High vacuum coating equipment and coating process

Abstract

The present invention discloses a high vacuum coating equipment and coating process, including the following processing areas: oil spraying area: used for spraying shielding oil; vacuum evaporation area: used for heating the evaporation source to evaporate to the surface of the base film; normal temperature cooling area: used for blowing air on the surface of the base film; instantaneous heating area: used for rapid heating of the base film; low temperature condensation area: used for cooling the base film; high vacuum processing area: negative pressure device is used for extracting vacuum, laser emission device is used for roughening and removing impurities from the coating; transmission device: used for driving the base film to move, and connecting the above-mentioned processing areas in sequence. The present invention sprays shielding oil on the specified position of the base film before evaporation, so that the evaporated metal adheres to the shielding oil. After the evaporation is completed, the base film is instantaneously heated, the shielding oil on the base film is quickly evaporated, and the metal coating also falls off; the laser emission device is used to roughen and remove impurities from the metal coating, enhance the adsorption performance of the metal coating, and ensure that the metal coating is uniform and delicate.

Description

Technical Field

[0001] The present invention relates to the field of vacuum evaporation technology, and in particular to a high vacuum coating device and a coating process. Background Art

[0002] Vacuum evaporation refers to a process in which the coating material is evaporated and gasified by a certain heating evaporation method under vacuum conditions, and the particles evaporate to the surface of the substrate and condense into a film. Evaporation is an earlier and more widely used vapor deposition technology, with the advantages of simple film formation method, high film purity and density, and unique film structure and performance.

[0003] Vacuum evaporation is mostly used for optical materials, electronic components, etc. The common vacuum coating equipment on the market currently performs evaporation in a vacuum environment. After evaporation, the coating material is quickly cooled to quickly condense the deposited metal layer on it, making the metal a solid structure. Finally, air is introduced to end the evaporation process.

[0004] The above-mentioned evaporation process can effectively avoid oxidation reactions and prevent the entry of dust and impurities because it is carried out in a vacuum environment. However, there is still a problem of poor adhesion of the metal coating. On the one hand, this is related to the type of metal of the coating, and on the other hand, it is also affected by the evaporation equipment and process. At the same time, the above-mentioned evaporation process can only be used for evaporation on the entire surface of the coating material. For some evaporation processes with specific requirements, such as thin film capacitors that require a mesh metal coating to be evaporated on the base film, the above-mentioned process is difficult to meet the requirements. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention aims to provide a high vacuum coating device and a coating process to solve the problems of poor adhesion of the metal coating in the evaporation process in the prior art and the inability to select an area for evaporation. The specific technical solution is as follows:

[0006] A high vacuum coating equipment, including the following processing areas:

[0007] Oil spraying area: including an oil spraying device, used for spraying shielding oil at a designated position on the surface of the base film;

[0008] Vacuum evaporation area: including an evaporation device with a metal evaporation source installed inside, used to heat the metal evaporation source inside and evaporate it onto the surface of the base film;

[0009] Normal temperature cooling zone: including a blasting device, used to blast air on the surface of the base film so that the base film forms a relatively stable metal coating;

[0010] Instantaneous heating zone: including instantaneous heating device, used to quickly heat the base film, so that the shielding oil on the base film evaporates quickly and the metal coating outside the shielding oil falls off;

[0011] Low temperature condensation zone: including cooling device, used to cool the base film and gradually condense the metal coating;

[0012] High vacuum treatment area: including a negative pressure device and a laser emitting device, wherein the negative pressure device is used to extract the air in the high vacuum treatment area to form a closed vacuum environment, and the laser emitting device is used to roughen and remove impurities from the coating on the surface of the base film;

[0013] Transmission device: used to drive the base film to move, and sequentially connect the oil injection area, vacuum evaporation area, normal temperature cooling area, instantaneous heating area, low temperature condensation area and high vacuum treatment area.

[0014] As a preferred embodiment, the high vacuum processing area further comprises a scanning device, the scanning device is electrically connected to a control processing unit, and the control processing unit controls the operation of the laser emitting device and the transmission device.

[0015] By setting up scanning equipment, areas that are not processed properly during laser processing can be screened out and scanned again. In some processes, the scanning equipment can be omitted and a second scan can be performed directly. The process flow is simpler, but the processing efficiency is slightly lower and the cost is higher.

[0016] As a preferred embodiment, the blowing device blows air perpendicularly to the surface of the base film.

[0017] The purpose of setting up an air blowing device to blow air vertically on the surface of the base film is to prevent the metal coating from diffusing laterally, so that it can be stably adsorbed on the surface of the base film, and at the same time, the metal is cooled and gradually solidified, thereby improving the stability of the metal coating.

[0018] As a preferred embodiment, the transmission device includes an unwinding roller, a winding roller and a plurality of guide rollers for winding the base film, and a driving motor for driving the winding roller to rotate.

[0019] By setting up unwinding rollers, winding rollers and guide rollers to convey the base film, it is convenient to adjust the process path, realize automatic transportation of the base film, and improve the efficiency of the process flow.

[0020] As a preferred embodiment, the instantaneous heating zone, the low-temperature condensation zone and the high vacuum treatment zone are arranged in sequence from bottom to top.

[0021] By arranging the instantaneous heating zone, the low-temperature condensation zone and the high vacuum processing zone in sequence from bottom to top, on the one hand, each processing area and equipment has a high degree of integration, which is conducive to cost control and improving process efficiency; on the other hand, it is convenient to adjust the direction of the metal coating. For example, during the evaporation process, the metal coating is located below the base film, and during the laser processing process, the metal layer is located above the base film. This can be achieved by simply setting a guide roller to reverse the base film.

[0022] The present invention also provides a coating process, using the above-mentioned high vacuum coating equipment, comprising the following steps:

[0023] S1: Cleaning and pretreatment: Clean, dry and preheat the basement membrane to improve the surface activity of the basement membrane;

[0024] S2: Spraying shielding oil: Determine the area on the base film where the shielding oil needs to be sprayed, and prepare an oil spray plate with spraying ports. The oil spray device sprays the shielding oil onto the surface of the base film through the openings on the oil spray plate.

[0025] S3: Evaporation of metal layer: heating the evaporation container to evaporate or sublimate the metal in the evaporation container, gradually filling the entire evaporation area, making the evaporation area gradually tend to be vacuum, and the metal evaporates or sublimates to the surface of the base film or the outside of the shielding oil sprayed on the surface of the base film;

[0026] S4: Cooling at room temperature: Cooling the evaporated base film at room temperature, and blowing air toward the surface of the base film to form a relatively stable metal coating on the surface of the base film;

[0027] S5: Instantaneous heating: Instantaneously heat the base film to make the shielding oil on the surface of the base film evaporate quickly, and at the same time, the metal coating outside the shielding oil falls off along with the shielding oil;

[0028] S6: Low temperature condensation: cool the base film so that the metal coating on the surface of the base film gradually condenses to form a uniform and stable coating;

[0029] S7: High vacuum laser processing: Place the base film in a high vacuum chamber, and use a laser transmitter to emit laser to the metal coating on the surface of the base film to roughen and remove impurities from the metal coating;

[0030] S8: Quality inspection and winding: Measure the thickness of the metal coating on the base film, observe the density of the metal coating, and wind and store those that meet the standards.

[0031] As a preferred embodiment, the base film is cleaned by organic solvent cleaning and / or ultrasonic cleaning in step S1.

[0032] By cleaning with organic solvents and / or ultrasonic waves to remove impurities and dirt on the surface of the base film, the metal will be of higher purity during vapor deposition and will be less susceptible to impurities, thus improving the adhesion of the metal.

[0033] As a preferred embodiment, in step S7, after emitting laser to the metal coating on the surface of the base film, the metal coating is scanned by a scanning device, the scanned image is analyzed and compared with the set standard, and secondary laser processing is performed on the areas that do not meet the standard.

[0034] By setting up a scanning device to scan the metal coating on the surface of the base film, the area that was not processed in the first laser processing is obtained, and then a second scan is performed, the uniformity and density of the metal coating are improved, and there is no need to scan the entire area twice, thereby optimizing costs.

[0035] As a preferred implementation, the method of analyzing the scanned image and comparing it with the set standard includes:

[0036] The scanned image is divided into rectangular areas of several unit areas, the average gray value of the pixels in each rectangular area is analyzed, and compared with the set standard gray value, and the candidate areas whose average gray value does not meet the set gray value are screened out;

[0037] The metal bumps in the screened candidate areas are judged and compared with the metal bumps in the database. A comparative analysis is performed from three dimensions: shape, area, and pixel value. The number of metal bumps in the screened candidate areas is calculated, and the candidate areas that do not meet the quantity standard are subjected to secondary laser processing as a whole.

[0038] First, the image is divided into several rectangular areas of unit area, and the average grayscale value of the pixels in the rectangular area is calculated to preliminarily screen out the candidate areas where the metal coating density does not meet the standard. Then, the number of metal coating points in the candidate areas is determined, and the areas with density that do not meet the standard are screened out more accurately within this smaller range per unit area, and then further roughening and impurity removal are performed by laser.

[0039] As a preferred embodiment, the step of scanning the metal coating also includes: using a high-frequency measuring probe to measure the average resistance value of the metal coating in a unit area, and calculating the average thickness of the metal coating based on the average resistance value and the unit area, comparing it with the standard thickness range, and screening out areas that do not meet the standard thickness range.

[0040] The scanning device and the high-frequency measuring probe can be set on the same component, saving space and equipment costs. At the same time, the average resistance of the metal coating can be measured after laser processing, and then the average thickness of the metal coating can be calculated, which is convenient for subsequent quality inspection and reprocessing of the processed film.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] The present invention sprays shielding oil on a designated position of the base film before evaporation, so that the evaporated metal adheres to the shielding oil. After the evaporation is completed, the base film is instantaneously heated, the shielding oil on the base film is quickly evaporated, and the metal coating outside the shielding oil also falls off, so that the area of ​​the metal coating can be selected;

[0043] At the same time, the process of instantaneously heating the base film can enhance the surface activity of the base film, so that the metal coating can be stably adsorbed on the surface of the base film;

[0044] In addition, after the evaporation is completed, the metal coating is roughened and decontaminated by a laser emitting device to enhance the adsorption performance of the metal coating, ensure that the metal coating is uniform and delicate, and its conductive performance is also better. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 A distribution diagram of processing areas of the high vacuum coating equipment disclosed in the present invention;

[0046] Figure 2 It is a process flow chart of the coating process disclosed in the present invention. DETAILED DESCRIPTION

[0047] The embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0048] The following describes the embodiments of the present disclosure through specific examples, and those skilled in the art can easily understand other advantages and effects of the present disclosure from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all of the embodiments. The present disclosure can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present disclosure. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present disclosure.

[0049] like Figure 1 As shown, a high vacuum coating equipment is mainly used for evaporating a metal coating on a base film, which mainly includes an oil spraying area, a vacuum evaporation area, a normal temperature cooling area, an instantaneous heating area, a low temperature condensation area and a high vacuum processing area, and each of the above processing areas is connected in sequence by a transmission device. The transmission device is mainly composed of a winding roller, a tensioning device, a drive motor unwinding roller and a plurality of guide rollers, which are used to tension the base film and drive the base film to drive, and the drive motor is controlled by a controller to start and stop and the speed.

[0050] This embodiment takes the evaporation of aluminum zinc as an example:

[0051] The oil spraying area includes a spraying device and a baffle, and a plurality of openings are provided on the baffle for spraying the shielding oil on a designated area on the surface of the base film;

[0052] The vacuum evaporation area includes an evaporation device, which includes containers such as a crucible and an evaporation boat, a heating device, and a spray plate. In this embodiment, aluminum is placed in the crucible, and zinc is placed in the evaporation boat. The aluminum is heated first, and then the zinc is heated, so that the vacuum evaporation area is filled with metal vapor, almost forming a vacuum, with white aluminum on both sides of the base film and black zinc in the middle. The metal evaporates or sublimates to the bottom of the base film to form a metal coating, which is located outside the base film and the shielding oil.

[0053] Among them, the normal temperature cooling zone includes an air blowing device, which blows air vertically toward the surface of the base film to cool and solidify the metal coating, forming a relatively stable coating. At the same time, it avoids lateral diffusion of the metal and increases the adsorption force of the metal coating on the base film.

[0054] Among them, the instantaneous heating zone includes a high-temperature hot air gun, which is used to spray high-temperature hot air to the side of the base film surface where the metal coating is located. The shielding oil on the base film evaporates rapidly, and the metal coating outside the shielding oil falls off along with the shielding oil. The metal coating that has been evaporated on the surface of the base film has been cooled in the normal temperature cooling zone, and its heating rate is slower than that of the shielding oil. It can still maintain a relatively stable state and is not easy to evaporate again.

[0055] Among them, the low-temperature condensation zone includes a cooling device, specifically including thermal insulation parts, air cooling and other equipment, which are used to gradually reduce the temperature of the surface of the base film, gradually condense the metal coating, and form a stable and uniform coating layer.

[0056] Among them, the high vacuum processing area includes a laser emitting device, a negative pressure device, a scanning device and a high-frequency detection probe. Negative pressure devices such as common vacuum generators are used to draw the high vacuum processing area into a closed vacuum space, so that the laser emitting device can effectively remove impurities when emitting lasers to the metal coating, and roughen the metal coating to make it more uniform and dense. The scanning device is used to scan the metal coating and send it back to the controller. The controller determines the uniformity and density of the metal coating and determines whether it needs to be re-scanned. The high-frequency detection probe is used to detect the average resistance value of the metal coating, and calculate its average thickness based on the detection area of ​​the metal coating for quality inspection.

[0057] Among them, the instantaneous heating zone, low-temperature condensation zone and high vacuum treatment zone are arranged from bottom to top in sequence. On the one hand, the integration is high, which optimizes the cost and process efficiency. On the other hand, the metal coating on the base film is adjusted to face upward or downward through the setting of the guide roller, which facilitates the processing of the base film surface in each processing area.

[0058] like Figure 2 As shown, a coating process comprises at least the following steps:

[0059] S1: Cleaning and pretreatment: Clean, dry and preheat the basement membrane to improve the surface activity of the basement membrane;

[0060] The cleaning method may be organic solvent cleaning or ultrasonic cleaning to enhance the oxidation activity of the surface of the base film and improve its adhesion;

[0061] S2: Spraying shielding oil: Determine the area on the base film where the shielding oil needs to be sprayed, and prepare an oil spray plate with spraying ports. The oil spray device sprays the shielding oil onto the surface of the base film through the openings on the oil spray plate.

[0062] Wherein, the oil spraying device is located below the roll to spray the base film on the roll;

[0063] S3: Evaporation of metal layer: heating the evaporation container to evaporate or sublimate the metal in the evaporation container, gradually filling the entire evaporation area, making the evaporation area gradually tend to be vacuum, and the metal evaporates or sublimates to the surface of the base film or the outside of the shielding oil sprayed on the surface of the base film;

[0064] Among them, the electrical properties of the evaporated metal can be adjusted by changing the expansion coefficient of the nozzle opening on the nozzle plate;

[0065] S4: Cooling at room temperature: Cooling the evaporated base film at room temperature, and blowing air toward the surface of the base film to form a relatively stable metal coating on the surface of the base film;

[0066] Wherein, the blower blows air vertically toward the surface of the base film;

[0067] S5: Instantaneous heating: Instantaneously heat the base film to make the shielding oil on the surface of the base film evaporate quickly, and at the same time, the metal coating outside the shielding oil falls off along with the shielding oil;

[0068] In particular, since the metal coating has been cooled in step S4, it is not easily affected by instantaneous heating and will not easily evaporate again;

[0069] S6: Low temperature condensation: cool the base film so that the metal coating on the surface of the base film gradually condenses to form a uniform and stable coating;

[0070] The cooling process of the base film needs to be carried out gradually, and try to avoid damage to the metal coating caused by cooling too quickly in a short period of time;

[0071] S7: High vacuum laser processing: Place the base film in a high vacuum chamber, and use a laser transmitter to emit laser to the metal coating on the surface of the base film to roughen and remove impurities from the metal coating;

[0072] Among them, a scanning device is also set in the high vacuum chamber to scan the metal coating, divide the scanned image into several rectangular areas of unit area, analyze the average gray value of the pixels in each rectangular area, compare it with the set standard gray value, and screen out the candidate areas whose average gray value does not meet the set gray value. The candidate areas have gray values ​​of pixels on the surface that do not meet the standard due to inadequate laser processing;

[0073] The metal bumps in the screened candidate areas are judged and compared with the metal bumps in the database. A comparative analysis is performed from three dimensions: shape, area, and pixel value. The number of metal bumps in the screened candidate areas is calculated, and the candidate areas that do not meet the quantity standard are subjected to secondary laser processing as a whole.

[0074] The number of metal bumps in the candidate area is directly related to the density of the metal coating. The higher the density, the denser the metal bumps. Therefore, the candidate areas that do not meet the standards require secondary laser processing and roughening.

[0075] S8: Quality inspection and winding: Measure the thickness of the metal coating on the base film, observe the density of the metal coating, and wind and store those that meet the standards.

[0076] The processed metal film is rolled up on the roller, and when it is needed, it can be unrolled and cut directly using the unwinding device, which is very convenient.

[0077] In the description of the present invention, it is necessary to understand that the terms "middle", "length", "up", "down", "front", "back", "vertical", "horizontal", "inside", "outside", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply 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.

[0078] In the present invention, unless otherwise clearly specified and limited, the first feature "on" the second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. "Multiple" means at least two, such as two, three, etc., unless otherwise clearly and specifically limited.

[0079] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0080] The above is only for explaining the implementation mode of the present invention and is not intended to limit the present invention. For those skilled in the art, any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention without creative work should be included in the protection scope of the present invention.

Claims

1. A high vacuum coating equipment, It is characterized in that The following processing areas are included: Oil spraying area: including an oil spraying device, used for spraying shielding oil at a designated position on the surface of the base film; Vacuum evaporation area: including an evaporation device with a metal evaporation source installed inside, used to heat the metal evaporation source inside and evaporate it onto the surface of the base film; Normal temperature cooling zone: including a blasting device, used to blast air on the surface of the base film so that the base film forms a relatively stable metal coating; Instantaneous heating zone: including instantaneous heating device, used to quickly heat the base film, so that the shielding oil on the base film evaporates quickly and the metal coating outside the shielding oil falls off; Low temperature condensation zone: including cooling device, used to cool the base film and gradually condense the metal coating; High vacuum treatment area: including a negative pressure device and a laser emitting device, wherein the negative pressure device is used to extract the air in the high vacuum treatment area to form a closed vacuum environment, and the laser emitting device is used to roughen and remove impurities from the coating on the surface of the base film; Transmission device: used to drive the base film to move, and sequentially connect the oil injection area, vacuum evaporation area, normal temperature cooling area, instantaneous heating area, low temperature condensation area and high vacuum treatment area.

2. The high vacuum coating equipment according to claim 1, It is characterized in that The high vacuum processing area also includes a scanning device, which is electrically connected to a control processing unit, and the control processing unit controls the operation of the laser emitting device and the transmission device.

3. The high vacuum coating equipment according to claim 1, It is characterized in that The air blowing device blows air perpendicularly to the surface of the base film.

4. The high vacuum coating equipment according to claim 1, It is characterized in that The transmission device comprises an unwinding roller, a winding roller and a plurality of guide rollers for winding the base film, and a driving motor for driving the winding roller to rotate.

5. The high vacuum coating device according to any one of claims 1 to 4, It is characterized in that The instantaneous heating zone, the low-temperature condensation zone and the high-vacuum processing zone are arranged in sequence from bottom to top.

6. A coating process, It is characterized in that Using the high vacuum coating equipment according to any one of claims 1 to 5, The following steps are involved: S1: Cleaning and pretreatment: Clean, dry and preheat the basement membrane to improve the surface activity of the basement membrane; S2: Spraying shielding oil: Determine the area on the base film where the shielding oil needs to be sprayed, and prepare an oil spray plate with spraying ports. The oil spray device sprays the shielding oil onto the surface of the base film through the openings on the oil spray plate. S3: Evaporation of metal layer: heating the evaporation container to evaporate or sublimate the metal in the evaporation container, gradually filling the entire evaporation area, making the evaporation area gradually tend to be vacuum, and the metal evaporates or sublimates to the surface of the base film or the outside of the shielding oil sprayed on the surface of the base film; S4: Cooling at room temperature: Cooling the evaporated base film at room temperature, and blowing air toward the surface of the base film to form a relatively stable metal coating on the surface of the base film; S5: Instantaneous heating: Instantaneously heat the base film to make the shielding oil on the surface of the base film evaporate quickly, and at the same time, the metal coating outside the shielding oil falls off along with the shielding oil; S6: Low temperature condensation: cool the base film so that the metal coating on the surface of the base film gradually condenses to form a uniform and stable coating; S7: High vacuum laser processing: Place the base film in a high vacuum chamber, and use a laser transmitter to emit laser to the metal coating on the surface of the base film to roughen and remove impurities from the metal coating; S8: Quality inspection and winding: Measure the thickness of the metal coating on the base film, observe the density of the metal coating, and wind and store those that meet the standards.

7. The coating process according to claim 6, It is characterized in that In step S1, the base film is cleaned by organic solvent cleaning and / or ultrasonic cleaning.

8. The coating process according to claim 6, It is characterized in that In step S7, after emitting laser light to the metal coating on the surface of the base film, the metal coating is scanned by a scanning device, and the scanned image is analyzed and compared with the set standard, and secondary laser processing is performed on the area that does not meet the standard.

9. The coating process according to claim 8, It is characterized in that Methods for analyzing scanned images and comparing them with set standards include: The scanned image is divided into rectangular areas of several unit areas, the average gray value of the pixels in each rectangular area is analyzed, and compared with the set standard gray value, and the candidate areas whose average gray value does not meet the set gray value are screened out; The metal bumps in the screened candidate areas are judged and compared with the metal bumps in the database. A comparative analysis is performed from three dimensions: shape, area, and pixel value. The number of metal bumps in the screened candidate areas is calculated, and the candidate areas that do not meet the quantity standard are subjected to secondary laser processing as a whole.

10. The coating process according to claim 8, It is characterized in that The step of scanning the metal coating also includes: using a high-frequency measuring probe to measure the average resistance value of the metal coating in a unit area, and calculating the average thickness of the metal coating based on the average resistance value and the unit area, comparing it with the standard thickness range, and screening out areas that do not meet the standard thickness range.

Images