OLED panel vacuum annealing furnace

Abstract

The application discloses an OLED panel vacuum annealing furnace, which comprises a furnace body, an air inlet assembly, an air outlet assembly, a cooling assembly and a plurality of heating assemblies. The air inlet assembly is used for connecting an air source and introducing nitrogen into the chamber. The air outlet assembly is used for connecting a negative pressure device and extracting gas in the chamber. The cooling assembly comprises a pneumatic valve, a plurality of cooling pipelines and a plurality of support columns for supporting the OLED panel. Each of the cooling pipelines is provided with a plurality of air outlets. The heating assemblies are arranged below each of the cooling pipelines. The annealing furnace is provided with a plurality of heating assemblies above and below the panel. The annular heating mode can improve the temperature consistency during heating. The cooling assembly cools the panel from multiple directions, thereby improving the cooling speed. During the cooling process, the gas in the furnace is extracted, so that the solvent and water vapor volatilized from the substrate are prevented from being reattached to the panel surface in the cooling process, the consistency of the product is high, and the defective rate is low.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor manufacturing equipment technology, and specifically relates to an OLED panel vacuum annealing furnace. Background Technology

[0002] In OLED panel manufacturing, vacuum annealing is a core process for optimizing the thin film lattice, removing residual solvents from the organic layer, and releasing stress within the substrate. The annealing chamber must maintain a high-vacuum, oxygen-free environment and achieve precise heating and controlled cooling to ensure panel light emission uniformity, lifespan, and mass production yield. Existing OLED vacuum annealing equipment generally uses a unified heating system around the perimeter of the chamber, with all heating units adjusting their power synchronously. This makes it impossible to individually increase the heating power to compensate for the temperature in areas with rapid heat dissipation at the corners of the chamber. The temperature difference between the center and the edge of the chamber can reach more than 5°C, resulting in insufficient heating at the four corners of the substrate during annealing, inconsistent thin film crystallization, and significant differences in brightness and threshold voltage among panels in the same batch, making it difficult to guarantee product consistency. Secondly, the cooling structure is simple and has low cooling efficiency. The temperature difference between multi-layer substrates is large. Conventional equipment relies solely on nitrogen purging to cool the entire chamber without layered directional cooling pipelines. The airflow entering from one side of the chamber easily forms turbulence, causing the upper substrate to cool rapidly while the lower substrate cools slowly, resulting in significant differences in cooling rates among multi-layer substrates. Meanwhile, during the cooling stage, only nitrogen is filled in a sealed environment. The solvents and moisture volatilized from the substrate remain inside the cavity and re-adhere to the panel surface during the cooling process, exacerbating particle defects.

[0003] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to provide a vacuum annealing furnace for OLED panels to solve the temperature control problem during heating and the cooling problem during cooling.

[0005] To achieve the above objectives, a specific embodiment of the present invention provides an OLED panel vacuum annealing furnace, including a furnace body, an air inlet assembly, an exhaust assembly, a cooling assembly, and multiple heating assemblies. The furnace body has a hollow chamber inside. The air inlet assembly is located on one side of the furnace body and connects to the chamber, for connecting to an external gas source and introducing nitrogen into the chamber. The exhaust assembly is located on one side of the furnace body and connects to the chamber, for connecting to an external negative pressure device and extracting gas from the chamber. The cooling assembly includes a pneumatic valve, multiple sets of cooling pipes, and multiple support columns for supporting the OLED panel. The pneumatic valve is located outside the furnace body and connects to an external cooling gas source. The multiple sets of cooling pipes connect to the pneumatic valve and extend into the chamber, arranged longitudinally within the chamber. The multiple support columns are distributed on the remaining cooling pipes except for the top cooling pipe. Each set of cooling pipes has multiple air outlets. Multiple heating assemblies are located inside the furnace body and distributed below each cooling pipe.

[0006] In one or more embodiments of the present invention, the cooling assembly further includes a gas distribution block disposed between the pneumatic valve and the cooling pipeline, the gas distribution block being disposed outside the furnace body.

[0007] In one or more embodiments of the present invention, each group of cooling pipes forms a well-like self-supporting network structure within the cavity.

[0008] In one or more embodiments of the present invention, the exhaust assembly includes an exhaust main pipe, a plurality of exhaust branch pipes connected to the exhaust main pipe, and a plurality of exhaust connectors connected to the exhaust branch pipes. The exhaust main pipe is disposed outside the furnace body and is used for external connection of a negative pressure device, and the exhaust connectors are connected to the furnace body.

[0009] In one or more embodiments of the present invention, the air intake assembly includes an air intake main pipe, a plurality of air intake branch pipes connected to the air intake main pipe, and a plurality of air intake connectors connected to the air intake branch pipes. The air intake main pipe is disposed outside the furnace body and is used to connect to an external air source, and the air intake connectors are connected to the furnace body.

[0010] In one or more embodiments of the present invention, an insulated inner liner is disposed within the furnace body, and the support column is disposed within the insulated inner liner.

[0011] In one or more embodiments of the present invention, the heating temperature of the heating component is adjustable, a temperature sensor is provided inside the furnace body, and the heating component includes a heating sleeve and a heating wire wrapped inside the heating sleeve.

[0012] In one or more embodiments of the present invention, the furnace body is provided with an openable front door, which is opened and closed by a cylinder.

[0013] In one or more embodiments of the present invention, the furnace body is further provided with an openable back door, which is connected to the furnace body by a hinge, and a plurality of locking blocks are connected between the back door and the furnace body.

[0014] In one or more embodiments of the present invention, a plurality of liquid cooling pipes are provided on the outer wall of the furnace body, and each liquid cooling pipe is provided with a liquid inlet and a liquid outlet.

[0015] Compared with the prior art, the annealing furnace of the present invention has multiple heating components arranged above and below the panel, and the number is relatively large. This encircling heating method can improve the temperature consistency during heating. After the heating is completed and the cooling process begins, the cooling components cool the panel from multiple directions with the introduced cooling gas, which improves the cooling speed. At the same time, while the cooling gas is introduced, the exhaust component extracts the gas in the furnace to prevent the solvent and water vapor volatilized from the substrate from remaining in the furnace and re-adhering to the panel surface during the cooling process. Therefore, the product consistency is high and the defect rate is low. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of a vacuum annealing furnace for an OLED panel according to one embodiment of the present invention;

[0018] Figure 2 This is a schematic diagram of a cooling assembly according to an embodiment of the present invention;

[0019] Figure 3 This is a front view of a cooling assembly according to an embodiment of the present invention;

[0020] Figure 4 for Figure 3 A magnified view of a portion of the image;

[0021] Figure 5 This is a front view of an OLED panel vacuum annealing furnace according to an embodiment of the present invention;

[0022] Figure 6 This is a cross-sectional view of an OLED panel vacuum annealing furnace according to an embodiment of the present invention;

[0023] Figure 7 This is a schematic diagram of the furnace body in one embodiment of the present invention;

[0024] Figure 8This is a schematic diagram of the furnace body from another angle in one embodiment of the present invention;

[0025] Figure 9 This is a schematic diagram of an air intake assembly according to one embodiment of the present invention;

[0026] Figure 10 This is a schematic diagram of an exhaust assembly according to an embodiment of the present invention;

[0027] Figure 11 This is a schematic diagram of a heating component in one embodiment of the present invention;

[0028] Figure 12 This is a schematic diagram of an insulated inner liner in one embodiment of the present invention.

[0029] Explanation of key figure labels:

[0030] 1-Furnace body, 11-Front door, 12-Back door, 13-Hinge, 14-Locking block, 15-Liquid cooling pipe, 151-Liquid inlet, 152-Liquid outlet, 2-Air inlet assembly, 21-Air inlet main pipe, 22-Branch pipe, 23-Air inlet connector, 3-Exhaust assembly, 31-Exhaust main pipe, 32-Exhaust branch pipe, 33-Exhaust connector, 4-Cooling assembly, 41-Pneumatic valve, 42-Cooling pipe, 421-Air outlet, 43-Support column, 44-Support mesh, 45-Air distribution block, 5-Heating assembly, 51-Heating sleeve, 52-Heating wire, 6-Insulated inner liner, 7-Panel. Detailed Implementation

[0031] To enable those skilled in the art to better understand the technical solutions in this disclosure, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this disclosure.

[0032] like Figure 1 As shown, an OLED panel vacuum annealing furnace according to one embodiment of the present invention includes a furnace body 1, an air inlet assembly 2, an exhaust assembly 3, a cooling assembly 4, and a heating assembly 5. The furnace body 1 has an internal chamber for providing a vacuum reaction space. The air inlet assembly 2 is located on one side of the furnace body 1 and connected to the chamber, for connecting to an external gas source and introducing nitrogen into the chamber to create an oxygen-free environment. The exhaust assembly 3 is located on the other side of the furnace body 1 and connected to the chamber, for connecting to an external negative pressure device to extract gas from the furnace, thereby creating a vacuum environment.

[0033] Combination Figure 2As shown, the cooling assembly 4 includes a pneumatic valve 41, multiple sets of cooling pipes 42, and multiple support columns 43. The pneumatic valve 41 is located outside the furnace body 1 and is used to connect to an external cooling gas source (e.g., nitrogen). The multiple sets of cooling pipes 42 are connected to the pneumatic valve 41 and extend into the cavity of the furnace body 1, forming a cooling pipe network within the cavity of the furnace body 1. Figure 2 The grid-shaped support network 44 shown is arranged longitudinally within the chamber, and each set of cooling pipes 42 has multiple air vents 421. Multiple support columns 43 are provided on the remaining cooling pipes 42, except for the top cooling pipe 42, to support the panel 7. Multiple heating components 5 are disposed within the furnace body 1 and distributed below each set of cooling pipes 42.

[0034] Figure 2 and Figure 3 Six sets of cooling pipes 42 are exemplarily shown. The lower five sets of cooling pipes 42 are equipped with support columns 43 to support the heating and annealing of five panels 7 at a time. The upper cooling pipes 42 are not used to hold the panels 7, but rather to spray cryogenic nitrogen gas onto the panels 7 below them. Figure 1 It can be seen that multiple heating components 5 are arranged below each set of cooling pipes 42. Therefore, multiple heat sources are set on the upper and lower sides of each panel 7 to ensure temperature consistency during heating.

[0035] After the OLED panel enters the annealing process, panel 7 is placed on support column 43. Exhaust assembly 3 extracts air from the furnace until it approaches a near-ultimate vacuum. Then, intake assembly 2 introduces an appropriate amount of nitrogen to bring the pressure inside the furnace to a suitable range and further vent any remaining oxygen, creating an oxygen-free atmosphere. Heating assembly 5 then begins operation, reaching and maintaining the appropriate temperature according to different process requirements for a period of time. After heating, the cooling process begins. During cooling, cooling assembly 4 can be activated to spray low-temperature nitrogen gas onto panel 7 to cool it. During this process, exhaust assembly 3 continuously extracts gas until panel 7 returns to room temperature. Afterward, cooling assembly 4 stops supplying cooling gas, exhaust assembly 3 stops exhausting, and intake assembly 2 introduces nitrogen gas. Once the furnace pressure returns to normal, panel 7 is removed.

[0036] In this embodiment, the OLED panel vacuum annealing furnace has a cooling pipe 42 that is used to cool the panel 7 after heating and to provide a placement position for the panel 7. The cooling pipe 42 and the heating component 5 surround the panel 7 in a ring-like manner. Panel 7 is supported on support column 43. Multiple heating components 5 heat panel 7 from above and below. The large number of heating components 7 and this encircling heating method can improve the temperature consistency of panel 7 during heating. That is, when there is a temperature difference in different areas of the cavity, the temperature of the entire cavity can be made consistent by controlling the power of the heating components 5, thereby greatly improving the consistency of the product. Secondly, the cooling component 4 is not only used to support panel 7. After heating is completed and the cooling process begins, the cooling gas (such as nitrogen) flows out from the vent 421 to cool panel 7 from multiple directions, thus increasing the cooling speed and ensuring the temperature consistency during cooling, further improving the consistency of the product. Furthermore, the exhaust component 3 is activated at the same time as the cooling gas is introduced to extract the gas in the furnace, so as to prevent the solvent and water vapor volatilized from the substrate from remaining in the furnace and re-adhering to the surface of panel 7 during the cooling process, thereby reducing the defect rate.

[0037] exist Figure 4 In the embodiment shown, only downward-facing vent holes 421 are provided on the cooling pipe 42. Since the panel 7 is mounted above the cooling pipe 42 via the support column 43, upward-facing vent holes 421 can also be provided on the cooling pipe 42 to spray low-temperature nitrogen gas from both the top and bottom sides to cool the panel 7 from both sides, further preventing uneven temperature distribution of the panel 7 during the cooling process.

[0038] The cooling assembly 4 also includes a gas distribution block 45 connected between the cooling pipe 42 and the pneumatic valve 41. The gas distribution block 45 is located outside the furnace and has a main gas passage and a gas distribution passage inside, which correspond to the pneumatic valve 41 and the cooling pipe 42 respectively.

[0039] Intake component 2, such as Figure 9 As shown, the furnace includes a main intake pipe 21, multiple intake branch pipes 22 connected to the main intake pipe 21, and multiple intake connectors 23 on each intake branch pipe 22. The main intake pipe 21 is located outside the furnace and is used to connect to an external gas source. The intake connectors 23 are connected to the furnace body 1 and are used to input gas into the furnace. The design of multiple intake connectors 23 increases the number of air inlets inside the furnace and improves the consistency of the atmosphere inside the furnace.

[0040] Similarly, exhaust assembly 3, such as Figure 10 As shown, it includes an exhaust main pipe 31, multiple exhaust branch pipes 32 connected to the exhaust main pipe 31, and multiple exhaust connectors 33 provided on each exhaust branch pipe 32. The exhaust main pipe 31 is located outside the furnace and is used to connect to an external negative pressure device. The exhaust connectors 33 are connected to the furnace body 1 to extract the gas inside the furnace.

[0041] Preferably, in order to improve the heat preservation effect of the furnace body 1, an insulated inner liner 6 is provided inside the furnace. The insulated inner liner 6 is composed of multiple insulation boards spliced ​​together. The cooling pipe 42 passes through the insulation board and extends into the interior of the insulated inner liner 6. The support net 44 is formed inside the insulated inner liner 6.

[0042] In one embodiment, the heating component 5 is as follows: Figure 11 As shown, it includes a heating sleeve 51 and a heating wire 52 wrapped inside the heating sleeve 51. The two ends of the heating sleeve 52 are fixed to the inner wall of the furnace body 1. The heating wire 52 is connected to an external power source to heat the panel 7 supported on the support column 43.

[0043] Since different processes require different ambient temperatures, even under the same process temperature, there may be temperature differences at different locations on the same panel 7. Therefore, preferably, the furnace body is equipped with a temperature sensor (not shown in the figure), and each heating component 5 has a heating temperature (power). The temperature sensor is used to monitor whether there is a temperature difference in the furnace. When a temperature difference is detected in some locations, the power of the temperature sensor at the corresponding location is adjusted to eliminate the temperature difference and ensure the temperature consistency in the furnace.

[0044] The furnace body 1 is equipped with an openable front door 11, which is opened and closed by a cylinder. It opens when the panel 7 needs to be inserted or removed, and closes after entering the process. On the other side of the front door 11, the furnace body 1 is equipped with an openable back door 12, which is an inspection door. It is connected to the furnace body 1 by a hinge 13, and multiple locking blocks 14 are connected between the back door 12 and the furnace body 1. When closed, the locking blocks 14 are locked. To ensure airtightness, sealing rings (not shown) are provided at the front and back doors 11 and the back door 12.

[0045] Due to the high process temperature inside the furnace, even with the presence of an insulated inner liner 6, heat will still dissipate outwards through thermal radiation or conduction. Furthermore, excessively high furnace body 1 temperatures may cause the sealing rings at the front door 11 and rear door 12 to age, deform, or even fail, thereby disrupting the vacuum environment inside the furnace. To address this, multiple liquid-cooling pipes 15 are installed on the outer wall of the furnace body 1, each with an independent inlet 151 and outlet 152. By introducing coolant, a "thermal barrier" is formed on the surface of the furnace body 1. The flowing coolant carries away the remaining heat conducted out, preventing the furnace body 1 from overheating due to internal high temperatures, thus preventing burns to operators. It also prevents the furnace body 1 and sealing rings from deforming or being damaged due to prolonged heating, extending their service life. These liquid-cooling pipes 15 can be installed on the top, bottom, front door 11, and rear door 12 of the furnace body 1; this embodiment is not limited to these locations.

[0046] It will be apparent to those skilled in the art that this disclosure is not limited to the details of the exemplary embodiments described above, and that this disclosure can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of this disclosure is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this disclosure. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0047] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A vacuum annealing furnace for OLED panels, characterized in that, include: The furnace body has a hollow chamber inside; An air intake assembly is located on one side of the furnace body and connected to the chamber, used to connect to an external air source and introduce nitrogen into the chamber; An exhaust assembly, located on one side of the furnace body and connected to the chamber, is used to connect to an external negative pressure device and extract gas from the chamber. The cooling assembly includes a pneumatic valve, multiple sets of cooling pipes, and multiple support columns for supporting the OLED panel. The pneumatic valve is located outside the furnace body and is used to connect to an external cooling air source. The multiple sets of cooling pipes are connected to the pneumatic valve and extend into the chamber, and are arranged longitudinally in the chamber. The multiple support columns are distributed on the remaining cooling pipes except for the top cooling pipe. Each set of cooling pipes is provided with multiple air outlets. Multiple heating components are disposed inside the furnace body and distributed below each of the cooling pipes.

2. The OLED panel vacuum annealing furnace according to claim 1, characterized in that, Each set of cooling pipes forms a grid-shaped support network structure within the cavity.

3. The OLED panel vacuum annealing furnace according to claim 1, characterized in that, The cooling assembly also includes a gas distribution block disposed between the pneumatic valve and the cooling pipeline, the gas distribution block being disposed outside the furnace body.

4. The OLED panel vacuum annealing furnace according to claim 1, characterized in that, The exhaust assembly includes a main exhaust pipe, multiple exhaust branch pipes connected to the main exhaust pipe, and multiple exhaust connectors connected to the exhaust branch pipes. The main exhaust pipe is located outside the furnace body and is used to connect to an external negative pressure device. The exhaust connectors are connected to the furnace body.

5. The OLED panel vacuum annealing furnace according to claim 1, characterized in that, The air intake assembly includes a main air intake pipe, multiple air intake branch pipes connected to the main air intake pipe, and multiple air intake connectors connected to the air intake branch pipes. The main air intake pipe is located outside the furnace body and is used to connect to an external air source. The air intake connectors are connected to the furnace body.

6. The OLED panel vacuum annealing furnace according to claim 1, characterized in that, It also includes an insulated inner liner disposed within the furnace body, and the support column is disposed within the insulated inner liner.

7. The OLED panel vacuum annealing furnace according to claim 1, characterized in that, The heating temperature of the heating component is adjustable, and a temperature sensor is installed inside the furnace body, and / or The heating assembly includes a heating sleeve and a heating wire wrapped inside the heating sleeve.

8. The OLED panel vacuum annealing furnace according to claim 1, characterized in that, The furnace body is equipped with an openable front door, which is opened and closed by a cylinder.

9. The OLED panel vacuum annealing furnace according to claim 1, characterized in that, The furnace body is also provided with an openable back door, which is connected to the furnace body by a hinge, and multiple locking blocks are connected between the back door and the furnace body.

10. The vacuum annealing furnace for OLED panels according to claim 1, characterized in that, The outer wall of the furnace body is provided with multiple liquid cooling pipes, each of which has a liquid inlet and a liquid outlet.

Images