Thin film deposition method and device for organic light-emitting device
Through plasma excitation and spray deposition technology, the problems of poor film uniformity and slow deposition rate in traditional organic thin film deposition methods are solved, and the efficient deposition of organic thin films is achieved at low temperatures, improving the stability and production efficiency of the film.
Patent Information
- Application Number
- CN202411755007.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-02
- Publication Date
- 2025-02-18
AI Technical Summary
Traditional organic thin film deposition methods such as spin coating and coating have problems such as poor film uniformity and slow deposition rate.
A thin film deposition method is adopted, including selecting a suitable organic precursor material to form a precursor solution, generating plasma through a plasma excitation device, spraying the precursor solution with inert gas, forming an organic film through gas phase reaction, and physical adsorption Deposition on the substrate.
Film deposition at lower temperatures is achieved, which reduces the thermal stress and deformation of the substrate, accurately controls the film thickness and uniformity, and improves the deposition rate and film stability.
Smart Images
Figure CN119486552A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of organic electroluminescence, and in particular to a thin film deposition method and device for an organic electroluminescence device. Background Art
[0002] Organic electroluminescent devices are an important display technology, the core of which is organic thin films with high luminous efficiency and stability. Traditional organic thin film deposition methods such as spin coating and coating have problems such as poor film uniformity and slow deposition rate. Summary of the invention
[0003] The present invention provides a thin film deposition method and device for an organic electroluminescent device, which are used to solve the defects of poor film uniformity and slow deposition rate in conventional organic thin film deposition methods such as spin coating and coating in the prior art.
[0004] In one aspect, the present invention provides a thin film deposition method for an organic electroluminescent device, comprising: Step 1: According to the use requirements of the organic electroluminescent device, a suitable organic precursor material is selected, and the organic precursor material is dissolved in a solvent to form a precursor solution; Step 2: Evacuate the reaction chamber to a specified pressure and inject a certain amount of carrier gas into the reaction chamber; Step 3: generating plasma inside the reaction chamber by a plasma excitation device inside the reaction chamber; Step 4: spraying the precursor solution through a spray device to generate a precursor spray, and spraying an inert gas at the same time to mix the precursor spray with the inert gas to generate a gas phase mixture, and the gas phase mixture reacts with the plasma to generate an organic film; Step 5: placing the substrate in a reaction chamber, and depositing the organic film on the surface of the substrate by physical adsorption; Step 6: Detect the film deposition effect through a detection device; Step 7: Annealing the deposited film.
[0005] Preferably, the carrier gas includes: oxygen, nitrogen, argon and hydrogen.
[0006] Preferably, the allowable range of the working pressure of the reaction chamber after evacuation is 13.3 MPa-133 MPa.
[0007] On the other hand, the present invention also provides a thin film deposition device for an organic electroluminescent device, which is applied to the above-mentioned thin film deposition method for an organic electroluminescent device, including a reaction box, a placement seat fixedly connected to the bottom surface of the reaction box, a plurality of microwave emitters and a plurality of thermocouples are arranged on the inner side wall of the reaction box, a ventilation pipe 1 and a vacuum tube are arranged on the side wall of the reaction box, the air inlet of the ventilation pipe 1 is connected to the carrier gas source, the vacuum tube is connected to the vacuum pump, a spray box with an opening at the lower end is embedded in the top surface of the reaction box, a plurality of groups of spray components are arranged in the spray box, the spray components are connected to the precursor solution box and the inert gas source, and the precursor solution box stores the precursor solution.
[0008] Preferably, the spray assembly includes a sealing shield, which is fixedly connected to the top surface of the spray box, the sealing shield passes through the top surface of the spray box, an opening is provided at the lower end of the sealing shield, an air supply pipe and a spray pipe are inserted into the top end of the sealing shield, the air supply pipe is connected to the inert gas source, and the spray pipe is connected to the precursor solution tank.
[0009] Preferably, a control system is also included, and the control system includes: A control module for adjusting deposition parameters; The reaction monitoring module is used to monitor the reaction status of the deposition process in real time.
[0010] Preferably, the control module includes: A temperature control unit, used to control the working power of the thermocouple; A pressure control unit, used to control the working power of the vacuum pump; A first flow regulating unit, used for controlling the output flow of the inert gas; A second flow regulating unit, used to control the output flow of the precursor solution; The power regulating unit is used to control the working power of the microwave transmitter.
[0011] Preferably, the reaction monitoring module comprises: A data acquisition unit is used to collect monitoring parameters inside the reaction chamber, including: actual temperature and pressure inside the reaction chamber and actual voltage and current of the plasma excitation device; A parameter calculation unit, used for calculating reaction stability evaluation parameters; ; Wherein, S is the reaction stability evaluation parameter; is the thermal conductivity of the substrate material; is the density of the precursor solution; C is the specific heat capacity of the precursor solution; is the Boltzmann constant; T is the actual temperature inside the reaction chamber; is the dynamic viscosity of the precursor spray; d is the gas molecule diameter of the precursor spray; is the actual pressure inside the reaction chamber; M is the unit mole; is the Gibbs free energy of the molten state of the film material; is the solid-state Gibbs free energy of the thin film material; The actual gas flow rate for the precursor spray; is the actual voltage of the microwave transmitter; is the actual current of the microwave transmitter; The set value of the gas flow rate for the precursor spray; Set the operating power for the microwave transmitter; is the set standard pressure inside the reaction chamber; When the reaction stability evaluation parameter is less than a preset stability threshold, the reaction stability is judged to be poor and the deposition device needs to be repaired; otherwise, the reaction stability is judged to be good and the deposition device does not need to be repaired.
[0012] Compared with the prior art, the present invention has the following beneficial effects: The method is used to complete the deposition of thin films at a lower temperature, which can reduce the thermal stress and deformation of the substrate during the thin film deposition process. It is suitable for the deposition of thin films on temperature-sensitive substrate materials. The thin film deposition reaction is controlled by plasma to achieve precise control of the film thickness and uniformity. Compared with traditional organic thin film deposition methods, the method can effectively increase the deposition rate, is suitable for the deposition of thin films of various organic materials, is convenient for large-scale production, and annealing is performed on the deposited thin film to improve the stability of the film. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are 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.
[0014] Figure 1 It is a structural schematic diagram of the present invention.
[0015] Reference numerals: 1. Reaction box; 2. Placement seat; 3. Microwave transmitter; 4. Thermocouple; 5. Ventilation pipe 1; 6. Vacuum tube; 7. Vacuum pump; 8. Spray box; 9. Sealing shield; 10. Air supply pipe; 11. Spray tube. DETAILED DESCRIPTION
[0016] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are 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.
[0017] In addition, in the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes, and do not specifically refer to the order or sequence, nor are they used to limit the present invention. They are only used to distinguish components or operations described with the same technical terms, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions and technical features between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.
[0018] Example 1 An embodiment of the present invention provides a thin film deposition method for an organic electroluminescent device, comprising: Step 1: According to the use requirements of the organic electroluminescent device, a suitable organic precursor material is selected, and the organic precursor material is dissolved in a solvent to form a precursor solution; Step 2: Evacuate the reaction chamber to a specified pressure and inject a certain amount of carrier gas into the reaction chamber; Step 3: generating plasma inside the reaction chamber by a plasma excitation device inside the reaction chamber; Step 4: spraying the precursor solution through a spray device to generate a precursor spray, and spraying an inert gas at the same time to mix the precursor spray with the inert gas to generate a gas phase mixture, and the gas phase mixture reacts with the plasma to generate an organic film; Step 5: placing the substrate in a reaction chamber, and depositing the organic film on the surface of the substrate by physical adsorption; Step 6: Detect the film deposition effect through a detection device; Step 7: Annealing the deposited film.
[0019] Preferably, the carrier gas includes: oxygen, nitrogen, argon and hydrogen.
[0020] Preferably, the allowable range of the working pressure of the reaction chamber after evacuation is 13.3 MPa-133 MPa.
[0021] The beneficial effects of the above technical solution are: The method is used to complete the deposition of thin films at a lower temperature, which can reduce the thermal stress and deformation of the substrate during the thin film deposition process. It is suitable for the deposition of thin films on temperature-sensitive substrate materials. The thin film deposition reaction is controlled by plasma to achieve precise control of the film thickness and uniformity. Compared with traditional organic thin film deposition methods, the method can effectively increase the deposition rate, is suitable for the deposition of thin films of various organic materials, is convenient for large-scale production, and annealing is performed on the deposited thin film to improve the stability of the film.
[0022] Example 2 The present embodiment provides a thin film deposition device for an organic electroluminescent device, which is applied to a thin film deposition method for an organic electroluminescent device as described in Example 1, comprising a reaction box 1, a placement seat 2 is fixedly connected to the bottom surface of the reaction box 1, a plurality of microwave transmitters 3 and a plurality of thermocouples 4 are arranged on the inner side wall of the reaction box 1, a ventilation pipe 5 and a vacuum tube 6 are arranged on the side wall of the reaction box 1, the air inlet of the ventilation pipe 5 is connected to a carrier gas source, the vacuum tube 6 is connected to a vacuum pump 7, a spray box 8 with an opening at the lower end is embedded in the top surface of the reaction box 1, a plurality of groups of spray components are arranged in the spray box 8, the spray components are connected to a precursor solution box and an inert gas source, and the precursor solution box stores a precursor solution.
[0023] Preferably, the spray assembly includes a sealing shield 9, which is fixedly connected to the inner top surface of the spray box 8. The sealing shield 9 passes through the inner top surface of the spray box 8. An opening is provided at the lower end of the sealing shield 9. An air supply pipe 10 and a spray pipe 11 are inserted into the top of the sealing shield 9. The air supply pipe 10 is connected to the inert gas source, and the spray pipe 11 is connected to the precursor solution tank.
[0024] In this embodiment, the detection device is a spectroscopic ellipsometer.
[0025] The beneficial effects of the above technical solution are: By setting up a placement seat 2, the substrate is placed on the placement seat 2, which facilitates the accurate placement of the substrate. Through the dual temperature control means of the thermocouple 4 and the power of the microwave transmitter 3, the auxiliary control of the temperature can be completed by the thermocouple 4 under the premise that the microwave transmitter 3 adjusts the plasma density appropriately, thereby realizing accurate control of the plasma density and temperature.
[0026] The provision of the sealing shield 9 ensures that the inert gas and the precursor spray are quickly and evenly mixed after being sprayed, thereby ensuring the uniformity of the gas phase mixture.
[0027] Example 3 On the basis of embodiment 2, a control system is also included, and the control system includes: A control module for adjusting deposition parameters; The reaction monitoring module is used to monitor the reaction status of the deposition process in real time.
[0028] Preferably, the control module includes: A temperature control unit, used to control the working power of the thermocouple 4; A pressure regulating unit, used to control the working power of the vacuum pump 7; A first flow regulating unit, used for controlling the output flow of the inert gas; A second flow regulating unit, used to control the output flow of the precursor solution; The power regulating unit is used to control the working power of the microwave transmitter 3.
[0029] Preferably, the reaction monitoring module comprises: A data acquisition unit is used to collect monitoring parameters inside the reaction chamber, including: actual temperature and pressure inside the reaction chamber and actual voltage and current of the plasma excitation device; A parameter calculation unit, used for calculating reaction stability evaluation parameters; ; Wherein, S is the reaction stability evaluation parameter; is the thermal conductivity of the substrate material; is the density of the precursor solution; C is the specific heat capacity of the precursor solution; is the Boltzmann constant; T is the actual temperature inside the reaction chamber; is the dynamic viscosity of the precursor spray; d is the gas molecule diameter of the precursor spray; is the actual pressure inside the reaction chamber; M is the unit mole; is the Gibbs free energy of the molten state of the film material; is the solid-state Gibbs free energy of the thin film material; The actual gas flow rate for the precursor spray; is the actual voltage of the microwave transmitter 3; is the actual current of the microwave transmitter 3; The set value of the gas flow rate for the precursor spray; is the set working power of the microwave transmitter 3; is the set standard pressure inside the reaction chamber; When the reaction stability evaluation parameter is less than a preset stability threshold, the reaction stability is judged to be poor and the deposition device needs to be repaired; otherwise, the reaction stability is judged to be good and the deposition device does not need to be repaired.
[0030] In this embodiment, the deposition parameters include: the temperature of the reaction chamber, the pressure of the reaction chamber, the gas flow rate of the inert gas, the spraying flow rate of the precursor solution, and the power of the microwave transmitter (3).
[0031] In this embodiment, the Gibbs free energy of the molten state of the thin film material and the Gibbs free energy of the solid state of the thin film material are obtained by looking up a table.
[0032] The beneficial effects of the above technical solution are: By adjusting the temperature of the reaction chamber, the pressure of the reaction chamber, the gas flow rate of the inert gas, the spray flow rate of the precursor solution and the power of the microwave emitter 3, independent adjustment of each deposition parameter is achieved, so that the deposition parameters can be adjusted accordingly for different organic materials and different deposition thicknesses, thereby achieving precise control of the film thickness and film uniformity.
[0033] By real-time monitoring of monitoring parameters and calculation of reaction stability evaluation parameters, the reaction stability can be evaluated, thereby ensuring the film deposition effect and avoiding the degradation of film quality caused by the instability of the deposition reaction. By setting the reaction stability evaluation parameters, it is possible to automatically judge whether the film deposition reaction is stable, and then realize automatic monitoring of the reaction stability state, and automatically stop the reaction when the reaction is unstable, avoiding waste of deposition materials and substrates.
[0034] Example 4 On the basis of Example 1, it also includes: Step 8: Select a substrate after deposition at random time intervals as an evaluation sample for sampling inspection; Step 9: Calculate the quality assessment parameters of the evaluation sample; ; ; Where U is the quality assessment parameter; are the calculation weighting coefficients for film thickness, film uniformity, stoichiometric ratio, and defect density, respectively; It is the preset maximum allowable deviation ratio of film thickness; is the theoretical film deposition thickness; is the actual average film thickness; It is the preset maximum allowable deviation ratio of film uniformity; is the maximum thickness of the film; is the molar mass of the film; is the mass of the deposited film; is the molar mass of the precursor spray; is the loss mass of the precursor spray; B is the theoretical molar ratio; is the preset maximum allowable value of defect density; Z is the number of defects that can be observed; A is the area of the substrate deposition area; is the actual gas flow rate of the precursor spray; t is the deposition time; k is the surface chemical reaction shorthand constant, in units of ; d is the diameter of the gas molecule of the precursor spray; is the actual pressure inside the reaction chamber; is the dynamic viscosity of the precursor spray; When the quality evaluation parameter is lower than a preset evaluation threshold, it is judged that the film deposition quality is poor and the deposition device needs to be repaired; otherwise, it is judged that the film deposition quality is good and the deposition device does not need to be repaired.
[0035] In this embodiment, the theoretical molar ratio is calculated based on the stoichiometric equation.
[0036] The beneficial effects of the above technical solution are: By taking out an evaluation sample at random time intervals for sampling and testing, the actual film deposition quality is evaluated and the judgment of the actual film deposition quality is determined, thereby ensuring the stability of the film deposition quality.
[0037] The film deposition quality is evaluated through four aspects: film thickness, film uniformity, stoichiometric ratio and defect density, which ensures the comprehensiveness of the evaluation results. When any aspect of the deposition quality is deficient, it can be reflected in the quality evaluation results, which improves the accuracy and comprehensiveness of the evaluation results. By comprehensively considering the four aspects of the film deposition quality, when the quality in one aspect is qualified but the overall quality is low, the decline in deposition quality can be discovered in advance, so that timely maintenance and adjustment can be carried out to avoid the occurrence of defective products.
[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A thin film deposition method for an organic electroluminescent device, characterized in that: include: Step 1: According to the use requirements of the organic electroluminescent device, a suitable organic precursor material is selected, and the organic precursor material is dissolved in a solvent to form a precursor solution; Step 2: Evacuate the reaction chamber to a specified pressure and inject a certain amount of carrier gas into the reaction chamber; Step 3: generating plasma inside the reaction chamber by a plasma excitation device inside the reaction chamber; Step 4: spraying the precursor solution through a spray device to generate a precursor spray, and spraying an inert gas at the same time to mix the precursor spray with the inert gas to generate a gas phase mixture, and the gas phase mixture reacts with the plasma to generate an organic film; Step 5: placing the substrate in a reaction chamber, and depositing the organic film on the surface of the substrate by physical adsorption; Step 6: Detect the film deposition effect through a detection device; Step 7: Annealing the deposited film.
2. The thin film deposition method of an organic electroluminescent device according to claim 1, characterized in that: Carrier gases include: oxygen, nitrogen, argon and hydrogen.
3. The thin film deposition method for an organic electroluminescent device according to claim 1, characterized in that: The allowable range of working pressure after the reaction chamber is evacuated is 13.3MPa-133MPa.
4. A thin film deposition device for an organic electroluminescent device, applied to a thin film deposition method for an organic electroluminescent device as claimed in any one of claims 1 to 3, characterized in that: The invention comprises a reaction box (1), wherein a placement seat (2) is fixedly connected to the bottom surface of the reaction box (1), a plurality of microwave emitters (3) and a plurality of thermocouples (4) are arranged on the inner side wall of the reaction box (1), a ventilation pipe (5) and a vacuum tube (6) are arranged on the side wall of the reaction box (1), the air inlet of the ventilation pipe (5) is connected to a carrier gas source, the vacuum tube (6) is connected to a vacuum pump (7), a spray box (8) with an opening at the bottom is embedded in the top surface of the reaction box (1), a plurality of spray components are arranged in the spray box (8), the spray components are connected to a precursor solution box and an inert gas source, and a precursor solution is stored in the precursor solution box.
5. The thin film deposition device for an organic electroluminescent device according to claim 4, characterized in that: The spray assembly comprises a sealing shield (9), which is fixedly connected to the inner top surface of the spray box (8), the sealing shield (9) penetrates the inner top surface of the spray box (8), the lower end of the sealing shield (9) is provided with an opening, the top end of the sealing shield (9) is inserted with an air supply pipe (10) and a spray pipe (11), the air supply pipe (10) is connected to an inert gas source, and the spray pipe (11) is connected to a precursor solution tank.
6. The thin film deposition device for an organic electroluminescent device according to claim 4, characterized in that: It also includes a control system, which includes: A control module for adjusting deposition parameters; The reaction monitoring module is used to monitor the reaction status of the deposition process in real time.
7. The thin film deposition device for an organic electroluminescent device according to claim 6, characterized in that: The control module includes: A temperature control unit, used for controlling the working power of the thermocouple (4); A pressure regulating unit, used for controlling the working power of the vacuum pump (7); A first flow regulating unit, used for controlling the output flow of the inert gas; A second flow regulating unit, used to control the output flow of the precursor solution; The power regulating unit is used to control the working power of the microwave transmitter (3).
8. The thin film deposition device for an organic electroluminescent device according to claim 6, characterized in that: The reaction monitoring module includes: A data acquisition unit is used to collect monitoring parameters inside the reaction chamber, including: actual temperature and pressure inside the reaction chamber and actual voltage and current of the plasma excitation device; A parameter calculation unit, used for calculating reaction stability evaluation parameters; ; Wherein, S is the reaction stability evaluation parameter; is the thermal conductivity of the substrate material; is the density of the precursor solution; C is the specific heat capacity of the precursor solution; is the Boltzmann constant; T is the actual temperature inside the reaction chamber; is the dynamic viscosity of the precursor spray; d is the gas molecule diameter of the precursor spray; is the actual pressure inside the reaction chamber; M is the unit mole; is the Gibbs free energy of the molten state of the film material; is the solid-state Gibbs free energy of the thin film material; The actual gas flow rate for the precursor spray; is the actual voltage of the microwave transmitter (3); is the actual current of the microwave transmitter (3); The set value of the gas flow rate for the precursor spray; is the set working power of the microwave transmitter (3); is the set standard pressure inside the reaction chamber; When the reaction stability evaluation parameter is less than a preset stability threshold, the reaction stability is judged to be poor and the deposition device needs to be repaired. Otherwise, the reaction stability is judged to be good and the deposition device does not need to be repaired.