Vacuum film forming device and film forming method

Abstract

The invention discloses a vacuum film forming device and a film forming method.The device comprises a vacuum cavity, the vacuum cavity is connected with an air suction pipeline, an air inlet pipeline and a pressure relief pipeline, the end, away from the vacuum cavity, of the air suction pipeline is connected with a vacuum pump, the air suction pipeline is provided with a proportional valve, and the pressure relief pipeline is provided with a pressure relief valve. The end, away from the vacuum cavity, of the gas inlet pipeline is connected with an inert gas source, the inert gas source can convey inert gas into the vacuum cavity, a gas inlet adjusting valve is arranged on the gas inlet pipeline, and the end, away from the vacuum cavity, of the pressure relief pipeline is connected with a pressure relief gas source. And the pressure relief gas source can convey pressure relief gas into the vacuum cavity. The inert gas is introduced to enable the pressure position in the vacuum cavity to be at the initial film forming pressure for a period of time, the number of adopted vacuum pumps is small, the use cost is low, and the occupied space is small.

Description

Technical Field

[0001] The present invention relates to the field of vacuum film forming technology, and in particular to a vacuum film forming device and a film forming method. Background Art

[0002] Vacuum crystal making is to place a substrate coated with a wet film in a chamber and use vacuum equipment to evacuate the chamber, thereby removing the moisture in the wet film, while the solid matter can be fixed on the substrate.

[0003] In the process of vacuum film formation, from normal pressure (1×10 5 It takes a while from the initial pressure of film formation to the actual film forming pressure (temporarily called the invalid time), and the effective time from the initial pressure of film formation to the final pressure of film formation (temporarily called the effective working time). The key to film formation is to form the film as quickly as possible within the expected effective working time (the actual time for different solutions is different).

[0004] Existing vacuum film forming equipment basically adopts: 1. Vacuum system: including vacuum pump group (mechanical pump, Roots pump, dry pump, molecular pump, plug valve and stop valve, etc.); 2. Vacuum chamber: including chamber, upper cover and observation window. The working process is: turn on multiple sets of vacuum pumps - turn on molecular pumps - place the coated substrate into the vacuum chamber - open the valve between the vacuum pump and the chamber - then open the valve between the molecular pump and the vacuum chamber - pump to the limit vacuum and then close the valve between the molecular pump and the vacuum chamber - chamber pressure relief - take out the substrate.

[0005] The above-mentioned existing vacuum film-forming equipment can only simply evacuate until it reaches the ultimate vacuum. It is impossible to maintain the pressure at the film-forming starting pressure for a certain period of time and then continue to evacuate to the ultimate vacuum, because only relying on the vacuum pump or other pump body structure, once the pipeline valve corresponding to the vacuum pump is closed, the pressure in the cavity will change more or less, so that the pressure in the cavity cannot be at the film-forming starting pressure. If the film-forming starting pressure cannot be guaranteed, the effective working time cannot be established. Of course, for the above-mentioned prior art, even if the film-forming starting pressure cannot be maintained for a period of time, as long as it uses a large number of high-power vacuum pumps, it can still shorten the overall film-forming working time (that is, both the ineffective time and the effective working time will be shortened). However, in order to effectively extract the water from the solution, the equipment needs to use a pump body with a larger pumping speed, such as a mechanical pump group, a dry pump, and a molecular pump, and even needs to add an additional vacuum tank body, which not only increases the floor space of the equipment, but also greatly increases the cost of the equipment.

[0006] Therefore, the art is in urgent need of a new vacuum film-forming device and film-forming method to solve the above problems. Summary of the invention

[0007] The object of the present invention is to provide a vacuum film forming device and a film forming method to solve the problems existing in the above-mentioned prior art, adopt a smaller number of pump bodies to achieve crystal film forming, reduce the use cost and manufacturing cost, and occupy a smaller area.

[0008] To achieve the above object, the present invention provides the following solutions: The present invention discloses a vacuum film-forming device, comprising a vacuum chamber, wherein the vacuum chamber is connected with an exhaust pipeline, an air intake pipeline and a pressure relief pipeline, wherein one end of the exhaust pipeline away from the vacuum chamber is connected with a vacuum pump, a proportional valve is provided on the exhaust pipeline, one end of the air intake pipeline away from the vacuum chamber is connected with an inert gas source, and the inert gas source can transport inert gas into the vacuum chamber, an air intake regulating valve is provided on the air intake pipeline, and one end of the pressure relief pipeline away from the vacuum chamber is connected with a pressure relief gas source, and the pressure relief gas source can transport pressure relief gas into the vacuum chamber.

[0009] Preferably, a pipeline valve is provided on the air extraction pipeline, and the pipeline valve is closer to the vacuum pump than the proportional valve.

[0010] Preferably, the vacuum pumps are provided in plurality. When the vacuum pumps are provided in two or more, the plurality of vacuum pumps are arranged in parallel.

[0011] Preferably, a pressure relief valve is provided on the pressure relief pipeline.

[0012] Preferably, the inert gas source is a nitrogen tank.

[0013] Preferably, the pressure relief gas source is an air compression bottle or a nitrogen tank.

[0014] Preferably, a vacuum gauge is provided in the vacuum chamber.

[0015] Preferably, the air intake regulating valve is an internal thread micro-regulating valve.

[0016] The present invention discloses a film forming method of a vacuum film forming device, comprising the following steps: S1, turn on the vacuum pump; S2, opening the vacuum chamber, placing the substrate to be film-formed after the wet film is coated, and closing the vacuum chamber; S3. Set the internal pressure value of the vacuum chamber as required, open the pipeline valve, and adjust the internal pressure of the vacuum chamber by adjusting the air inlet regulating valve and the proportional valve; S4, closing the air inlet regulating valve and fully opening the proportional valve, thereby completing the substrate film forming process; S5. Close the proportional valve and open the pressure relief valve to allow the vacuum chamber to reach normal pressure and remove the substrate.

[0017] Compared with the prior art, the present invention has achieved the following technical effects: The present invention also fills the vacuum chamber with inert gas during the evacuation process, so that the pressure in the vacuum chamber can be accurately maintained at the film-forming starting pressure for a period of time, and the inert gas injected can also carry out the moisture in the wet film, so as to achieve the use of a small number of vacuum pumps to quickly form the wet film on the substrate within the expected effective working time. The key point of the perovskite solution crystallization film is that the wet film needs to be crystallized quickly from the wet film to the dry film, so as to ensure the key nucleation quality of the perovskite film, such as the grain growth direction and grain size. Finally, the whole equipment has a simple structure, low manufacturing cost, small footprint, and good practicality and applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a structural schematic diagram of a vacuum film forming device in Example 1; In the figure: 1-vacuum chamber; 2-exhaust pipeline; 3-vacuum pump; 4-intake pipeline; 5-intake regulating valve; 6-pressure relief pipeline; 7-pressure relief valve; 8-vacuum gauge; 9-proportional valve; 10-pipeline valve. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] The object of the present invention is to provide a vacuum film forming device and a film forming method to solve the problems existing in the above-mentioned prior art, adopt a smaller number of pump bodies to achieve crystal film forming, reduce the use cost and manufacturing cost, and occupy a smaller area.

[0022] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] Embodiment 1 like Figure 1As shown, this embodiment provides a vacuum film forming device, including a vacuum chamber 1, which is a closed chamber with a switch door and an observation window on its side. The vacuum chamber 1 is connected to an exhaust pipeline 2, an air intake pipeline 4 and a pressure relief pipeline 6. The end of the exhaust pipeline 2 away from the vacuum chamber 1 is connected to a vacuum pump 3, which is used to extract the gas in the vacuum chamber 1, and a proportional valve 9 is provided on the exhaust pipeline 2, which is used to adjust the exhaust rate. The end of the air intake pipeline 4 away from the vacuum chamber 1 is connected to an inert gas source, which can transport inert gas into the vacuum chamber 1, and the air intake pipeline 4 is provided with an air intake regulating valve 5, which is used to adjust the intake rate of the inert gas. The end of the pressure relief pipeline 6 away from the vacuum chamber 1 is connected to a pressure relief gas source, which can transport pressure relief gas into the vacuum chamber 1, and the air pressure in the vacuum chamber 1 is restored to normal pressure after the pressure relief gas source is input.

[0024] In actual use, first put the substrate coated with a wet film into the vacuum chamber 1, close the switch door of the vacuum chamber 1, and make the interior of the vacuum chamber 1 in a sealed state. Start the vacuum pump 3 to evacuate the vacuum chamber 1, so that the pressure in the vacuum chamber 1 gradually decreases until it is less than the initial pressure of film formation (for example, when the initial pressure of film formation is 100Pa, it can be evacuated to 1Pa at this time), then open the air intake regulating valve 5 and adjust the opening size of the proportional valve 9 and the air intake regulating valve 5 so that the air intake rate is the same as the air outlet rate, thereby maintaining the pressure in the vacuum chamber 1 at 1Pa, and remember the scale value of the air intake regulating valve 5 at this time. Then, adjust the opening of the air intake regulating valve 5 again so that the air intake rate is greater than the air extraction rate, so the air pressure in the vacuum chamber 1 gradually increases until it reaches 100Pa (i.e., the initial pressure of film formation), and then quickly adjust the air intake regulating valve 5 to the scale position just recorded, so that the internal pressure of the vacuum chamber 1 can be maintained at this value. Then close the air inlet regulating valve 5, so that the substrate formally enters the film forming process, and under the carrying effect of the inert gas and the exhaust effect of the vacuum pump 3, the wet film can remove moisture within the effective working time to complete the film forming process. Finally, use the pressure relief pipeline 6 to input pressure relief gas into the vacuum chamber 1 until the air pressure in the vacuum chamber 1 returns to the normal pressure state, and then open the switch door and take out the substrate.

[0025] In this embodiment, a pipeline valve 10 is provided on the exhaust pipeline 2 . The pipeline valve 10 is closer to the vacuum pump 3 than the proportional valve 9 . The pipeline valve 10 is used to control the gas flow on the exhaust pipeline 2 .

[0026] In this embodiment, the vacuum pump 3 is provided with a plurality of Figure 1There is one vacuum pump 3 in the apparatus. As the area of ​​the substrate gradually increases, the demand for negative pressure will also increase, so the number of vacuum pumps 3 will also increase. When there are two or more vacuum pumps 3, and several vacuum pumps 3 are arranged in parallel, that is, one pipeline valve 10 can control the opening or closing of all vacuum pumps 3.

[0027] In this embodiment, a pressure relief valve 7 is provided on the pressure relief pipeline 6 , and the pressure relief valve 7 is used to control the flow of the pressure relief pipeline 6 .

[0028] In this embodiment, the inert gas source is a nitrogen tank, so the inert gas is nitrogen. The reason for using inert gas is that it has stable chemical properties and is not prone to chemical reactions, thereby being able to maintain a stable gas pressure.

[0029] During the vacuuming process, an appropriate proportion of inert gas is introduced through the air inlet regulating valve 5, which can make the wet film on the substrate realize nucleation crystallization more quickly. And according to the process requirements, different wet film coatings can use different pumping speeds by adjusting the proportional valve 9, and different pressures of the stable vacuum chamber 1 can obtain a more suitable film-forming effect.

[0030] In this embodiment, the pressure relief gas source is an air compression bottle or a nitrogen tank, so the pressure relief gas is air or nitrogen, which is selected according to the actual usage cost of the user.

[0031] In this embodiment, a vacuum gauge 8 is provided in the vacuum chamber 1 , and the vacuum gauge 8 can be used to monitor the pressure in the vacuum chamber 1 in real time.

[0032] In this embodiment, the air inlet regulating valve 5 adopts the existing internal thread micro regulating valve, which can finely adjust the flow rate. Specifically, the straight-through ferrule diameter of the internal thread micro regulating valve is 10mm, the outer diameter of the cannula is 10mm, and high-purity nitrogen is passed through the tube at a pressure of 0.2±0.05MPa.

[0033] Embodiment 2 This embodiment provides a film forming method of a vacuum film forming device, based on the vacuum film forming device disclosed in the first embodiment, comprising the following steps: S1. Turn on the vacuum pump 3. It should be noted that the pipeline valve 10 is not turned on at this time. It is only to preheat the vacuum pump 3 so that it can reach the working state as soon as possible.

[0034] S2, opening the vacuum chamber 1, placing the substrate to be film-formed after being coated with the wet film, and closing the vacuum chamber 1.

[0035] S3. Set the internal pressure value of the vacuum chamber 1 as required, open the pipeline valve 10, and adjust the internal pressure of the vacuum chamber 1 by adjusting the air intake regulating valve 5 and the proportional valve 9. The specific process is: first start the vacuum pump 3 to evacuate the vacuum chamber 1, so that the pressure in the vacuum chamber 1 gradually decreases until it is less than the initial pressure of film formation (for example, when the initial pressure of film formation is 100Pa, it can be evacuated to 1Pa at this time). Then open the air intake regulating valve 5 and adjust the opening size of the proportional valve 9 and the air intake regulating valve 5 so that the air intake rate is the same as the air outlet rate, thereby maintaining the pressure in the vacuum chamber 1 at 1Pa, and remember the scale value of the air intake regulating valve 5 at this time. Then, adjust the opening of the air intake regulating valve 5 again so that the air intake rate is greater than the air extraction rate, so the air pressure in the vacuum chamber 1 gradually increases until it reaches 100Pa (i.e., the initial pressure of film formation). At this time, quickly adjust the air intake regulating valve 5 to the scale position just recorded again, so that the internal pressure of the vacuum chamber 1 can be maintained at this value.

[0036] S4, close the air inlet regulating valve 5 and fully open the proportional valve 9, so that the pressure in the vacuum chamber 1 drops from the initial film forming pressure to the final film forming pressure, thereby completing the substrate film forming process.

[0037] S5, close the proportional valve 9 and open the pressure relief valve 7, so that the vacuum chamber 1 reaches normal pressure and the substrate is taken out.

[0038] In this embodiment, the vacuum gauge 8 of the vacuum chamber 1 can display the pressure value in the vacuum chamber 1 in real time. Different pressure and holding time technical solutions can be adopted according to the wet film coatings of different components, as follows: When the wet film uses a high boiling point solution (i.e., a solution with a high boiling point solvent such as DMF, NMP, DMSO, etc. having a boiling point higher than 150° C.), the pressure in step S3 is 1000±100 Pa, which is maintained for 10 seconds before closing the air inlet regulating valve 5 and continuing to evacuate.

[0039] When the wet film uses a low boiling point solution (i.e., a solution of a low boiling point solvent such as DME, ACE, THF, etc. with a temperature below 70° C.), the pressure in step S3 is 300±50 Pa, which is maintained for 10 seconds before closing the air inlet regulating valve 5 and continuing to evacuate.

[0040] If it is a wet film coating made of special solution, the air inlet regulating valve 5 and the proportional valve 9 can be used for precise control to adjust the appropriate process pressure, keep constant pressure for 10 seconds, then close the air inlet and continue to evacuate.

[0041] This example also provides four groups of control experiments, which are as follows: Comparative case a: Conditions: 120 mm × 120 mm substrate, using low boiling point solution.

[0042] In conventional vacuum film-forming equipment, it takes 4 seconds for one vacuum pump and 3 evacuations to change the color of the wet film (color change means film formation is completed), and it takes 2 seconds for three vacuum pumps and 3 evacuations to change the color of the wet film.

[0043] The vacuum film forming device provided in this embodiment only needs one vacuum pump 3 and an inert gas to control the pressure of the vacuum chamber 1 for 2 seconds to achieve the color change of the wet film.

[0044] Therefore, the low boiling point solution experiment of the vacuum film forming device provided in this embodiment uses one vacuum pump 3, which can achieve the same effect as that of a conventional vacuum film forming device using three vacuum pumps 3.

[0045] Comparative case b: Conditions: 120 mm × 120 mm substrate, using high boiling point solution.

[0046] In conventional vacuum film-forming equipment, one vacuum pump and three evacuations cannot achieve wet film color change, and three vacuum pumps and three vacuum pumps need 5 seconds to achieve wet film color change.

[0047] The vacuum film forming device provided in this embodiment only needs one vacuum pump 3 and inert gas to control the pressure of the vacuum chamber 1 for 4 seconds to achieve the color change of the wet film.

[0048] Therefore, the high boiling point solution experiment of the vacuum film-forming device provided in this embodiment uses one vacuum pump 3, which can achieve the same effect as that of a conventional vacuum film-forming device using three vacuum pumps 3.

[0049] Comparative case c: Conditions: 600mm×600mm substrate, using high boiling point solution.

[0050] Conventional vacuum film-forming equipment with 4 vacuum pumps and 3 evacuations cannot achieve wet film discoloration.

[0051] The vacuum film forming device provided in this embodiment only needs two vacuum pumps 3 and inert gas to control the pressure of the vacuum chamber 1 for 15 seconds to achieve the color change of the wet film.

[0052] Therefore, the high boiling point solution experiment of the vacuum film-forming device provided in this embodiment uses two vacuum pumps 3, which is better than the four vacuum pumps 3 of the conventional vacuum film-forming equipment, and can complete tasks that the conventional vacuum film-forming equipment cannot complete.

[0053] Comparative case d: Conditions: 1200mm×600mm substrate, using high boiling point solution.

[0054] Conventional vacuum film-forming equipment with 12 vacuum pumps and 3 evacuations cannot achieve uniform color change of the wet film.

[0055] The vacuum film-forming device provided in this embodiment only needs to use four vacuum pumps 3 and pass inert gas to control the pressure of the vacuum chamber 1 for 17 seconds to achieve uniform color change of the wet film.

[0056] Therefore, the high boiling point solution experiment of the vacuum film forming device provided in this embodiment uses four vacuum pumps 3, which is better than the effect of 12 vacuum pumps 3 of the conventional vacuum film forming equipment.

[0057] The present invention has the following advantages in actual use: 1. Greatly reduce the manufacturing cost of equipment, and achieve uniform film formation of high boiling point formula that conventional equipment cannot complete.

[0058] 2. Reduce the floor space of the equipment: For every two vacuum pumps added to the equipment, the floor space needs to be increased by 1 square meter.

[0059] 3. Greatly reduce the energy consumption of the equipment; for every two vacuum pumps used less, the equipment power is reduced by 6 kilowatts.

[0060] 4. Shorten the process time.

[0061] 5. Improve the quality of film formation; by formulating the process curve of the film formation process in combination with the solution formula coated on the substrate, the present invention can easily realize the precise control of the pressure of the vacuum chamber 1 of the equipment to improve the quality of film formation and ensure the consistency of crystal nucleus growth.

[0062] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A vacuum film forming device, characterized in that: The invention comprises a vacuum chamber, wherein the vacuum chamber is connected with an exhaust pipeline, an air intake pipeline and a pressure relief pipeline, wherein one end of the exhaust pipeline away from the vacuum chamber is connected with a vacuum pump, a proportional valve is arranged on the exhaust pipeline, one end of the air intake pipeline away from the vacuum chamber is connected with an inert gas source, and the inert gas source can transport inert gas into the vacuum chamber, an air intake regulating valve is arranged on the air intake pipeline, and one end of the pressure relief pipeline away from the vacuum chamber is connected with a pressure relief gas source, and the pressure relief gas source can transport pressure relief gas into the vacuum chamber.

2. The vacuum film forming device according to claim 1, characterized in that: The air extraction pipeline is provided with a pipeline valve, and the pipeline valve is closer to the vacuum pump than the proportional valve.

3. The vacuum film forming device according to claim 1, characterized in that: There are several vacuum pumps. When there are two or more vacuum pumps, the several vacuum pumps are arranged in parallel.

4. The vacuum film forming device according to claim 1, characterized in that: The pressure relief pipeline is provided with a pressure relief valve.

5. The vacuum film forming device according to claim 1, characterized in that: The inert gas source is a nitrogen tank.

6. The vacuum film forming device according to claim 1, characterized in that: The pressure relief gas source is an air compression bottle or a nitrogen tank.

7. The vacuum film forming device according to claim 1, characterized in that: A vacuum gauge is arranged in the vacuum chamber.

8. The vacuum film forming device according to claim 1, characterized in that: The air intake regulating valve is an internal thread micro regulating valve.

9. A film forming method using a vacuum film forming device, characterized in that: The vacuum film forming device according to any one of claims 1 to 8 comprises the following steps: S1, turn on the vacuum pump; S2, opening the vacuum chamber, placing the substrate to be film-formed after the wet film is coated, and closing the vacuum chamber; S3. Set the internal pressure value of the vacuum chamber as required, open the pipeline valve, and adjust the internal pressure of the vacuum chamber by adjusting the air inlet regulating valve and the proportional valve; S4, closing the air inlet regulating valve and fully opening the proportional valve, thereby completing the substrate film forming process; S5. Close the proportional valve and open the pressure relief valve to allow the vacuum chamber to reach normal pressure and remove the substrate.

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