Method for growing high-flux thin film material by using rotary mask

Abstract

The invention belongs to the technical field of material preparation, and particularly relates to a method for growing a high-flux thin film material by using a rotating mask. The method comprises the following steps that under the ultrahigh vacuum condition, a substrate is placed in a mask structure, the mask structure is provided with an opening, and the substrate is located under the opening; the mask structure is placed in ultrahigh vacuum evaporation equipment, a vacuum evaporation method is adopted, according to the components of the thin film material, the corresponding components are subjected to evaporation deposition on the substrate in the mask structure through the opening in sequence, the mask structure is rotated after evaporation deposition, and next evaporation deposition is carried out; wherein the components of the next evaporation deposition and all the components of the previous evaporation deposition are partially overlapped until all the components are evaporated and deposited, and the thin film material is obtained. The rotary mask method is simple to operate, and repeated manual operation is reduced and the experiment success rate is improved by depositing a thin film material formed by combining multiple components on one substrate.

Description

Technical Field

[0001] The invention belongs to the technical field of material preparation, and in particular relates to a method for growing high-throughput thin film materials using a rotating mask. Background Art

[0002] Surface science research is usually carried out in an ultra-high vacuum environment, mainly because the ultra-high vacuum environment can accurately control surface chemistry experiments.

[0003] Low-dimensional nanostructures refer to materials with at least one dimension in the nanoscale range. Due to size and quantum effects, they exhibit significantly different properties from macroscopic materials in terms of acoustics, optics, electricity, and magnetism. With the support of surface science methods, such materials are precisely synthesized in an ultra-high vacuum environment through a "bottom-up" approach, and are precisely designed and controlled at the molecular or atomic level, giving them unique performance advantages.

[0004] However, due to the complexity of the molecular structure itself, its design often requires a series of repeated experiments, and growing thin film materials under ultra-high vacuum often requires experimenters to spend a lot of time and energy to prepare samples and characterize them. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a method for growing high-throughput thin film materials using a rotating mask.

[0006] The present invention designs a mask rotation mask method and a mask structure, and places the mask structure equipped with a substrate in an ultra-high vacuum evaporation device; the vacuum evaporation method is used to sequentially evaporate and deposit the corresponding components on the substrate in the mask structure according to the components of the thin film material, and the mask structure is rotated after each evaporation and deposition, so that the components evaporated and deposited next time partially overlap with all the components evaporated and deposited last time; a new material with a combination of multiple components is prepared by cross-mixing multiple components on the substrate. The present invention can quickly synthesize and test materials with a combination of multiple components through high-throughput experiments and characterizations, and accelerate the discovery process of new materials; and can greatly reduce the number and time of trial and error experiments in traditional material research methods, and improve the accuracy and efficiency of material design. At the same time, the present invention can accelerate the number of experiments required for the growth of thin film materials in an ultra-high vacuum environment, reduce manpower requirements and improve efficiency, and improve the repeatability and reliability of experiments.

[0007] The object of the present invention is to provide a method for growing a high-throughput thin film material using a rotating mask, comprising the following steps: Step 1: Under ultra-high vacuum conditions, place a substrate in a mask structure, wherein the mask structure is provided with an opening and the substrate is located directly below the opening.

[0008] It should be noted that the ultra-high vacuum condition in the present invention needs to be obtained through extraction by a pump group including a mechanical pump, a vacuum pump, a titanium pump and an ion pump, and is obtained by baking and degassing the components in the vacuum chamber. The present invention should perform a leak test on the equipment before obtaining an ultra-high vacuum. The specific operation is as follows: turn on the mechanical pump, turn on the vacuum pump after the mechanical pump is stable, wait for a period of time after the vacuum pump current is stable, and when the equipment pressure is 1E -6 mbar, the equipment is sealed intact. The specific operation of the present invention to obtain ultra-high vacuum is as follows: confirm that the equipment is sealed intact, start baking and turn on the ion pump; when the equipment pressure reaches 3E -7 mbar, stop baking; then use the ion pump and titanium pump to degas the equipment in sequence until the pressure is lower than 1E - 9 mbar.

[0009] Preferably, the baking temperature is 110°C to 120°C.

[0010] It should also be noted that under ultra-high vacuum conditions, each operation needs to be manipulated by a built-in manipulator; before the present invention places the substrate in the mask structure for molecular evaporation deposition, the substrate needs to be pre-treated, and the substrate is ion sputtered using an ion gun and then annealed to obtain a clean and flat substrate surface. Preferably, the substrate is a metal single crystal. The present invention then places the pre-treated substrate in the mask structure by manipulating the built-in manipulator; wherein the mask structure is provided with an opening, and the substrate is located directly below the opening, thereby ensuring that the vacuum evaporated molecules can be deposited on the substrate through the opening of the mask structure.

[0011] Step 2: placing the mask structure in an ultra-high vacuum evaporation device, and using a vacuum evaporation method, according to the components of the thin film material, sequentially evaporating and depositing the corresponding components through the openings on the substrate in the mask structure, rotating the mask structure after evaporation and deposition, and then performing the next evaporation and deposition; wherein the components of the next evaporation and deposition partially overlap with all the components of the previous evaporation and deposition, until the evaporation and deposition of all components are completed, thereby obtaining a thin film material.

[0012] It should be noted that the component evaporation source in the ultra-high vacuum evaporation equipment includes three or more component evaporation ports, which can be loaded with three or more components at one time. Each evaporation port is controlled by a separate DC power supply to evaporate the component. The evaporation temperature of different components is different, and the required current size is also different. When multiple components are evaporated and deposited, multiple component evaporation sources are loaded in the component evaporation port, and the evaporation of each component in the component evaporation port is controlled in turn. In addition, a quartz crystal microbalance is required to detect whether the component is evaporated and calculate the evaporation rate. Preferably, an organic component evaporation source is used for component evaporation.

[0013] When the component is stably evaporated, align the substrate in the mask structure with the evaporation port of the component being evaporated in the organic component evaporation source; start timing after alignment, turn off the component evaporation source when the evaporation time is reached, and move the deposited mask structure to one side to complete a component deposition. When the evaporation time is reached, the evaporation deposition is completed, and the DC power supply needs to be turned off immediately, and the manipulator needs to be manipulated to move the mask structure to one side. In addition, the evaporation time needs to be controlled to ensure that the coverage of each component is required for the experiment.

[0014] It should also be noted that after each evaporation deposition, the DC power supply needs to be turned off immediately and the mask structure needs to be moved to one side; then the mask structure is rotated, and the angle of each rotation is determined according to the type of thin film material component. Preferably, the angle of each rotation is 360° / component type. After the mask structure is rotated, the mask structure is aligned with the evaporation port of the component being evaporated in the organic component evaporation source, and the next evaporation is performed. The components of the next evaporation deposition partially overlap with all the components of the previous evaporation deposition; until all the multiple component evaporation sources of the component evaporation port are evaporated, a thin film material with a combination of multiple components is obtained.

[0015] Preferably, the rotating mask structure comprises: a rotatable mask cover and a sample holder.

[0016] A through hole is provided at the upper end of the sample rack, and a plurality of annular plates are arranged along the circumference of the through hole for mounting the mask cover on the sample rack through an annular guide rail; a cavity is arranged inside the sample rack for placing a substrate.

[0017] The bottom of the mask cover is provided with an annular groove, the structure of which matches the structure of the plurality of annular plates; the center of the bottom of the mask cover is provided with a small hole for depositing molecules in the evaporation process onto the substrate of the sample holder through the small hole.

[0018] Preferably, a plurality of paddles are circumferentially distributed on the outer side of the mask cover to facilitate the robot arm to clamp and rotate the mask cover.

[0019] Preferably, a mark is provided above one of the paddles of the mask cover for observing the rotation of the mask cover.

[0020] Compared with the prior art, the present invention has the following beneficial effects: The present invention places a mask structure equipped with a substrate in an ultra-high vacuum evaporation device, wherein the mask structure is provided with an opening, and the substrate is located directly below the opening; the present invention sequentially evaporates and deposits the corresponding components through the opening on the substrate in the mask structure according to the components of the thin film material, and rotates the mask structure after evaporation and deposition, and then performs the next evaporation and deposition, so that the components of the next evaporation and deposition partially overlap with all the components of the previous evaporation and deposition; a thin film material with a combination of multiple components is prepared by cross-mixing multiple components on the substrate. The present invention realizes the deposition of multiple components on the surface of a single substrate in an ultra-high vacuum environment through a rotating mask method, and can quickly prepare high-quality thin film materials with a combination of multiple components, accelerate the discovery process of new materials, and effectively improve the experimental efficiency of surface thin film material growth. The present invention can greatly reduce the number and time of trial and error experiments in traditional material research methods, and improve the accuracy and efficiency of material design.

[0021] The rotary mask method provided by the present invention is simple to operate. By depositing multiple components on one substrate, it can accelerate the number of experiments required for the growth of thin film materials in an ultra-high vacuum environment, reduce manpower requirements, improve efficiency, and enhance the repeatability and reliability of the experiment.

[0022] The mask device provided by the present invention is simple in design and easy to use, and can be widely used in the growth of thin film materials in various situations. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the structure of the mask structure of the present invention.

[0024] Figure 2 Schematic diagram of the structure of the sample holder of the present invention.

[0025] Figure 3 It is a schematic structural diagram of the mask cover of the present invention.

[0026] Figure 4 It is a schematic structural diagram of the bottom of the mask cover of the present invention.

[0027] Figure 5 This is a scanning probe microscopic image of the thin film material prepared in Example 1 of the present invention.

[0028] Figure 6 This is a scanning probe microscopic image of the thin film material prepared in Example 2 of the present invention.

[0029] Figure numerals: 1 - mask cover; 2 - sample holder; 3 - through hole; 4 - annular plate; 5 - cavity; 6 - annular groove; 7 - small hole; 8 - pick; 9 - mark. DETAILED DESCRIPTION

[0030] In order to enable those skilled in the art to better understand that the technical solution of the present invention can be implemented, the present invention is further described below in conjunction with specific embodiments and drawings. It is obvious that 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.

[0031] The following will be combined Figure 1~Figure 4 , further illustrating a specific implementation of the mask structure of the present invention.

[0032] The mask structure provided in this embodiment is as follows Figure 1 As shown, the mask structure includes: a rotatable mask cover 1 and a sample holder 2.

[0033] like Figure 1 and Figure 2 As shown, a through hole 3 is opened at the upper end of the sample holder 2, and a plurality of annular plates 4 are arranged along the circumference of the through hole 3; a cavity 5 is arranged inside the sample holder 2 for placing a substrate.

[0034] like Figure 4 As shown, the mask cover 1 is provided with an annular groove 6 at the bottom, and the structure of the annular groove 6 matches the structure of the multiple annular plates 4, so as to insert the multiple annular plates 4 into the annular groove 6; a small hole 7 is provided at the center of the bottom of the mask cover 1, so as to deposit the molecules in the evaporation process onto the substrate of the sample holder 2 through the small hole 7.

[0035] like Figure 3 As shown, the outer side of the mask cover 1 is provided with a plurality of paddles distributed along the circumferential direction, so as to facilitate the robot to clamp and rotate the mask cover 1. A mark 9 is provided above one of the paddles 8 of the mask cover 1, for observing the rotation of the mask cover 1.

[0036] Two embodiments of growing high-throughput thin film materials using a rotating mask through a mask structure are provided below.

[0037] It should be noted that the following components are required for the preparation of thin film materials: 4,4'-(2',4',5',6'-tetrayl(4-(pyridin-4-yl)phenyl)-[1,1':3',1''-terphenyl]-4,4''-diyl)bipyridine, denoted as component A; 1,3,5-tris[4-(pyridin-4-yl)phenyl]benzene, denoted as component B; 2,4,6-tris(pyridin-4-yl)-1,3,5-triazine, denoted as component C; 4,4'-di(pyridin-4-yl)-1,1'-biphenyl, denoted as component D; 3,3',5,5'-tetra(pyridin-4-yl)-1,1'-biphenyl, denoted as component E; 4,4'-(1,3-benzenedimethyl)bipyridine, denoted as component F.

[0038] Example 1 This embodiment provides a method for growing high-throughput thin film materials using a rotating mask.

[0039] In this embodiment, component A, component B and component C are selected as components for preparing the film material.

[0040] Step 1: Prepare the mask-substrate: (1.1) Seal the equipment and turn on the vacuum pump to start leak detection; after confirming that the equipment is sealed, bake it and turn on the ion pump; when the equipment pressure reaches 3E -7 mbar when the baking is stopped.

[0041] (1.2) Use the ion pump and titanium pump to degas the equipment in sequence until the pressure is lower than 1E -9 mbar, to obtain an ultra-high vacuum environment.

[0042] (1.3) Select Cu(111) single crystal as the substrate, use an ion gun to perform argon ion sputtering on Cu(111), and then anneal Cu(111) to obtain a pretreated Cu(111) substrate. The parameters for argon ion sputtering are as follows: preset low energy mode; ion acceleration voltage is 1500V, ion gun emission current is 10mA, working time is 10min, and argon concentration in the chamber is 1E -5 mbar. The annealing parameters were set as follows: current 3.8 A, voltage 8.0 V, and annealing time 10 min.

[0043] (1.4) Operate the built-in manipulator to install the mask cover 1 on the sample holder 2 to obtain a mask-sample holder.

[0044] (1.5) The pretreated Cu(111) substrate is placed in the cavity 5 of the mask-sample holder to obtain a mask-Cu(111) substrate.

[0045] S2. Vacuum evaporation deposition: (2.1) Connect the DC power supply to evaporate the components and detect the evaporation rate of each component using a quartz crystal microbalance.

[0046] (2.2) Set the evaporation parameters of component A as follows: current 1.901 A, voltage 3.38 V, component evaporation rate 2.5 A / min.

[0047] (2.3) After component A is stably evaporated, align the small hole 7 in the mask-Cu(111) substrate with the evaporation port of the organic component evaporation source containing component A. Start timing after alignment, and turn off the component evaporation source after the evaporation time is reached. Move the mask-Cu(111) substrate to one side, and the evaporation time is 4 s. The evaporation of component A is completed, i.e., the first deposition is completed, and the first component mask-substrate is obtained, which is recorded as the first assembly.

[0048] (2.4) The mask cover 1 is rotated 120° using the built-in robot.

[0049] (2.5) Set the evaporation parameters of component B as follows: current 1.369 A, voltage 2.51 V, component evaporation rate 2.3 A / min.

[0050] (2.6) After component B is stably evaporated, align the small hole 7 in the first assembly with the evaporation port of the organic component evaporation source containing component B; start timing after alignment, close the component evaporation source after the evaporation time is reached, and move the first assembly to one side. The evaporation time is 10.5 s, and the evaporation of component B is completed, that is, the second deposition is completed. The components deposited for the second time partially overlap with the components deposited for the first time, and a second component mask-substrate composed of three combinations of component A, component B, and cross components of component A and component B is obtained, which is recorded as the second assembly.

[0051] (2.7) The mask cover 1 is further rotated 120° by the built-in robot.

[0052] (2.8) The evaporation parameters of component C are set as follows: current is 1.349 A, voltage is 2.48 V, and component evaporation rate is 2 A / min.

[0053] (2.9) After component C is stably evaporated, align the small hole 7 in the second assembly with the evaporation port of the organic component evaporation source containing component C; start timing after alignment, and close the component evaporation source after the evaporation time is reached; and move the second assembly to one side for 2 seconds to complete the evaporation of component C, i.e., the third deposition is completed. The components deposited for the third time partially overlap with the components deposited for the first time and the components deposited for the second time, so that four combinations of component C, a cross component of component A and component C, a cross component of component B and component C, and a cross component of component A, component B and component C are obtained to obtain a third component mask-substrate, recorded as the third assembly.

[0054] (2.10) After all components are evaporated, the prepared Cu(111) single crystal substrate is taken out from the third assembly by a built-in robot to obtain a thin film material having seven combinations of three components.

[0055] Example 2 This embodiment provides a method for growing high-throughput thin film materials using a rotating mask.

[0056] In this embodiment, component A, component B, component C, component D, component E and component F are selected as components for preparing the film material.

[0057] The difference between this embodiment and embodiment 1 is that this embodiment adds component D, component E and component F on the basis of embodiment 1. And the evaporation parameters of component D, component E and component F are as follows: Component D: current is 1.507A, voltage is 2.23V, component evaporation rate is 2.5A / min, and evaporation time is 2s; component E: current is 1.271A, voltage is 1.89V, component evaporation rate is 2A / min, and evaporation time is 2s; component F: current is 0.847A, voltage is 1.28V, component evaporation rate is 1A / min, and evaporation time is 2s; a thin film material with six components and sixty-three combinations was obtained.

[0058] The thin film materials prepared in Example 1 and Example 2 were subjected to temperature annealing for the thin film materials that were determined to meet the requirements of subsequent experiments. The samples were subjected to temperature annealing by a DC power supply, and the real-time annealing temperature was detected by an infrared thermometer for easy control. The current was 1.7A, the voltage was 2.7V, the annealing temperature was 150°C, and the annealing time was 5min, to obtain the annealed thin film material.

[0059] Experimental test: 1. The thin film materials prepared in Example 1 and Example 2 were characterized by scanning probe microscopy. The coverage of each component on the Cu (111) single crystal substrate was scanned by the probe, wherein the scanning parameters were set as follows: I t is 100 pA, V b is -1.50 V, and the result is Figure 5 shown.

[0060] Figure 5 Scanning probe microscope images of thin film materials with seven combinations of three components prepared in Example 1. Figure 5 The disordered network formed by the coordination of components A, B, and C is shown, and possible combinations of components at different substrate positions are demonstrated. In addition, the single component networks of the three components are all coordinated to copper atoms.

[0061] Figure 6 Scanning probe microscope images of thin film materials with six components and sixty-three combinations prepared in Example 2. Figure 6 The overall structure of the six-component network is shown and appears to be an amorphous phase, where the various components are uniformly distributed and randomly coordinated at random angles.

[0062] It should be noted that the component connection relationships not specifically mentioned in the present invention are assumed to adopt the existing technology. Since they do not involve the invention point and are widely used in the existing technology, the structural connection relationships are not described in detail.

[0063] It should be noted that when the present invention involves a numerical range, it should be understood that the two endpoints of each numerical range and any value between the two endpoints can be selected. Since the steps and methods used are the same as those in the embodiments, in order to avoid redundancy, the present invention describes a preferred embodiment. Although the preferred embodiments of the present invention have been described, once those skilled in the art know the basic creative concept, they can make other changes and modifications to these embodiments, and these changes and modifications all fall within the scope of the present invention.

[0064] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. If these modifications and variations of the present invention fall within the scope of the equivalent technology of the present invention, the present invention is also intended to include these modifications and variations.

Claims

1. A method for growing high-throughput thin film materials using a rotating mask, characterized in that: The following steps are involved: Under ultra-high vacuum conditions, placing a substrate in a mask structure, wherein the mask structure is provided with an opening, and the substrate is located directly below the opening; The mask structure is placed in an ultra-high vacuum evaporation device, and a vacuum evaporation method is used. According to the components of the thin film material, the corresponding components are sequentially evaporated and deposited through the openings on the substrate in the mask structure. After evaporation and deposition, the mask structure is rotated and the next evaporation and deposition is performed; wherein the components of the next evaporation and deposition partially overlap with all the components of the previous evaporation and deposition until the evaporation and deposition of all components are completed to obtain a thin film material.

2. The method for growing high-throughput thin film materials using a rotating mask according to claim 1, characterized in that: The angle of each rotation is determined by the composition of the film material.

3. The method for growing high-throughput thin film materials using a rotating mask according to claim 2, characterized in that: The rotation angle is 360° / component type each time.

4. The method for growing high-throughput thin film materials using a rotating mask according to claim 1, characterized in that: The mask structure comprises: a rotatable mask cover (1) and a sample holder (2); A through hole (3) is provided at the upper end of the sample holder (2), a plurality of annular plates (4) are arranged along the circumference of the through hole (3), and a cavity (5) is provided inside the sample holder (2) for placing a substrate; The bottom of the mask cover is provided with an annular groove (6), the structure of the annular groove (6) matches the structure of the plurality of annular plates (4), and is used for inserting the plurality of annular plates (4) into the annular groove (6); the center of the bottom of the mask cover (1) is provided with a small hole (7), which is used for depositing molecules in the evaporation process onto the substrate of the sample holder (2) through the small hole.

5. The method for growing high-throughput thin film materials using a rotating mask according to claim 4, characterized in that: The outer side of the mask cover (1) is provided with a plurality of paddles (8) distributed in the circumferential direction, so as to facilitate a robot to clamp and rotate the mask cover (1).

6. The method for growing high-throughput thin film materials using a rotating mask according to claim 4, characterized in that: The small hole (7) is a gourd-shaped hole.

7. The method for growing high-throughput thin film materials using a rotating mask according to claim 1, characterized in that: The substrate needs to be pre-treated before being placed on the mask structure. The pre-treatment process is: ion sputtering and annealing the substrate to obtain a clean and smooth substrate surface.

8. The method for growing high-throughput thin film materials using a rotating mask according to claim 1, characterized in that: The substrate is a metal single crystal substrate.

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