Mask assembly, evaporation device and control method of mask assembly

Abstract

The application provides a mask assembly, an evaporation device and a control method of the mask assembly, and aims to improve the precision of the evaporation film layer of a display panel. The support table of the mask assembly has a support surface. The fixed part is arranged on the side facing the support surface. The mask is arranged on the side facing the support surface, and the mask comprises a first edge part extending along a first direction, and the first edge part is fixed to the fixed part. The stretching assembly is arranged on the support table, and the stretching assembly is connected to the fixed part through a tension sensor. The tension sensor is used to detect the tension between the stretching assembly and the fixed part. The control unit is used to control the stretching assembly to increase or decrease the force provided by the fixed part along a second direction according to the tension detected by the tension sensor. The second direction is a direction from the center area of the mask to the edge area and perpendicular to the first direction. The mask assembly provided by the application can improve the manufacturing precision of the display panel.

Description

Technical Field

[0001] This application relates to the field of display panel manufacturing technology, specifically to a mask assembly, a vapor deposition apparatus, and a control method for the mask assembly. Background Technology

[0002] In the fabrication of Organic Light-Emitting Diode (OLED) display panels, a high-precision fine metal mask (FMM) is typically used to deposit red, green, and blue sub-pixels, electrodes, and other film layers onto predetermined positions on the substrate via an evaporation deposition process. However, during evaporation deposition, the mask, especially its central area, sags due to gravity. The larger the display panel area, the greater the sag in the central area of ​​the mask, which can easily lead to inaccuracies in the position and thickness of the deposited film layers, resulting in a low yield rate for the display panel. Summary of the Invention

[0003] This application provides a mask assembly, a vapor deposition apparatus, and a control method for the mask assembly, which are used to solve the problem of how to improve the accuracy of the vapor deposition film layer of a display panel.

[0004] To achieve the above objectives, the embodiments of this application adopt the following technical solutions:

[0005] In a first aspect, embodiments of this application provide a mask assembly, which includes a support platform, a fixing part, a mask, a stretching assembly, and a control unit. The support platform has a support surface. The fixing part is disposed on the side facing the support surface. The mask is disposed on the side facing the support surface and includes a first edge portion extending along a first direction, which is fixed to the fixing part. The stretching assembly is disposed on the support platform and connected to the fixing part via a tension sensor; the tension sensor is used to detect the tension between the stretching assembly and the fixing part. The control unit is electrically connected to both the stretching assembly and the tension sensor, and is used to: if the tension detected by the tension sensor is greater than or equal to a first tension threshold, control the stretching assembly to reduce the force provided by the stretching assembly to the fixing part along a second direction; if the tension detected by the tension sensor is less than or equal to a second tension threshold, control the stretching assembly to increase the force provided by the stretching assembly to the fixing part in the second direction; wherein the second direction is a direction from the center region of the mask to the edge region and perpendicular to the first direction, and the second tension threshold is less than the first tension threshold.

[0006] In some possible implementations of the first aspect, the tensioning assembly includes a connector and a drive mechanism. The connector extends along a first direction and is connected to the fixing part via a tension sensor. The drive mechanism is connected to the support surface and is drively connected to the connector. The drive mechanism is used to move the connector along a second direction and is electrically connected to the control unit.

[0007] In some possible implementations of the first aspect, the drive mechanism includes a motor and a lead screw. The motor is fixed to a support platform and is electrically connected to a controller. The lead screw extends in a second direction, with one end connected to the output of the motor and the other end threadedly connected to a connector.

[0008] In some possible implementations of the first aspect, the drive mechanism includes a shape memory alloy component extending along a second direction, one end of which is connected to a connector and the other end is fixed relative to a support platform, and the shape memory alloy component is electrically connected to a control unit.

[0009] In some possible implementations of the first aspect, the drive mechanism further includes a first jaw and a second jaw. The first jaw is fixed to the connector, and one end of the shape memory alloy part is clamped and fixed to the first jaw. The second jaw is fixed to the support platform, and the other end of the shape memory alloy part is clamped and fixed to the second jaw.

[0010] In some possible implementations of the first aspect, the fastener includes a clamping portion, and a first edge portion is clamped and fixed to the clamping portion.

[0011] In some possible implementations of the first aspect, the first edge portion has a plurality of limiting grooves spaced apart along a first direction. The clamping portion includes two opposing clamping surfaces, which respectively abut against two surfaces of the first edge portion. The clamping surfaces have a plurality of limiting blocks, and one limiting block is fitted into a limiting groove.

[0012] In some possible implementations of the first aspect, the mask assembly further includes a guide rail fixed to the support surface and extending along a second direction; both the fixing part and the connector are slidably connected to the guide rail along the second direction.

[0013] Secondly, embodiments of this application provide a vapor deposition apparatus, which includes a substrate and a mask assembly. The mask assembly is any of the mask assemblies described above, and the masks are stacked on one side of the substrate.

[0014] Thirdly, embodiments of this application provide a control method for a mask assembly, used to control the mask assembly described in any of the above implementations. The method includes: controlling a tensioning component to provide a force in a second direction to a fixing component. If the tension detected by a tension sensor is greater than or equal to a first tension threshold, the corresponding tensioning component is controlled to reduce the force provided by the fixing component; if the tension detected by the tension sensor is less than or equal to a second tension threshold, the corresponding driving structure is controlled to increase the force provided by the fixing component, wherein the second tension threshold is less than the first tension threshold.

[0015] The mask assembly, evaporation apparatus, and control method for the mask assembly provided in this application have the following characteristics:

[0016] Beneficial effects:

[0017] The mask assembly provided in this application involves positioning a fixing part and a mask on the side facing the support surface of a support platform. The first edge of the mask is fixed to the fixing part. A tensioning assembly positioned on the support platform is connected to the fixing part via a tension sensor. This tensioning assembly provides a second-direction force to the fixing part, causing the first edge of the mask to be flattened by the second-direction force. Therefore, when using this mask for vapor deposition, the mask can be completely adhered to the substrate, thereby improving the accuracy of the position and thickness of the vapor-deposited film and increasing the yield of the display panel.

[0018] Based on this, by electrically connecting the control unit to both the tension sensor and the tensioning assembly, the control unit can control the tensioning assembly to reduce the force provided by the fixing part in the second direction when the tension detected by the tension sensor is greater than or equal to a first tension threshold, and control the tensioning assembly to increase the force provided by the fixing part in the second direction when the tension detected by the tension sensor is less than or equal to a second tension threshold. This ensures that the mask is always in a flattened state, guaranteeing the accuracy of the position and thickness of the formed film layer, and also prevents the mask from deforming and being damaged due to excessive force applied to it over a prolonged period.

[0019] The beneficial technical effects of the vapor deposition apparatus and mask assembly control method provided in this application are the same as those of the mask assembly provided in this application, and will not be repeated here. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the substrate and photomask for related technologies;

[0021] Figure 2 A top view of a portion of the structure of the vapor deposition apparatus provided in some embodiments of this application;

[0022] Figure 3 for Figure 2A front view of a portion of the structure of the vapor deposition apparatus shown.

[0023] Figure 4 for Figure 3 A plan view of the mask plate of the vapor deposition apparatus shown;

[0024] Figure 5 for Figure 3 A top view of a partial structure of the vapor deposition apparatus shown.

[0025] Figure 6 for Figure 3 A top view of another part of the vapor deposition apparatus shown;

[0026] Figure 7 for Figure 3 A cross-sectional view of a partial structure of the vapor deposition apparatus shown;

[0027] Figure 8 This is a schematic diagram of the control method of the vapor deposition apparatus provided in some embodiments of this application.

[0028] Figure label:

[0029] 100 - Evaporation deposition apparatus;

[0030] 10-Shell; 10a-Receiving cavity; 10a1-Vapor deposition cavity; 10a2-Alignment cavity; 11-Isolation door;

[0031] 20 - Evaporation source;

[0032] 30 - Substrate assembly; 31 - Substrate; 31a - First surface; 31b - Second surface; 32 - Conveying device; 321 - Conveying mechanism; 322 - Tray;

[0033] 40-Mask assembly; 41-Mask; 41a-Opening; 411-First edge; 411a-Limiting groove; 412-Second edge; 413-Third edge; 414-Fourth edge; 415-Functional part; 42-Support platform; 42a-Support surface; 43-Fixing part; 431-Clamping part; 431a-Clamping surface; 431b-Limiting block; 44-Tension assembly; 441-Connector; 442-Drive mechanism; 4421-Shape memory alloy part; 4422-First claw; 4423-Second claw; 4424-Bracket; 4425-Motor; 4426-Lead screw; 45-Force sensor; 46-Guide rail;

[0034] 50 - Alignment mechanism. Detailed Implementation

[0035] In the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation" and "connection" should be interpreted broadly. For example, "connection" can be a detachable connection or a non-detachable connection; it can be a direct connection or an indirect connection through an intermediate medium.

[0036] In the embodiments of this application, it should be understood that the directional terms mentioned, such as "up", "down", "left", "right", "inner", "outer", etc., are only for reference to the direction of the accompanying drawings. Therefore, the directional terms used are for better and clearer explanation and understanding of the embodiments of this application, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0037] In the embodiments of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" and "second" may explicitly or implicitly include one or more of that feature.

[0038] In embodiments of this application, 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 limitation, 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 that element.

[0039] In the embodiments of this application, "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0040] In the embodiments of this application, it should be noted that the descriptions of "vertical" and "parallel" respectively indicate approximately vertical and approximately parallel within a certain error range. This error range can be a range with a deviation angle of less than or equal to 5°, 8° or 10° relative to absolute verticality and absolute parallelism, respectively, and is not specifically limited here.

[0041] In related technologies, during the fabrication of Organic Light-Emitting Diode (OLED) display panels, a high-precision fine metal mask (FMM) is typically used to deposit pixel layers such as red, green, and blue sub-pixels, as well as electrode layers, onto predetermined locations on the substrate through an evaporation deposition process. However, please refer to... Figure 1 , Figure 1 This is a schematic diagram of the structure of the substrate 31 and the mask 41 in the related technology. During the evaporation deposition, the mask 41, especially the central area of ​​the mask 41, will sag due to its own gravity. The larger the area of ​​the display panel, the greater the sag of the central area of ​​the mask 41. There is a large gap between the mask 41 and the substrate 31, which leads to inaccurate position and thickness of the film layer formed by evaporation, resulting in a low yield of the display panel.

[0042] To resolve the above issues, please refer to the following: Figure 2 and Figure 3 , Figure 2 This is a top view of a portion of the structure of the vapor deposition apparatus 100 provided in some embodiments of this application. Figure 3 for Figure 2 A front view of a portion of the structure of the vapor deposition apparatus 100 shown. This application provides a vapor deposition apparatus 100. The vapor deposition apparatus 100 includes a housing 10, a vapor deposition source 20, a substrate assembly 30, a mask assembly 40, an alignment mechanism 50, and a controller (not shown in the figure).

[0043] The housing 10 surrounds a receiving cavity 10a, which is a vacuum cavity. At least a portion of the vapor deposition source 20, the mask assembly 40, and the substrate assembly 30 are disposed within the receiving cavity 10a. Specifically, the receiving cavity 10a may include a vapor deposition cavity 10a1 and an alignment cavity 10a2, which are separated from the vapor deposition cavity 10a1 by an opening and closing isolation door 11. The vapor deposition source 20 is disposed within the vapor deposition cavity 10a1, and the alignment mechanism 50 is disposed within the alignment cavity 10a2. In some other embodiments, the receiving cavity 10a may not include the alignment cavity 10a2, and the alignment mechanism 50 may also be disposed within the vapor deposition cavity 10a1.

[0044] The substrate assembly 30 includes a substrate 31 and a conveying device 32. The substrate 31 can be a glass substrate, thus possessing good rigidity and flatness, and can serve as a support substrate for the pixel layer and electrode layer. Furthermore, the substrate 31 also exhibits good high-temperature resistance and chemical stability, minimizing limitations on the manufacturing process of the display panel. The substrate 31 has a first surface 31a and a second surface 31b arranged along the thickness direction. Figure 3 and Figure 4In the embodiment shown, the first surface 31a is the lower surface and the second surface 31b is the upper surface.

[0045] A conveying device 32 is disposed on the housing 10, and includes a conveying mechanism 321 and a tray 322. A portion of the conveying mechanism 321 is movable relative to the housing 10 in a direction parallel to the substrate 31. Specifically, the conveying mechanism 321 can be a belt conveyor. The tray 322 is disposed on the conveying mechanism 321. Specifically, the tray 322 can be disposed on the conveying mechanism 321 by means of snap-fit, threaded connection, etc. Based on this, the substrate 31 can be fixed to the tray 322, so that the conveying device 32 can convey the substrate 31 to a preset position in the receiving cavity 10a. For example, the substrate 31 can be conveyed to the alignment cavity 10a2 for alignment with the mask 41, or it can be conveyed to the evaporation cavity 10a1 for evaporation of the pixel layer and / or electrode layer.

[0046] The mask assembly 40 includes a mask 41, a support platform 42, a fixing part 43, a tension assembly 44, a tension sensor 45, and a control unit (not shown in the figure). The control unit may be part of the aforementioned controller. In some other embodiments, the control unit may also be a separate control circuit electrically connected to the aforementioned controller.

[0047] Please refer to the following: Figure 3 and Figure 4 , Figure 4 for Figure 3 The diagram shows a plan view of the mask plate 41 in the vapor deposition apparatus 100. The mask plate 41 can be a metal structural component. Specifically, the mask plate 41 can be an Invar alloy structural component, a stainless steel structural component, or other metal structural components. The mask plate 41 is disposed on the side facing the first surface 31a of the substrate 31, that is, when the vapor deposition apparatus 100 is in alignment or vapor deposition state, the mask plate 41 is stacked and disposed below the substrate 31. The mask plate 41 can be generally rectangular in shape, and the mask plate 41 can include a first edge portion 411, a second edge portion 412, a third edge portion 413, a fourth edge portion 414, and a functional portion 415. The first edge portion 411, the second edge portion 412, the third edge portion 413, and the fourth edge portion 414 are connected end to end to form a rectangular ring, and all of them are connected to the functional portion 415. The first edge portion 411 and the third edge portion 413 extend along a first direction, while the second edge portion 412 and the fourth edge portion 414 extend along a second direction. In other embodiments, the mask plate 41 may also be in other shapes such as triangle, rhombus, or circle, with the shape of the edge portion matching the shape of the outer edge of the mask plate 41.

[0048] Based on this, the mask plate 41 has a plurality of openings 41a, which are opened in the functional part and penetrate the mask plate 41 along the thickness direction of the mask plate 41, for forming a film layer with a preset pattern on the substrate 31 by the vapor deposition material.

[0049] A support platform 42 is disposed within the housing 10. The support platform 42 has a support surface 42a, which is substantially parallel to the mask 41. The mask 41 is disposed on the side facing the support surface 42a. The support platform 42 can be arranged around the mask 41 to provide a channel for the vapor deposition material. The support platform 42 can be a continuous ring structure or a discontinuous ring structure. The support platform 42 may include an adjustment structure (not shown in the figure) to move the mask 41 relative to the housing 10. Specifically, the support platform 42 can move the mask 41 in a direction perpendicular to the mask 41 (vertical direction) to move the mask 41 closer to or further away from the substrate 31. The support platform 42 can also move the mask 41 in a direction parallel to the mask 41 to align the mask 41 with the substrate 31.

[0050] The fixing part 43 is disposed on the side facing the support surface 42a. Specifically, the fixing part 43 can extend along a first direction and the extension length is approximately the same as the extension length of the first edge part 411. Based on this, the first edge part 411 of the mask plate 41 is fixed to the fixing part 43. In some other embodiments, the length of the fixing part 43 may also be greater than or less than the length of the first edge part 411.

[0051] A tensioning assembly 44 is disposed on a support platform 42. The tensioning assembly 44 is connected to a fixing part 43 via a tension sensor 45, which detects the tension between the tensioning assembly 44 and the fixing part 43. The tensioning assembly 44 provides a second-direction force to the fixing part 43, causing the mask plate 41 to be flattened by the second-direction force. In some examples, the tension sensor 45 can be an S-shaped tension sensor. In other examples, the tension sensor 45 can also be a plate ring type tension sensor.

[0052] The control unit is electrically connected to the tension assembly 44 and the tension sensor 45. The controller is used to: if the tension detected by the tension sensor 45 is greater than or equal to the first tension threshold, control the tension assembly 44 to reduce the force provided by the fixing part 43 in the second direction; if the tension detected by the tension sensor 45 is less than or equal to the second tension threshold, control the tension assembly 44 to increase the force provided by the fixing part 43 in the second direction; wherein, the second direction is the direction from the center region of the mask plate 41 to the edge region and perpendicular to the first direction, and the second pressure threshold is less than the first pressure threshold.

[0053] It should be noted that the first tensile threshold can be selected based on the tensile strength of the mask plate 41 and can be obtained through experimental measurement; the second pressure threshold can be selected based on the material and size of the mask plate 41 and can be determined by experimental measurement to maintain the mask plate 41 in a flat state for a preset time.

[0054] In this way, by positioning the fixing part 43 and the mask 41 on the side facing the support surface 42a of the support platform 42, the first edge portion 411 of the mask 41 is fixed to the fixing part 43. The tensioning assembly 44, located on the support platform 42, is connected to the fixing part 43 via a tension sensor 45, allowing the tensioning assembly 44 to provide a second-direction force to the fixing part 43. This causes the first edge portion 411 of the mask 41 to be subjected to the second-direction force, resulting in the mask 41 being flattened. This allows the mask 41 to be completely bonded to the substrate 31, thereby improving the accuracy of the position and thickness of the vapor-deposited film layer and increasing the yield of the display panel.

[0055] Based on this, by electrically connecting the control unit to both the tension sensor 45 and the tension assembly 44, the control unit can control the tension assembly 44 to reduce the force in the second direction provided by the fixing part 43 when the tension detected by the tension sensor 45 is greater than or equal to a first tension threshold, and control the tension assembly 44 to increase the force in the second direction provided by the fixing part 43 when the tension detected by the tension sensor 45 is less than or equal to a second tension threshold. In this way, the mask plate 41 can always be kept flat to ensure the accuracy of the position and thickness of the formed film layer, and it can also prevent the mask plate 41 from deforming and being damaged due to excessive force applied to it for a long time.

[0056] Please refer to the following: Figure 3 and see Figure 5 , Figure 5 for Figure 3 This is a top view of a partial structure of the vapor deposition apparatus 100 shown. The stretching assembly 44 includes a connector 441 and a drive mechanism 442. The connector 441 extends along a first direction and is connected to the fixing part 43 via a tension sensor 45. Specifically, the connector 441 may have the same or different extension length as the fixing part 43. The two ends of the tension sensor 45 can be connected to the fixing part 43 and the connector 441 respectively by means of bonding, snap-fitting, threaded connection, etc. Based on this, the drive mechanism 442 is connected to the support surface 42a and is drively connected to the connector 441. The drive mechanism 442 is used to drive the connector 441 to move along a second direction and is electrically connected to the control unit.

[0057] In this way, the tension component 44 is connected to the tension sensor 45 through the connector 441. Thus, a structure that is connected to the drive mechanism 442 can be formed on the connector 441, without the need to form a corresponding structure on the tension sensor 45. This simplifies the design and assembly of the tension component 44 and makes it easier to replace the tension sensor 45, thus ensuring the detection accuracy of the tension sensor 45.

[0058] As one possible implementation, please continue reading. Figure 5 The drive mechanism 442 includes a shape memory alloy component 4421, which extends along a second direction. One end of the shape memory alloy component 4421 is connected to a connector 441, and the other end is fixed relative to a support platform 42. The shape memory alloy component 4421 is electrically connected to a control unit. It should be noted that the shape memory alloy component 4421 can undergo a phase transformation when the temperature changes, thereby changing its stress state. At low temperatures, the shape memory alloy component 4421 is in a martensitic phase, while as the temperature rises, it transforms from martensitic to austenitic and undergoes deformation and shrinkage.

[0059] In this way, the control unit can supply current to the shape memory alloy part 4421, causing it to shrink and deform due to the increased temperature caused by the heating effect of the current. This allows the connector 441 to provide a second-direction tension to the fixing part 43. The greater the current supplied to the shape memory alloy part 4421, the greater the shrinkage of the part, and the greater the tension provided to the fixing part, making it easier to keep the mask plate flat. Furthermore, after the vapor deposition layer is completed, stopping the current supply to the shape memory alloy part 4421 returns it to its initial state, reducing or stopping the tension provided to the fixing part 43. This facilitates precise control of the tension provided to the fixing part 43, keeping the mask plate 41 flat while reducing the risk of deformation and damage.

[0060] In some examples, there can be multiple tension sensors 45, spaced apart along a first direction, to provide multi-point connection between the connector 441 and the fixing part 43. Based on this, the shape memory alloy part 4421 is linear, and there are multiple shape memory alloy parts 4421, spaced apart along the first direction. Each shape memory alloy part 4421 can be individually controlled by a control unit to adjust the current flowing into the corresponding shape memory alloy part 4421 according to the tension detected by the tension sensors 45 at different locations. In this way, a more uniform tension can be provided to all the first edges 411 of the mask plate 41, ensuring that the mask plate 41 is subjected to uniform force.

[0061] In some embodiments, please continue reading Figure 5The drive mechanism 442 also includes a first jaw 4422 and a second jaw 4423. The first jaw 4422 is fixed to the connector 441, and one end of the shape memory alloy part 4421 is clamped and fixed to the first jaw 4422. The second jaw 4423 is fixed to the support platform 42, and the other end of the shape memory alloy part 4421 is clamped and fixed to the second jaw 4423. That is, both ends of the shape memory alloy part 4421 are connected to the connector 441 and the support platform 42 respectively through the first jaw 4422 and the second jaw 4423. Specifically, the first jaw 4422 and the second jaw 4423 can be fixed to the connector 441 and the support platform 42 respectively by means of bonding, threaded connection, etc. When there are multiple shape memory alloy parts 4421, all the second jaws 4423 can be fixed to the support platform 42 by a bracket 4424. It should be noted that insulation treatment is required between the first claw 4422 and the connector 441, and between the second claw 4423 and the support platform 42, such as coating the outer surfaces of the first claw 4422 and the second claw 4423 with insulating material.

[0062] This makes it easier to fix the shape memory alloy part 4421 to the connector 441 and the support platform 42, and also prevents the heat generated by conventional welding and other processes from being transferred to the shape memory alloy part 4421 and affecting its performance.

[0063] As another possible implementation, please refer to Figure 6 , Figure 6 for Figure 3 A top view of another part of the structure of the vapor deposition apparatus 100 shown. Figure 6 The illustrated embodiments and Figure 5 The difference in the illustrated embodiment is that the drive mechanism 442 includes a motor 4425 and a lead screw 4426. The motor 4425 is fixed to the support platform 42 and is electrically connected to the control unit. The lead screw 4426 extends in a second direction, with one end connected to the output end of the motor 4425 and the other end threadedly connected to the connector 441. In this way, by driving the lead screw 4426 with the motor 4425 to move the connector 441 in the second direction, the tension provided to the fixing part 43 can be increased; conversely, by driving the lead screw 4426 with the motor 4425 to move the connector 441 towards the center region of the mask plate 41, the tension provided to the fixing part 43 can be decreased. Thus, the overall structure of the drive mechanism 442 is simple, facilitating design, assembly, and control.

[0064] In some other embodiments, the tension assembly 44 may not include the connector 441, and the drive mechanism 442 may be directly connected to the tension sensor 45.

[0065] As one possible implementation, please refer to Figure 7 , Figure 7 for Figure 3 The diagram shows a partial cross-sectional view of the vapor deposition apparatus 100. The fixing part 43 includes a clamping part 431, in which the first edge portion 411 of the mask plate 41 is clamped and fixed. In this way, the mask plate 41 and the fixing part 43 are easy to assemble and disassemble, which is beneficial for quickly replacing different mask plates 41 to vapor deposit different film layers on the substrate 31.

[0066] In some embodiments, the clamping portion 431 includes two opposing clamping surfaces 431a, which are respectively pressed and fitted against two opposite surfaces of the first edge portion 411. The first edge portion 411 has a plurality of limiting grooves 411a spaced apart along a first direction, and the clamping surfaces 431a have a plurality of limiting blocks 431b, with one limiting block 431b fitted and accommodated within one limiting groove 411a.

[0067] In this way, based on the clamping surface 431a pressing and clamping the mask plate 41, the cooperation of the limiting block 431b and the limiting groove 411a can increase the reliability of the mask plate 41 being fixed to the fixing part 43, and can prevent the mask plate 41 from easily detaching from the fixing part 43 due to insufficient clamping force.

[0068] In some other embodiments, the first edge portion 411 may be fixed to the fixing portion 43 by adhesive or welding.

[0069] Based on the above, please refer to the following: Figure 3 , Figure 5 and Figure 6 The mask assembly 40 also includes a guide rail 46. The guide rail 46 is fixed to the support surface 42a and extends along the second direction. The fixing part 43 and the connector 441 are both slidably connected to the guide rail 46 along the second direction.

[0070] This prevents the tension provided by the stretching assembly 44 to the fixing part 43 from forming an angle with the second direction, which could lead to misalignment and deformation of the mask plate 41, resulting in inaccurate position and shape of the vapor-deposited film. Furthermore, it ensures that the tension measured by the tension sensor 45 is in the second direction, guaranteeing detection accuracy and thus control accuracy, ultimately ensuring the accuracy of the vapor-deposited film.

[0071] The fixing part 43, the tensioning assembly 44, the tension sensor 45, and the guide rail 46 used to provide a second-direction tension to the first edge 411 can form a tension control unit. Based on this, the second edge 412, the third edge 413, and the fourth edge 414 can also be connected to a tension control unit to simultaneously stretch the mask 41 to the outer periphery of the mask plate 41, so that the mask plate 41 is in a flattened state and is under balanced force.

[0072] Please see Figure 8 , Figure 8 This is a schematic diagram of the structure of a control method for a vapor deposition apparatus 100 provided in some embodiments of this application. This application provides a control method for a vapor deposition apparatus 100, used to control the aforementioned vapor deposition apparatus 100, and the control method includes steps S10-S80.

[0073] S10: Please refer to Figure 8 In step (a), the substrate 31 is fixed to the tray 322 of the conveying device 32, and the conveying mechanism 321 is controlled to convey the substrate 31 to the first preset position. Specifically, the first preset position can be a preset position within the alignment cavity 10a2.

[0074] S20: Please refer to Figure 8 In (b), the control support stage 42 drives the mask plate 41 and the aforementioned stretch control unit to move so that the mask plate 41 and the substrate 31 are stacked.

[0075] S30: Control the tensioning assembly 44 to provide a force in the second direction to the fixing part 43.

[0076] S40: Detect the tension between the tension component 44 and the fixing part 43.

[0077] S50: If the tension detected by the tension sensor 45 is greater than or equal to the first tension threshold, the corresponding tensioning component 44 is controlled to decrease to the force provided by the fixing part 43. If the tension detected by the tension sensor 45 is less than or equal to the second tension threshold, the corresponding driving structure is controlled to increase to the force provided by the fixing part 43. The second tension threshold is less than the first tension threshold. Steps S30-S50 constitute the control method for the mask assembly 40.

[0078] S60: Please refer to Figure 8 In step (c), the alignment mechanism 50 aligns the mask 41 and the substrate 31. Specifically, the alignment mechanism 50 may include a camera 51, which may be located above the substrate 31. The controller is electrically connected to the camera 51. The controller acquires image information of the substrate 31 and the mask 41 through the camera 51 and calculates the position information of corresponding reference points on the mask 41 and the substrate 31. This position information includes orientation and distance. If the position information does not meet the preset reference value, the controller controls the support stage 42 to move the mask 41 and the stretching control unit until the position information meets the preset reference value.

[0079] S70: The control conveying mechanism 321 and the support stage 42 respectively transport the substrate 31 and the mask 41 to the second preset position. Specifically, the second preset position can be above the evaporation source 20.

[0080] S80: Turn on the vapor deposition source 20 to evaporate the vapor deposition material and deposit it on the substrate 31 to form a film layer with a preset pattern.

[0081] In some other embodiments, the control method may not include step S70, and the first preset position in step S10 may be above the vapor deposition source 20 in the vapor deposition chamber 10a1.

[0082] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A mask assembly, characterized in that, include: A support platform having a support surface; A fixing part is provided on the side facing the supporting surface; A mask plate is disposed on the side facing the support surface, the mask plate includes a first edge portion extending along a first direction, and the first edge portion is fixed to the fixing portion; A tension assembly is disposed on the support platform and connected to the fixing part via a tension sensor; the tension sensor is used to detect the tension between the tension assembly and the fixing part. The control unit is electrically connected to both the stretching assembly and the tension sensor. The control unit is configured to: if the tension detected by the tension sensor is greater than or equal to a first tension threshold, control the stretching assembly to reduce the force provided by the fixing part along a second direction; if the tension detected by the tension sensor is less than or equal to a second tension threshold, control the stretching assembly to increase the force provided by the fixing part along a second direction; wherein the second direction is a direction from the center region of the mask plate to the edge region and perpendicular to the first direction, and the second tension threshold is less than the first tension threshold.

2. The mask assembly according to claim 1, characterized in that, The stretching component includes: A connector extending along the first direction, the connector being connected to the fixing part via the tension sensor; A drive mechanism is connected to the support surface and is drively connected to the connector. The drive mechanism is used to drive the connector to move along the second direction. The drive mechanism is electrically connected to the control unit.

3. The mask assembly according to claim 2, characterized in that, The drive mechanism includes: The motor is fixed to the support platform and is electrically connected to the control unit; A lead screw, which extends along the second direction, with one end connected to the output end of the motor and the other end connected to the connecting member via a threaded transmission.

4. The mask assembly according to claim 2, characterized in that, The drive mechanism includes: A shape memory alloy component extends along a second direction, one end of which is connected to the connector, and the other end is fixed relative to the support platform. The shape memory alloy component is electrically connected to the control unit.

5. The mask assembly according to claim 4, characterized in that, The drive mechanism also includes: The first claw is fixed to the connector, and one end of the shape memory alloy part is clamped and fixed to the first claw; The second claw is fixed to the support platform, and the other end of the shape memory alloy part is clamped and fixed to the second claw.

6. The mask assembly according to any one of claims 1-5, characterized in that, The fixing part includes a clamping part, and the first edge part is clamped and fixed to the clamping part.

7. The mask assembly according to claim 6, characterized in that, The first edge portion has a plurality of limiting grooves spaced apart along the first direction; The clamping part includes two opposing clamping surfaces, which respectively fit into two surfaces of the first edge portion. The clamping surfaces have multiple limiting blocks, and one of the limiting blocks is fitted into a limiting groove.

8. The mask assembly according to any one of claims 2-5, characterized in that, The mask assembly also includes: The guide rail is fixed to the support surface and extends along a second direction; both the fixing part and the connecting member are slidably connected to the guide rail along the second direction.

9. A vapor deposition apparatus, characterized in that, include: substrate; A mask assembly, wherein the mask assembly is any one of claims 1-8, and the mask is stacked on one side of the substrate.

10. A method for controlling a mask assembly, characterized in that, The method for controlling the mask assembly according to any one of claims 1-8, the method comprising: The tensioning assembly is controlled to provide a force in a second direction to the fixing part; If the tension detected by the tension sensor is greater than or equal to a first tension threshold, the tensioning component is controlled to reduce the force provided to the fixing part. If the tension detected by the tension sensor is less than or equal to a second tension threshold, the tensioning component is controlled to increase the force provided to the fixing part. The second tension threshold is less than the first tension threshold.

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