Film evaporation method and equipment for multi-component complex compound

Abstract

The invention discloses a thin film evaporation method and equipment for a multi-component complex compound. The method comprises the following steps: preparing required compound powder based on chemical components of a thin film to be evaporated; mixing the compound powder according to a preset molar ratio to obtain mixture powder; adding the mixture powder into an evaporation container, and sealing the evaporation container; the substrate is placed on an evaporation plate; the evaporation container is heated to a first preset temperature through a temperature control device and lasts for a first preset duration, so that the mixture powder is fully melted and reacted; raising the temperature of the evaporation container to a second preset temperature through a temperature control device, and opening the evaporation container to start evaporation; continuously evaporating until a second preset duration or a preset film thickness is reached, and then closing the temperature control device; and cooling to normal temperature to obtain the evaporation film. According to the method, the thin film can be prepared through simple single-furnace evaporation, so that the steps of the process are reduced, and the energy consumption is reduced.

Description

Technical Field

[0001] The invention relates to a thin film evaporation method for a multi-component complex compound and also relates to corresponding thin film evaporation equipment, belonging to the technical field of thin film evaporation. Background Art

[0002] Physical vapor deposition (PVD) and chemical vapor deposition (CVD) are two common coating technologies. PVD technology is usually carried out in a vacuum environment. It converts the material source (such as solid or liquid) into gaseous atoms or molecules by physical methods, and then uses low-pressure gas or plasma to deposit these gaseous atoms or molecules on the surface of the substrate. CVD technology vaporizes the reactants and deposits them directly on the substrate through chemical reactions to form substances different from the reactants.

[0003] Scintillators are an important class of detector materials, widely used in fields such as nuclear physics, medical imaging and astronomy. Since the discovery in 1896 that cadmium tungstate can emit light signals under radiation excitation, the research on scintillator materials has been continuously developing. Among them, thallium-doped cesium iodide (CsI:Tl) is a typical scintillator material, which has been widely used in medical detectors due to its high scintillation efficiency, needle-like film structure and good optical properties.

[0004] In recent years, perovskite scintillator materials have also received widespread attention. For example, CsCu2I3 and Cs3Cu2I5 are favored for their excellent photoluminescence quantum yield (PLQY) and low afterglow characteristics. These materials are usually prepared into film layers by dual-source, multi-source evaporation or spin coating. Another scintillator material that has attracted much attention is Cs5Cu3Cl6I2, which easily forms a needle-shaped film after evaporation. This structure helps to reduce scattering and improve spatial resolution.

[0005] However, due to the multi-element structure of Cs5Cu3Cl6I2, it is difficult to ensure the proportion of each component directly through multi-source evaporation. At present, the common preparation method in the prior art is to first use the Bridgman method to prepare Cs5Cu3Cl6I2 single crystals, then grind the single crystals into powder, and then prepare the film by thermal evaporation. Although this method can ensure the proportion of the evaporation components, the process is time-consuming and requires a lot of energy to maintain the high temperature in the furnace for a long time. Summary of the invention

[0006] The primary technical problem to be solved by the present invention is to provide a thin film evaporation method for multi-component complex compounds.

[0007] Another technical problem to be solved by the present invention is to provide a thin film evaporation device for multi-component complex compounds.

[0008] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0009] According to a first aspect of an embodiment of the present invention, a thin film evaporation method of a multi-component complex compound is provided, comprising the following steps:

[0010] Based on the chemical composition of the film to be evaporated, the required compound powder is prepared;

[0011] Mixing the compound powders according to a preset molar ratio to obtain a mixture powder;

[0012] Adding the mixed powder into a vapor deposition container and sealing the vapor deposition container;

[0013] Placing the substrate on a vapor deposition plate; wherein the vapor deposition plate is located directly above the vapor deposition container;

[0014] The evaporation container is heated to a first preset temperature by a temperature control device and is kept for a first preset time so that the mixture powder can fully melt and react; wherein the first preset temperature is between the melting point and the boiling point of the mixture powder;

[0015] When the mixed powder is continuously heated at the first preset temperature for the first preset time, the temperature of the evaporation container is raised to a second preset temperature by the temperature control device, and the evaporation container is opened to start evaporation; wherein the second preset temperature is greater than the boiling point of the mixed powder;

[0016] Continue evaporation until a second preset time or a preset film thickness is reached, and then turn off the temperature control device;

[0017] The film was cooled to room temperature to obtain a vapor-deposited film.

[0018] Preferably, the thin film to be evaporated corresponds to a plurality of configuration combinations, each of the configuration combinations includes a plurality of compounds, and the molar ratio of each compound in each of the configuration combinations is different.

[0019] Preferably, the film to be evaporated is a Cs5Cu3Cl6I2 film, the plurality of compounds include CsCl, CuCl and CuI, and the molar ratio of CsCl, CuCl and CuI is 5:1:2.

[0020] Preferably, the film to be evaporated is a Cs5Cu3Cl6I2 film, the plurality of compounds include CsI, CsCl and CuCl, and the molar ratio of CsI, CsCl and CuCl is 2:3:3.

[0021] Preferably, the first preset temperature is 380-420° C., and the first preset time is not less than 2 hours.

[0022] Preferably, the second preset temperature is not less than 600° C., and the second preset time is proportional to the mass of the mixture powder.

[0023] Preferably, the mixed powder is added into a vapor deposition container, specifically comprising:

[0024] Under the protection of inert gas, the mixture powder is fully ground using a planetary ball mill to obtain a finely ground mixture powder;

[0025] The ground mixture powder is weighed to add a preset mass of the mixture powder into the evaporation container.

[0026] Preferably, after the first preset temperature and the second preset temperature are set, the values ​​remain unchanged during the entire evaporation process.

[0027] According to a second aspect of an embodiment of the present invention, there is provided a thin film evaporation device for a multi-component complex compound, comprising:

[0028] A vapor deposition chamber having a closable hollow inner cavity;

[0029] An evaporation plate is disposed in the hollow inner cavity for placing a substrate;

[0030] An evaporation container is disposed in the hollow inner cavity and below the evaporation plate to contain the mixture powder;

[0031] A temperature control device, disposed in the hollow inner cavity and in contact with the evaporation container, for controlling the heating temperature and heating time of the evaporation container according to the chemical composition of the mixed powder;

[0032] The temperature control device is used to heat the evaporation container to a first preset temperature and keep it for a first preset time so that the mixture powder can fully melt and react; wherein the first preset temperature is between the melting point and boiling point of the mixture powder;

[0033] The temperature control device is also used to heat the evaporation container to a second preset temperature and continue for a second preset time until the evaporation is completed; wherein the second preset temperature is greater than the boiling point of the mixed powder.

[0034] Preferably, the thin film evaporation equipment further comprises:

[0035] A vacuum machine is connected to the evaporation chamber and is used to evacuate the hollow inner cavity to a predetermined vacuum.

[0036] Compared with the prior art, the present invention successfully prepares Cs5Cu3Cl6I2 thin film by a simplified single furnace evaporation method, which not only omits the traditional Bridgman single crystal preparation process, but also reduces the process steps and required equipment, reduces energy consumption, and improves the utilization rate of raw materials. In addition, this thin film evaporation method is simple to operate and has a wide range of applicability. It can be used for other materials that can react in a molten or partially solution state, thereby significantly improving production efficiency and the scope of application of materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A schematic diagram of a thin film evaporation method of a multi-component complex compound provided in the first embodiment of the present invention;

[0038] Figure 2 A structural diagram of a thin film evaporation device for multi-component complex compounds provided in accordance with the second embodiment of the present invention. DETAILED DESCRIPTION

[0039] The technical content of the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0040] The embodiment of the present invention provides a thin film evaporation method of a multi-component complex compound, which adopts a one-step method, bypasses the traditional Bridgman single crystal preparation process, and directly mixes the required compound powders according to a certain molar ratio to form a mixture powder. In addition, a temperature control device is introduced in the evaporation process to control the temperature of the mixture powder above the melting point and below the boiling point, so that the fusion and chemical reaction of each raw material are completed at a low temperature in the evaporation container. After the reaction is complete, the temperature is raised in molecular form to above the boiling point to complete the evaporation, and finally a thin film is formed on the substrate.

[0041] The following only takes Cs5Cu3Cl6I2 thin film as an example for explanation, but the thin film material is not necessarily Cs5Cu3Cl6I2 thin film. Other materials that need to react in a molten or partially solution state and then form a film by thermal evaporation can be evaporated using the method of the embodiment of the present invention.

[0042] First embodiment

[0043] like Figure 1 As shown, a thin film evaporation method of a multi-component complex compound provided by the first embodiment of the present invention specifically includes steps S1 to S8:

[0044] S1: Based on the chemical composition of the film to be evaporated, the required compound powder is prepared.

[0045] The chemical composition of the film to be evaporated needs to satisfy the requirement that it can be generated by melting reaction of multiple compounds at a certain temperature. It can be seen that the film to be evaporated can correspond to multiple configuration combinations, each of which includes multiple compounds, and the molar ratio of each compound in each configuration combination is different.

[0046] S2: Mixing the required compound powders according to a preset molar ratio to obtain a mixture powder.

[0047] Specifically, in this embodiment, the film to be evaporated is a Cs5Cu3Cl6I2 film, the multiple compounds include CsCl, CuCl and CuI, and the molar ratio of CsCl, CuCl and CuI is 5:1:2. In addition, for the Cs5Cu3Cl6I2 film, the multiple compounds can also be CsI, CsCl and CuCl, and the molar ratio of CsI, CsCl and CuCl is 2:3:3.

[0048] S3: Add the mixed powder into a vapor deposition container and seal the vapor deposition container.

[0049] Specifically, it includes steps S31 to S32:

[0050] S31: fully grinding the mixture powder using a planetary ball mill under the protection of an inert gas to obtain a finely ground mixture powder;

[0051] S32: Weighing the ground mixture powder to add a preset mass of the mixture powder into the evaporation container.

[0052] S4: placing the substrate on the evaporation plate.

[0053] The evaporation plate is located directly above the evaporation container, and preferably, the evaporation plate can rotate at a constant speed around its central axis, thereby ensuring the uniformity of the coating.

[0054] S5: heating the evaporation container to a first preset temperature by a temperature control device and heating the temperature for a first preset time so that the mixed powder can fully melt and react.

[0055] In this embodiment, after the mixed powder is added into the evaporation container, the temperature of the evaporation container is slowly raised to 380-420° C., preferably 400° C., by a temperature control device and maintained for two hours so that the mixed powder can fully melt and react.

[0056] It is understandable that 380-420° C. is between the melting point and boiling point of the mixture powder, so that the mixture powder can be in a molten state and will not be vaporized. However, if the composition of the mixture powder changes, the first preset temperature will also change accordingly.

[0057] S6: The temperature of the evaporation container is raised to a second preset temperature by the temperature control device, and the evaporation container is opened to start evaporation.

[0058] Specifically, after the mixed powder in step S5 is continuously heated at 400°C for two hours, the temperature of the evaporation container is raised to 600°C by the temperature control device. At this time, since 600°C is greater than the boiling point of the mixed powder, the Cs5Cu3Cl6I2 generated after the melting reaction is vaporized. Then, the evaporation container is opened to allow the vaporized Cs5Cu3Cl6I2 to evaporate upward, thereby being vapor-deposited on the substrate directly above.

[0059] S7: Continue evaporation until a second preset time or a preset film thickness is reached, and then turn off the temperature control device.

[0060] When evaporation begins, the temperature of the evaporation container is maintained at 600° C. by a temperature control device until the raw material is consumed or the preset film thickness is reached, and then the temperature control device is turned off to stop evaporation.

[0061] It can be understood that the second preset time is proportional to the mass of the mixed powder. The more mixed powder there is in the evaporation container, the longer the second preset time is, and vice versa. The preset film thickness can be set as needed, for example: the film thickness is 1μm to 2mm. When this thickness is reached, the temperature control device is turned off and the evaporation is stopped.

[0062] S8: Cooling to room temperature to obtain a vapor-deposited film.

[0063] Second embodiment

[0064] like Figure 2 As shown, on the basis of the above-mentioned first embodiment, the second embodiment of the present invention provides a thin film evaporation device for multi-component complex compounds, including an evaporation chamber 1, an evaporation plate 2, an evaporation container 3 and a temperature control device 4. Among them, 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 for containing the mixture powder. The temperature control device 4 is arranged in the hollow inner cavity 101 and is in contact with the evaporation container 3, so as to control the heating temperature and heating time of the evaporation container according to the chemical composition of the mixture powder.

[0065] 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 and the temperature control device 4 can be arranged in the evaporation space. In addition, the evaporation chamber 1 is also connected to a vacuum machine 5, and the vacuum machine 5 can be used to 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.

[0066] 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.

[0067] In addition, preferably, the evaporation plate 2 is provided with a plurality of vacuum adsorption holes 21, which are connected to the vacuum machine 5 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.

[0068] In this embodiment, the evaporation container 3 includes a crucible 31, a heating portion 32 and a cover 33. The crucible 31 is arranged in the hollow inner cavity 101 and is located below the evaporation plate 2 for containing the mixture powder. The heating portion 32 is in contact with the crucible 31 for heating the crucible 31. In this embodiment, the heating portion 32 is a heating wire arranged around the outside of the crucible 31, and can 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 mixture powder 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 mixture powder, and finally, the top opening 311 of the crucible is opened so that the vaporized mixture powder can be evaporated on the substrate to realize the evaporation process of the mixture powder.

[0069] In this embodiment, the temperature control device 4 is connected to the heating part 32 of the evaporation container 3, so that the temperature of the heating part 32 is controlled by the temperature control device. Specifically, the temperature control device 4 can control the heating part 32 to heat the crucible 31 to a first preset temperature (for example: 400°C) and continue for a first preset time (for example: 2 hours) so that the mixture powder is fully melted and reacted. In addition, the temperature control device 4 can also control the heating part 32 to heat the crucible 31 to a second preset temperature (for example: 600°C) and continue for a second preset time until the evaporation is completed. It can be understood that the first preset temperature is between the melting point and the boiling point of the mixture powder, and the second preset temperature is greater than the boiling point of the mixture powder.

[0070] In summary, the embodiment of the present invention successfully prepared the Cs5Cu3Cl6I2 thin film through a simplified single-furnace evaporation method, which not only omits the traditional Bridgman single crystal preparation process, but also reduces the process steps and required equipment, reduces energy consumption, and improves the utilization rate of raw materials. In addition, this thin film evaporation method is simple to operate and has a wide range of applicability. It can be used for other materials that can react in a molten or partially solution state, thereby significantly improving production efficiency and the scope of application of materials.

[0071] 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.

[0072] The term "formed" as used in the present invention means that the process can be obtained by one of a variety of processes and is not limited to the processes listed in the embodiments. The order of steps in the present invention can be changed according to actual needs, the order of steps can be changed, and serial processing can also be changed to parallel processing, which is not limited to the order of steps listed in the embodiments.

[0073] It should be noted that the orientation or position relationship indicated by the terms "thickness", "upper" and "lower" are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0074] 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.

[0075] The above is a detailed description of the thin film evaporation method and device for multi-component complex compounds 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 thin film evaporation method for a multi-component complex compound, characterized in that The steps include: Based on the chemical composition of the film to be evaporated, the required compound powder is prepared; Mixing the compound powders according to a preset molar ratio to obtain a mixture powder; Adding the mixed powder into a vapor deposition container and sealing the vapor deposition container; Placing the substrate on a vapor deposition plate; wherein the vapor deposition plate is located directly above the vapor deposition container; The evaporation container is heated to a first preset temperature by a temperature control device and is kept for a first preset time so that the mixture powder can fully melt and react; wherein the first preset temperature is between the melting point and the boiling point of the mixture powder; When the mixed powder is continuously heated at the first preset temperature for the first preset time, the temperature of the evaporation container is raised to a second preset temperature by the temperature control device, and the evaporation container is opened to start evaporation; wherein the second preset temperature is greater than the boiling point of the mixed powder; Continue evaporation until a second preset time or a preset film thickness is reached, and then turn off the temperature control device; The film was cooled to room temperature to obtain a vapor-deposited film.

2. The thin film evaporation method according to claim 1, characterized in that: The thin film to be evaporated corresponds to a plurality of configuration combinations, each of which includes a plurality of compounds, and the molar ratio of each compound in each of which is different.

3. The thin film evaporation method according to claim 2, characterized in that: The film to be evaporated is a Cs5Cu3Cl6I2 film, the plurality of compounds include CsCl, CuCl and CuI, and the molar ratio of CsCl, CuCl and CuI is 5:1:

2.

4. The thin film evaporation method according to claim 2, characterized in that: The film to be evaporated is a Cs5Cu3Cl6I2 film, the multiple compounds include CsI, CsCl and CuCl, and the molar ratio of CsI, CsCl and CuCl is 2:3:

3.

5. The thin film evaporation method according to claim 3 or 4, characterized in that: The first preset temperature is 380-420° C., and the first preset time is not less than 2 hours.

6. The thin film evaporation method according to claim 3 or 4, characterized in that: The second preset temperature is not less than 600° C., and the second preset time is proportional to the mass of the mixture powder.

7. The thin film evaporation method according to claim 1, characterized in that Adding the mixed powder into a vapor deposition container specifically comprises: Under the protection of inert gas, the mixture powder is fully ground using a planetary ball mill to obtain a finely ground mixture powder; The ground mixture powder is weighed to add a preset mass of the mixture powder into the evaporation container.

8. The thin film evaporation method according to claim 2, characterized in that: When the first preset temperature and the second preset temperature are set, the values ​​remain unchanged during the entire evaporation process.

9. A thin film evaporation device for multi-component complex compounds, characterized in that include: A vapor deposition chamber having a closable hollow inner cavity; An evaporation plate is disposed in the hollow inner cavity for placing a substrate; An evaporation container is disposed in the hollow inner cavity and below the evaporation plate to contain the mixture powder; A temperature control device, disposed in the hollow inner cavity and in contact with the evaporation container, for controlling the heating temperature and heating time of the evaporation container according to the chemical composition of the mixed powder; The temperature control device is used to heat the evaporation container to a first preset temperature and keep it for a first preset time so that the mixture powder can fully melt and react; wherein the first preset temperature is between the melting point and boiling point of the mixture powder; The temperature control device is also used to heat the evaporation container to a second preset temperature and continue for a second preset time until the evaporation is completed; wherein the second preset temperature is greater than the boiling point of the mixed powder.

10. The thin film evaporation device according to claim 9, 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.

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