Micro-doped multi-source evaporation device and method

Abstract

The invention discloses a trace doping multi-source evaporation device and a trace doping multi-source evaporation method. The multi-source evaporation device comprises an evaporation bin which is provided with a hollow inner cavity capable of being closed; the evaporation disc is arranged in the hollow inner cavity and is used for placing a substrate; the evaporation container is arranged in the hollow inner cavity, is positioned below the evaporation disc, and is used for containing a main body material and evaporating the main body material onto the substrate; the evaporation table is arranged in the hollow inner cavity, is positioned below the evaporation disc, is positioned on one side of the evaporation container, and is used for gasifying the powdery doping material; the powder feeding mechanism is arranged in the hollow inner cavity and located above the evaporation table so as to supply powdery doping materials to the evaporation table according to the preset speed. According to the multi-source evaporation device, the supply amount of a doping material is controlled through the powder feeding mechanism, a very small amount of powder falls onto the evaporation table at a time, the material is gasified instantly, the evaporation speed of the doping material is adjusted by controlling the feeding speed, and finally the doping uniformity of a thin film is guaranteed while micro doping is achieved.

Description

Technical Field

[0001] The invention relates to a trace-doped multi-source evaporation device and also to a corresponding multi-source evaporation method, belonging to the technical field of evaporation doping. Background Art

[0002] Evaporation refers to a process in which a certain heating evaporation method is used to evaporate the coating material under vacuum conditions to vaporize it, and then the vapor of the coating material is condensed on the surface of the substrate to form a coating.

[0003] During the evaporation process, if other elements need to be doped, there are two main methods. The first method is to pre-mix the evaporation material with the doping material, and then evenly disperse them by ball milling or other methods. During evaporation, the mixed raw materials are placed under a single heat source for evaporation. This method is simple to operate and the structure of the evaporation equipment is not complicated, but the doping ratio is difficult to control accurately because the melting points, boiling points and vapor pressures of different materials are different, resulting in inconsistent vaporization rates, which ultimately affects the doping ratio in the film. The second evaporation method is to place the evaporation main material and the doping material in different evaporation crucibles, and use dual or multiple heat sources to independently control the evaporation process. This method can adjust the doping amount more accurately and has good doping uniformity, so it has become the mainstream evaporation scheme. However, when the doping amount is very small, such as at the ppm or ppb level, it becomes difficult to control the doping amount using an evaporation crucible for thermal evaporation. This is because the amount of doping raw material added to the crucible is small, it is difficult to form a stable surface, and the raw material changes greatly during the evaporation process. At the same time, there are problems such as uneven heating and high sensitivity of the evaporation rate to temperature and pressure.

[0004] In summary, although evaporation doping technology has made progress in precisely controlling doping amounts and uniformity, it still faces some challenges, especially when dealing with extremely small doping amounts. These challenges include the stability of raw materials, heating uniformity, and sensitivity to environmental conditions during the evaporation process. Solving these problems requires further optimization of the evaporation process and equipment design. Summary of the invention

[0005] The primary technical problem to be solved by the present invention is to provide a trace-doped multi-source evaporation device.

[0006] Another technical problem to be solved by the present invention is to provide a trace-doped multi-source evaporation method.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] According to a first aspect of an embodiment of the present invention, there is provided a trace-doped multi-source evaporation device, comprising:

[0009] A vapor deposition chamber having a closable hollow inner cavity;

[0010] An evaporation plate, disposed in the hollow inner cavity, for placing a substrate;

[0011] An evaporation container, disposed in the hollow inner cavity and below the evaporation plate, for containing the main body material;

[0012] An evaporation table, disposed in the hollow inner cavity and below the evaporation plate, and the evaporation table is located on one side of the evaporation container, and is used to vaporize the powdered doping material;

[0013] The powder feeding mechanism is arranged in the hollow inner cavity and located above the evaporation table to supply powdered doping material to the evaporation table at a preset rate.

[0014] Preferably, the preset rate of the powder feeding mechanism is adjustable to adjust the uniformity of doping within a preset adjustment range.

[0015] Preferably, there are multiple evaporation containers, each of which contains a different type of main body material;

[0016] There are a plurality of evaporation tables, each of which corresponds to one of the powder feeding mechanisms, and each of the powder feeding mechanisms supplies different types of doping materials to the corresponding evaporation table at a respective preset rate.

[0017] Preferably, the evaporation container further comprises:

[0018] A clamp pot, disposed in the hollow inner cavity and below the vapor deposition plate;

[0019] A heating part, in contact with the crucible, for heating the crucible;

[0020] The sealing cover is rotatably or flippably mounted on the top of the tongs pot and is used to open or close the top opening of the tongs pot.

[0021] Preferably, the evaporation disk is installed in the hollow inner cavity so as to be rotatable at a uniform speed around a preset direction, so as to drive the substrate to rotate at a uniform speed around the preset direction; wherein the preset direction is perpendicular to the surface of the evaporation disk.

[0022] Preferably, the multi-source evaporation device further comprises:

[0023] A vacuum machine is connected to the evaporation chamber and is used to evacuate the hollow inner cavity to a predetermined vacuum.

[0024] Preferably, the evaporation plate is provided with a plurality of vacuum adsorption holes, and the vacuum adsorption holes are connected to the vacuum machine so as to adsorb the substrate onto the surface of the evaporation plate by vacuum adsorption.

[0025] According to a second aspect of an embodiment of the present invention, a trace-doped multi-source evaporation method is provided, comprising the following steps:

[0026] placing the substrate on a vapor deposition plate;

[0027] Weighing a first mass of the main material and placing it into a vapor deposition container;

[0028] Weighing a second mass of powdered doping material and placing it into the powder feeding mechanism;

[0029] The evaporation chamber is evacuated to a predetermined vacuum, and the evaporation container and the evaporation table are heated;

[0030] Opening the evaporation container to evaporate the main material onto the substrate; and opening the powder feeding mechanism to supply the powdered doping material onto the evaporation table at a preset rate;

[0031] When a preset time or a preset film thickness is reached, closing the evaporation container and the powder feeding mechanism;

[0032] Stop for a preset time until the evaporated film cools down to room temperature.

[0033] Preferably, after the powder feeding mechanism is turned on, the powder feeding mechanism is controlled to supply a preset rate of powdered doping material so as to adjust the uniformity of doping within a preset adjustment range.

[0034] According to a third aspect of an embodiment of the present invention, there is provided a trace-doped multi-source evaporation method, comprising the following steps:

[0035] placing the substrate on a vapor deposition plate;

[0036] Weighing a variety of main materials and placing them into different evaporation containers respectively;

[0037] Weighing a variety of powdered doping materials and placing them into different powder feeding mechanisms;

[0038] The evaporation chamber is evacuated to a predetermined vacuum, and a plurality of evaporation containers and a plurality of evaporation tables are heated;

[0039] Opening each of the evaporation containers respectively to evaporate different main materials onto the substrate respectively; and opening each of the powder feeding mechanisms respectively to supply powdered doping materials onto the corresponding evaporation tables at a preset rate respectively;

[0040] When the preset time or the preset film thickness is reached, all evaporation containers and all powder feeding mechanisms are closed;

[0041] Stop for a preset time until the evaporated film cools down to room temperature.

[0042] Compared with the prior art, the present invention has the following technical effects:

[0043] (1) One or more of the original multi-source doping evaporation crucibles are replaced with a high-temperature evaporation table, and the supply amount of the doping material is controlled in conjunction with the powder feeding mechanism, so that a very small amount of powder can be instantly vaporized at a time, thereby adjusting the evaporation speed of the doping material by controlling the feeding rate rather than the temperature. This not only achieves trace doping, but also ensures the uniformity of thin film doping.

[0044] (2) The structure is simple and only minor modifications are required to the traditional evaporation device, which facilitates the conversion of the production line.

[0045] (3) It is possible to evaporate a variety of main materials through multiple evaporation containers, and to evaporate a variety of doping materials by cooperating with multiple evaporation tables and powder feeding mechanisms, providing the possibility of flexibly adjusting different thin film evaporation schemes.

[0046] (4) The powder feeding mechanism can accurately control the supply amount of doping materials, effectively avoiding material waste and improving the efficiency and economy of the evaporation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 A schematic structural diagram of a trace-doped multi-source evaporation device provided in the first embodiment of the present invention;

[0048] Figure 2 A schematic structural diagram of another trace-doped multi-source evaporation device provided in the first embodiment of the present invention;

[0049] Figure 3 A flow chart of a trace-doped multi-source evaporation method provided in accordance with a second embodiment of the present invention;

[0050] Figure 4 This is a flow chart of a trace-doped multi-source evaporation method provided in accordance with the third embodiment of the present invention. DETAILED DESCRIPTION

[0051] The technical content of the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0052] The core concept of the embodiment of the present invention is: on the basis of traditional multi-source evaporation, a trace powder feeding mechanism and an ultra-high temperature evaporation table are used for doping, and an independent evaporation container is used to replace the traditional doping crucible evaporation technical solution. Through the mechanical structure of the trace feeding, a very small amount of powder falls on the high temperature platform at a time, and the material is instantly vaporized, so that the evaporation speed of the doping material is adjusted by controlling the feeding rate, so that the trace amount of doping material powder falls on the high temperature evaporation table at a preset rate over time, so as to achieve the purpose of controlling trace doping.

[0053] First embodiment

[0054] like Figure 1 As shown, a trace-doped multi-source evaporation device provided by the first embodiment of the present invention includes an evaporation chamber 1, an evaporation plate 2, an evaporation container 3, an evaporation table 4 and a powder feeding mechanism 5. The evaporation chamber 1 has a closable hollow inner cavity 101. The evaporation plate 2 is arranged in the hollow inner cavity 101 for placing a substrate. The evaporation container 3 is arranged in the hollow inner cavity 101 and is located below the evaporation plate 2, and is used to contain the main material and evaporate the main material onto the substrate. The evaporation table 4 is arranged in the hollow inner cavity 101 and is located below the evaporation plate 2, and the evaporation table 4 is located on one side of the evaporation container 3, and is used to vaporize the powdered doping material. The powder feeding mechanism 5 is arranged in the hollow inner cavity 101 and is located above the evaporation table 4 to supply the powdered doping material to the evaporation table 4 at a preset rate.

[0055] Specifically, in this embodiment, the evaporation chamber 1 is a hollow shell made of metal material, which is used to form a closed evaporation space, and the evaporation plate 2, the evaporation container 3, the evaporation table 4 and the powder feeding mechanism 5 can all be arranged in the evaporation space. In addition, the evaporation chamber 1 is also connected to the vacuum machine 6, and the vacuum machine 6 can evacuate the hollow inner cavity 101 of the evaporation chamber 1 to a predetermined vacuum, so as to perform vacuum evaporation under a predetermined vacuum environment to ensure the quality of the coating.

[0056] In this embodiment, the evaporation plate 2 is installed in the hollow inner cavity 101 so as to be able to rotate at a uniform speed around a preset direction, so as to drive the substrate to rotate at a uniform speed around a preset direction. The preset direction is perpendicular to the surface of the evaporation plate 2. Thus, the evaporation plate 2 that rotates at a uniform speed drives the substrate to rotate at a uniform speed, thereby ensuring the uniformity of material evaporation during the evaporation process.

[0057] In addition, preferably, the evaporation plate 2 is provided with a plurality of vacuum adsorption holes 21, which are connected to the vacuum machine 6 to adsorb the substrate on the surface of the evaporation plate 2 by vacuum adsorption. Therefore, when the substrate needs to be removed, the suction force can be directly removed, which is not only convenient for taking and placing, but also does not cause damage to the surface of the substrate, which is conducive to ensuring the quality of the coating.

[0058] In this embodiment, the evaporation container 3 includes a crucible 31, a heating part 32 and a cover 33. Among them, the crucible 31 is arranged in the hollow inner cavity 101 and is located below the evaporation plate 2, and is used to contain the main material. The heating part 32 is in contact with the crucible 31, and is used to heat the crucible 31. In this embodiment, the heating part 32 is a heating wire arranged around the outside of the crucible 31, and can also be replaced by other forms of heating structures in other embodiments. The cover 33 is rotatably mounted on the top of the crucible 31 to open or close the top opening 311 of the crucible. It can be understood that in another embodiment, the cover 33 can also be mounted on the top of the crucible 31 in a flipping manner to open or close the top opening 311 of the crucible. During specific use, the main material is first added into the crucible 31, and then the top opening 311 of the crucible is closed by the cover 33, and then the crucible 31 is heated by the heating part 32 to vaporize the main material, and finally, the top opening 311 of the crucible is opened so that the vaporized main material can be evaporated on the substrate to realize the evaporation process of the main material.

[0059] In this embodiment, the evaporation table 4 is a high-temperature truncated table (not limited to a circular shape). When the powdered doping material is dropped onto the evaporation table 4, it will be instantly vaporized under the action of high temperature, thereby cooperating with the main material to achieve multi-source evaporation of trace doping.

[0060] In this embodiment, the powder feeding mechanism 5 can adopt a powder feeding structure driven by micro-airflow or electrostatic drive, or a feeding structure through a vibration platform, or a mechanical screw propulsion structure, etc., and can be adaptively selected according to needs. In addition, in this embodiment, the preset rate of the powder feeding mechanism 5 is adjustable, so that the supply amount of the powdered doping material can be accurately adjusted within the preset adjustment range during the evaporation process to achieve the control of trace doping.

[0061] like Figure 2 As shown, in another embodiment, preferably, there are multiple evaporation containers 3, and each evaporation container 3 contains different types of main materials. Correspondingly, there are multiple evaporation tables 4, and each evaporation table 4 corresponds to a powder feeding mechanism 5, and each powder feeding mechanism 5 supplies different types of doping materials to the corresponding evaporation table 4 according to its own preset rate. In this way, mixed multi-source evaporation of multiple main materials and multiple doping materials can be achieved, and the specific number of main materials and doping materials can be selected according to needs to meet different coating requirements.

[0062] Second embodiment

[0063] like Figure 3 As shown, based on the above first embodiment, the second embodiment of the present invention provides a trace-doped multi-source evaporation method, which specifically includes steps S1 to S7:

[0064] S1: Place the substrate on the vapor deposition plate 2.

[0065] In this embodiment, the substrate is disposed on the vapor deposition plate 2 by vacuum adsorption. In other embodiments, the substrate may also be disposed by other methods (eg, snap connection).

[0066] S2: weighing a first mass of the main material and placing it into the evaporation container 3 .

[0067] After the substrate is set, it is necessary to weigh the first mass of the evaporated main body material, for example, weigh 1000 g; then, put the weighed main body material into the clamp pot 31 .

[0068] S3: weighing a second mass of powdered doping material and placing it into the powder feeding mechanism 5 .

[0069] Specifically, after the weighing of the main material is completed, it is necessary to continue to weigh the second mass of the powdered doping material, for example, weigh 100 mg; then, grind it sufficiently with a planetary ball mill, weigh it again, and put it into the powder feeding mechanism 5.

[0070] S4: evacuating the evaporation chamber 1 to a predetermined vacuum, and heating the evaporation container 3 and the evaporation stage 4.

[0071] Specifically, after the main material and the doping material are placed, the evaporation chamber 1 needs to be evacuated to a predetermined vacuum by the vacuum machine 6. Then, the evaporation container 3 and the evaporation table 4 are heated under the predetermined vacuum environment to vaporize the main material in the clamp pot 31, and the evaporation table 4 is heated to a specific temperature so that the powdered doping material can be instantly vaporized after being dropped on the evaporation table 4.

[0072] S5: Open the evaporation container to evaporate the main material onto the substrate; and open the powder feeding mechanism 5 to supply the powdered doping material onto the evaporation table at a preset rate.

[0073] Specifically, after the crucible 31 is heated for a period of time, the cover 33 is opened so that the vaporized main material in the crucible 31 can be evaporated onto the substrate. At the same time, the powder feeding mechanism 5 is turned on to supply the powdered doping material to the evaporation table 4 at a preset rate, so that the vaporized doping material can also be evaporated onto the substrate, thereby cooperating with the main material to achieve multi-source evaporation of trace doping.

[0074] In addition, in this embodiment, after the powder feeding mechanism 5 is turned on, the powder feeding mechanism 5 is controlled to supply a preset rate of powdered doping material to perform doping adjustment within a preset adjustment range, thereby ultimately achieving micro-doping while ensuring uniformity of thin film doping.

[0075] S6: When the preset time length or the preset film thickness is reached, the evaporation container 3 and the powder feeding mechanism 5 are closed.

[0076] S7: Pause for a preset time until the evaporated film cools down to room temperature.

[0077] Third embodiment:

[0078] like Figure 4 As shown, based on the above first embodiment, the third embodiment of the present invention provides another trace-doping multi-source evaporation method, which specifically includes steps S10 to S70:

[0079] S10: placing the substrate on the vapor deposition plate 2 .

[0080] In this embodiment, the substrate is disposed on the vapor deposition plate 2 by vacuum adsorption. In other embodiments, the substrate may also be disposed by other methods (eg, snap connection).

[0081] S20: Weighing a plurality of main body materials and placing them into different evaporation containers 3 respectively.

[0082] In this embodiment, a plurality of evaporation containers 3 are arranged in the hollow inner cavity 101 of the evaporation chamber 1. After the substrate is set, it is necessary to weigh a plurality of main materials respectively, and the specific mass of each main material can be adjusted as needed. Then, the plurality of main materials are placed in different evaporation containers 3 respectively.

[0083] S30: Weighing a plurality of powdered doping materials and placing them into different powder feeding mechanisms 5 .

[0084] Specifically, after the weighing of the main material is completed, it is necessary to continue to weigh a plurality of powdered doping materials. In this embodiment, there are a plurality of evaporation tables 4, and each evaporation table 4 corresponds to a powder feeding mechanism 5, so that after the plurality of powdered doping materials are weighed respectively, they are placed in the corresponding powder feeding mechanism 5.

[0085] S40: evacuating the evaporation chamber 1 to a predetermined vacuum, and heating the plurality of evaporation containers 3 and the plurality of evaporation stages 4.

[0086] Specifically, after the main material and the doping material are placed, the evaporation chamber 1 needs to be evacuated to a predetermined vacuum by the vacuum machine 6. Then, each evaporation container 3 and each evaporation table 4 are heated under the predetermined vacuum environment to vaporize the main material in each clamp pot 31, and each evaporation table 4 is heated to a specific temperature, so that different powdered doping materials can be instantly vaporized after being dropped on different evaporation tables 4.

[0087] S50: opening each evaporation container respectively to evaporate different main materials onto the substrate respectively; and opening each powder feeding mechanism respectively to supply powdered doping materials onto corresponding evaporation tables at a preset rate respectively.

[0088] Specifically, after heating each of the crucibles 31 for a period of time, the cover 33 of each crucible 31 is opened, so that the vaporized main material in each crucible 31 can be evaporated onto the substrate. At the same time, each powder feeding mechanism 5 is turned on to supply powdered doping materials to each evaporation table 4 at a preset rate, so that the vaporized multiple doping materials can also be evaporated onto the substrate, thereby cooperating with the main material to achieve multi-source evaporation of trace doping.

[0089] In addition, in this embodiment, after each powder feeding mechanism 5 is turned on, the preset rate at which each powder feeding mechanism 5 supplies powdered doping material can be controlled to perform doping adjustment within a preset adjustment range, thereby ultimately achieving micro-doping while ensuring the uniformity of thin film doping.

[0090] S60: When the preset time or the preset film thickness is reached, all evaporation containers and all powder feeding mechanisms are closed.

[0091] S70: Pause for a preset time until the evaporated film cools down to room temperature.

[0092] In summary, the embodiment of the present invention provides a trace-doped multi-source evaporation device and method, which has the following technical effects:

[0093] (1) One or more of the original multi-source doping evaporation crucibles are replaced with a high-temperature evaporation table, and the supply amount of the doping material is controlled in conjunction with the powder feeding mechanism, so that a very small amount of powder can be instantly vaporized at a time, thereby adjusting the evaporation speed of the doping material by controlling the feeding rate rather than the temperature. This not only achieves trace doping, but also ensures the uniformity of thin film doping.

[0094] (2) The structure is simple and only minor modifications are required to the traditional evaporation device, which facilitates the conversion of the production line.

[0095] (3) It is possible to evaporate a variety of main materials through multiple evaporation containers, and to evaporate a variety of doping materials by cooperating with multiple evaporation tables and powder feeding mechanisms, providing the possibility of flexibly adjusting different thin film evaporation schemes.

[0096] (4) The powder feeding mechanism can accurately control the supply amount of doping materials, effectively avoiding material waste and improving the efficiency and economy of the evaporation process.

[0097] It should be noted that the above embodiments are only examples, and the technical solutions of the various embodiments can be combined, all within the protection scope of the present invention.

[0098] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0099] The above is a detailed description of the trace doping multi-source evaporation device and method provided by the present invention. For those skilled in the art, any obvious changes made to it without departing from the essence of the present invention will constitute an infringement of the patent right of the present invention and will bear corresponding legal responsibilities.

Claims

1. A trace-doped multi-source evaporation device, characterized in that include: A vapor deposition chamber having a closable hollow inner cavity; An evaporation plate, disposed in the hollow inner cavity, for placing a substrate; An evaporation container, disposed in the hollow inner cavity and below the evaporation plate, for containing the main body material; An evaporation table, disposed in the hollow inner cavity and below the evaporation plate, and the evaporation table is located on one side of the evaporation container, and is used to vaporize the powdered doping material; The powder feeding mechanism is arranged in the hollow inner cavity and located above the evaporation table to supply powdered doping material to the evaporation table at a preset rate.

2. The multi-source evaporation device according to claim 1, wherein: The preset rate of the powder feeding mechanism is adjustable to adjust the uniformity of doping within a preset adjustment range.

3. The multi-source evaporation device according to claim 1, characterized in that: There are multiple evaporation containers, each of which contains a different type of main body material; There are a plurality of evaporation tables, each of which corresponds to one of the powder feeding mechanisms, and each of the powder feeding mechanisms supplies different types of doping materials to the corresponding evaporation table at a respective preset rate.

4. The multi-source evaporation device according to claim 1, characterized in that The evaporation container comprises: A clamp pot, disposed in the hollow inner cavity and below the vapor deposition plate; A heating part, in contact with the crucible, for heating the crucible; The sealing cover is rotatably or flippably mounted on the top of the tongs pot and is used to open or close the top opening of the tongs pot.

5. The multi-source evaporation device according to claim 1, wherein: The evaporation plate is installed in the hollow inner cavity so as to be rotatable at a uniform speed around a preset direction, so as to drive the substrate to rotate at a uniform speed around the preset direction; wherein the preset direction is perpendicular to the surface of the evaporation plate.

6. The multi-source evaporation device according to claim 1, characterized in that Also includes: A vacuum machine is connected to the evaporation chamber and is used to evacuate the hollow inner cavity to a predetermined vacuum.

7. The multi-source evaporation device according to claim 6, characterized in that: The evaporation plate is provided with a plurality of vacuum adsorption holes, and the vacuum adsorption holes are connected to the vacuum machine so as to adsorb the substrate on the surface of the evaporation plate by vacuum adsorption.

8. A trace doping multi-source evaporation method, characterized in that The steps include: placing the substrate on a vapor deposition plate; Weighing a first mass of the main material and placing it into a vapor deposition container; Weighing a second mass of powdered doping material and placing it into the powder feeding mechanism; The evaporation chamber is evacuated to a predetermined vacuum, and the evaporation container and the evaporation table are heated; Opening the evaporation container to evaporate the main material onto the substrate; and opening the powder feeding mechanism to supply the powdered doping material onto the evaporation table at a preset rate; When a preset time or a preset film thickness is reached, closing the evaporation container and the powder feeding mechanism; Stop for a preset time until the evaporated film cools down to room temperature.

9. The multi-source evaporation method according to claim 8, wherein: When the powder feeding mechanism is turned on, the powder feeding mechanism is controlled to supply a preset rate of powdered doping material so as to adjust the uniformity of doping within a preset adjustment range.

10. A trace doping multi-source evaporation method, characterized in that The steps include: placing the substrate on a vapor deposition plate; Weighing a variety of main materials and placing them into different evaporation containers respectively; Weighing a variety of powdered doping materials and placing them into different powder feeding mechanisms; The evaporation chamber is evacuated to a predetermined vacuum, and a plurality of evaporation containers and a plurality of evaporation tables are heated; Opening each of the evaporation containers respectively to evaporate different main materials onto the substrate respectively; and opening each of the powder feeding mechanisms respectively to supply powdered doping materials onto the corresponding evaporation tables at a preset rate respectively; When the preset time or the preset film thickness is reached, all evaporation containers and all powder feeding mechanisms are closed; Stop for a preset time until the evaporated film cools down to room temperature.

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