. After coating stops, the weighing piece is removed from the carrier plate and its weight is measured.

[0060] Step 520, determining the current coating thickness according to the weight measurement result of the weighing piece.

[0061] For more details about process 500 and its steps, please refer to Figure 1 and its related description.

[0062] It should be noted that the above description of the process is only for example and explanation, and does not limit the scope of application of the present application. For those skilled in the art, various modifications and changes can be made to the process under the guidance of the present application.

[0063] Figure 6 is an exemplary block diagram of a system for monitoring the thickness of a vacuum carrier coating according to some embodiments of the present specification. The system can be implemented as at least a part of a computing device by software, hardware, or a combination of both. Figure 6 As shown, the system 600 includes an acquisition module 610 and a determination module 620 .

[0064] The acquisition module 610 is used to obtain the weight detection result of the weighing piece. Before coating, the weighing piece is fixed to the fixing groove of the carrier plate, wherein after the weighing piece is fixed, its target surface is flush with the coating surface of the carrier plate, and the target surface is consistent with the opening of the fixing groove on the coating surface. After stopping coating, the weighing piece is removed from the carrier plate and its weight is measured.

[0065] In some embodiments, the acquisition module 610 is further used to: fix the weighing piece in the fixing groove of the carrier before starting coating; start coating and stop coating after a period of time; after stopping coating, remove the weighing piece from the carrier and measure the weight of the weighing piece.

[0066] The determination module 620 is used to determine the current coating thickness according to the weight measurement result of the weighing piece.

[0067] For more details about the system 600 and its modules, please refer to Figure 1 , Figure 5 and its related description.

[0068] It should be noted that the above division of functional modules is only for example. For those skilled in the art, after understanding the system principles, they can arbitrarily combine, split, replace equivalent modules, and add or omit one or more modules without violating the system principles.

[0069] Figure 7 is a schematic diagram of an exemplary computing device. Figure 7 As shown, the computing device 700 includes a processor 710 and a memory 720. The memory 710 stores a computer program. When the processor 710 executes the computer program, the method for monitoring the coating thickness of the vacuum carrier provided in the embodiment of the present application is implemented.

[0070] refer to Figure 2 and Figure 4 The embodiment of the present application also provides a carrier plate 200, the carrier plate 200 has a fixing groove 250 for fixing a weighing piece 300, and the weighing piece 300 is applied to the method for monitoring the coating thickness of the vacuum carrier provided in the embodiment of the present application (process 100 or process 500).

[0071] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusions, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to the process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "including a..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0072] The above is only an embodiment of the present application, and the embodiment enables those skilled in the art to understand and implement the present application. Various modifications to the embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments described herein, but will conform to the widest scope consistent with the principles and features disclosed herein.

Claims

1. A method for monitoring the thickness of a vacuum carrier coating, characterized in that: include: Before starting the coating, fix the weighing piece to the fixing groove of the carrier plate, wherein after the weighing piece is fixed, its target surface is flush with the coating surface of the carrier plate, and the target surface is consistent with the opening of the fixing groove on the coating surface; Start coating, and stop coating after a period of time; After the coating is stopped, the weighing piece is removed from the carrier plate, and the weight of the weighing piece is measured; The current coating thickness is determined according to the weight measurement result of the weighing piece.

2. The method according to claim 1, characterized in that The weight measurement result includes a weight change of the weighing piece, and determining the current coating thickness according to the weight measurement result of the weighing piece includes: Determining the weight of the film layer currently covering the target surface according to the weight change of the weighing piece; The current coating thickness is determined according to the weight of the film layer currently covering the target surface.

3. The method according to claim 2, characterized in that The coating thickness is determined by the following formula: Wherein, D represents the coating thickness, M represents the weight of the film layer covering the target surface, ρ represents the mass density of the film layer, and S represents the area of ​​the target surface.

4. The method according to claim 1, characterized in that The weighing piece is in block shape.

5. The method according to claim 1, characterized in that The film layer is composed of silicon atoms, and the weighing piece includes at least one material selected from metal, graphite and ceramic.

6. The method according to claim 1, characterized in that The carrier plate has a plurality of fixing grooves, and the plurality of fixing grooves are distributed in different areas of the carrier plate. Each fixing groove is used to install a weighing piece, and the weighing piece corresponding to the fixing groove in any area is used to determine the coating thickness of the area.

7. A method for monitoring the thickness of a vacuum carrier coating, characterized in that: The method is executed by a processor and includes: Obtaining the weight detection result of the weighing piece; before starting the coating, the weighing piece is fixed to the fixing groove of the carrier plate, wherein after the weighing piece is fixed, its target surface is flush with the coating surface of the carrier plate, and the target surface is consistent with the opening of the fixing groove on the coating surface; after stopping the coating, the weighing piece is removed from the carrier plate and its weight is measured; The current coating thickness is determined according to the weight measurement result of the weighing piece.

8. A computing device, characterized in that The method comprises a processor and a memory, wherein a computer program is stored in the memory, and when the processor executes the computer program, the method for monitoring the thickness of the coating on the vacuum carrier as claimed in any one of claims 1 to 7 is implemented.

9. A system for monitoring the thickness of a vacuum carrier coating, characterized in that: include: an acquisition module, used for acquiring a weight detection result of a weighing piece; before coating, the weighing piece is fixed to a fixing groove of a carrier plate, wherein after the weighing piece is fixed, its target surface is flush with the coating surface of the carrier plate, and the target surface is consistent with an opening of the fixing groove on the coating surface; after coating is stopped, the weighing piece is removed from the carrier plate and its weight is measured; The determination module is used to determine the current coating thickness according to the weight measurement result of the weighing piece.

10. A carrier board, characterized in that: The carrier plate has a fixing groove for fixing a weighing piece, and the weighing piece is applied to the method for monitoring the coating thickness of a vacuum carrier plate according to any one of claims 1 to 7.

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