Pulsed laser deposition coating apparatus based on flat plate heating vertical strip scanning

Abstract

The application discloses a pulse laser deposition coating equipment based on flat plate heating vertical strip scanning, which comprises a vacuum system, a strip running system, a reciprocating mechanism, a target distance adjusting mechanism, a target running mechanism, a heating mechanism and an optical path system; the application is suitable for the field of coating equipment, through the magnetic powder clutch and the tension sensor closed loop control, the real-time tension is calculated combined with the strip disc ring number and is feedback adjusted, the high-precision control of the strip tension fluctuation and the tension difference fluctuation is realized, the tension difference (Fx) parameter is innovatively introduced, the Fx data is fed back to the PLD system and the water-cooled plate height adjustment is linked, the strip is closely attached to the water-cooled plate, the coating temperature field is stabilized, the thin film deposition uniformity is improved, the three-speed monitoring systems of servo motor driving+strip disc ring number recording+double-side meter counter speed measurement are adopted, the stable control of the strip running speed is realized, and the speed self-diagnosis and meter number self-diagnosis functions are possessed, and the length error and the speed fluctuation in the production process are effectively reduced.

Description

Technical Field

[0001] This invention relates to the field of coating equipment, and more particularly to pulsed laser deposition coating equipment based on flat-plate heating and vertical strip scanning. Background Technology

[0002] YBCO is one of the mainstream high-temperature superconducting materials. Rare earth barium copper oxide (REBCO, where RE represents rare earth elements and YBCO is yttrium-based REBCO material) tapes (i.e., second-generation high-temperature superconducting tapes) have developed into typical multilayer composite structures after more than 30 years of technological development. Second-generation tapes possess advantages such as high superconducting transition temperature, high current carrying capacity, high irreversible field, and inexpensive raw materials, making them one of the key materials for generating strong magnetic fields or for use in strong magnetic field environments. Driven by the demand for fusion magnets, the government attaches great importance to the mass production of superconducting tapes.

[0003] The main technologies for fabricating superconducting layers include pulsed laser deposition (PLD), metal-organic vapor deposition (MOD), reactive co-evaporation (RCE), and metal-organic chemical vapor deposition (MOCVD). PLD, as the mainstream technology for superconducting strip fabrication, is a physical vapor deposition technique performed in a vacuum system. It uses a high-energy pulsed laser beam focused on a target material, causing the surface material to ablate and vaporize, forming a plasma plume that moves towards the baseband, ultimately forming an epitaxial thin film on the baseband surface. Its main working principle typically involves fabricating a superconducting layer with a cubic texture on a flexible metal substrate (usually 50-100 μm thick). First, the baseband with the deposited buffer layer is placed inside the pulsed laser deposition equipment cavity, and then a vacuum is evacuated to a vacuum level of 1 × 10⁻⁶. -4 After Pa, the baseband heating system is activated to heat the baseband to 800-850 degrees Celsius. Then, a certain flow rate of oxygen is introduced into the vacuum chamber. Finally, the laser is activated, and a high-energy pulsed laser beam is focused onto the REBCO superconducting target, causing the target material to be ejected as gaseous plasma and deposited on cerium oxide to form a REBCO superconducting thin film. By controlling process parameters such as the baseband's movement speed, target-substrate distance, laser energy, and frequency, a highly preferentially oriented REBCO superconducting layer of a certain thickness can be obtained.

[0004] Superconducting layer deposition processes based on pulsed laser deposition (PLD) technology mainly include cylindrical and flat-plate heating plate structures, and vertical and parallel strip scanning methods. These four methods can be combined arbitrarily to form superconducting layer deposition processes. However, the "cylindrical heating parallel strip scanning deposition" method is generally not recommended due to its low deposition efficiency and difficulty in forming long areas. Currently, the two main processes used in China are "cylindrical heating plate vertical strip scanning deposition" and "flat-plate heating parallel strip scanning deposition." However, each process has its shortcomings. The former is prone to edge curling after deposition due to uneven strip stress, while the latter requires a precise temperature gradient for the same strip over a short area, making the process unstable. Based on these shortcomings, there is an urgent need to develop and design PLD deposition equipment based on the "flat-plate heating vertical strip scanning deposition" process to overcome the deficiencies of the two aforementioned technologies. Summary of the Invention

[0005] In view of the above problems, the present invention is proposed to provide solutions that overcome or at least partially solve the above problems.

[0006] According to one aspect of the present invention, a pulsed laser deposition coating apparatus based on flat-plate heated vertical strip scanning is provided, comprising a vacuum system, a belt transport system, a reciprocating mechanism, a target distance adjustment mechanism, a target transport mechanism, a heating mechanism, and an optical path system;

[0007] The vacuum system includes an equipment cavity and a main body for the coating process;

[0008] The conveyor system, reciprocating mechanism, target distance adjustment mechanism, target movement mechanism, and heating mechanism are all installed inside the main body of the equipment and are components used to control the movement and heating of the conveyor belt.

[0009] The optical path system is located outside the main body of the device. It uses a lens to introduce laser light into the target inside the main body of the device to form the necessary conditions for coating.

[0010] Preferably, the vacuum system includes a vacuum chamber, a vacuum pump assembly, a valve system, and a vacuum measurement system;

[0011] The vacuum cavity includes a main cavity, and the left ear cavity and the right ear cavity are respectively connected to the two sides of the main cavity;

[0012] The vacuum measurement system is located inside a vacuum cavity, wherein the main cavity is equipped with a resistance gauge, an ionization gauge and a thin film gauge, and the left and right ear cavities are each equipped with a resistance gauge and an ionization gauge;

[0013] The vacuum pump assembly includes a dry pump, a molecular pump, a condenser pump, and a vacuum pipeline. The main chamber, the left ear chamber, and the right ear chamber are all connected to one end of the vacuum pipeline, and the other end of the vacuum pipeline is connected to the dry pump. The main chamber, the left ear chamber, and the right ear chamber are each connected to a molecular pump, and the main chamber is also connected to a condenser pump.

[0014] The valve system includes pneumatic valves installed on each pipeline.

[0015] Preferably, the conveyor system includes a take-up / unload system and a coating reciprocating mechanism; the take-up / unload system includes a take-up / unload strip reel, a magnetic powder clutch, a servo motor, a tension sensor, a meter counter, and an auxiliary guide wheel; the coating reciprocating mechanism is composed of an integrated auxiliary guide wheel, with a retaining edge provided on the auxiliary guide wheel to evenly distribute the strip on the auxiliary guide wheel.

[0016] Preferably, the reciprocating mechanism includes several sets of auxiliary guide wheels. The auxiliary guide wheels are made of stainless steel with a ceramic film coated on the surface. The auxiliary guide wheels are fixed below the coated reciprocating mechanism by a quick-release structure.

[0017] Preferably, the target distance adjustment mechanism includes a handwheel, a lead screw, a lifting seat, a crossbeam, a coating wheel, and a slide rail assembly. The reciprocating mechanism is adjusted by rotating the handwheel to move the heating plate up and down, thereby adjusting the distance between the strip and the ash.

[0018] Preferably, the target-moving mechanism includes an X-axis translational module, a Y-axis translational module, an R-axis rotational module, and a target material water-cooling plate. A target material support plate is installed above the module, and the support plate moves in translational motion under the drive of the module. The coordinated movement of the module along the X, Y, and R axes causes the light source to scan a Z-shaped trajectory on the target surface. The target material water-cooling plate is used to cool the target material during the coating process.

[0019] Preferably, the heating mechanism uses infrared short-wave radiation lamps to irradiate the heating plate, which is divided into main heating and auxiliary heating; the heating plate is provided with several spaced arc surfaces, each arc surface corresponding to one strip, and the number of coatings is selected as needed; several main heating lamps are arranged parallel to the strip direction, and the main heating lamps are straight single tubes; several auxiliary heating lamps are arranged perpendicular to the strip direction, and the auxiliary heating lamps are U-shaped double tubes; temperature detection points are evenly arranged below each main heating lamp on the heating plate.

[0020] Preferably, the optical path system includes a laser, a galvanometer assembly, a reflector assembly, a lens moving mechanism, and a focusing assembly. Multiple incident paths can be achieved by changing the position of the reflector and the working angle of the galvanometer.

[0021] In this invention, a closed-loop control system using a magnetic powder clutch and tension sensor is implemented. Real-time tension is calculated based on the number of strip reels and adjusted accordingly, achieving high-precision control of strip tension fluctuations and tension difference fluctuations. An innovative tension difference (Fx) parameter is introduced, feeding Fx data back to the PLD system and linking it to the water-cooled plate height adjustment. This ensures tight contact between the strip and the water-cooled plate, stabilizing the coating temperature field and improving film deposition uniformity. A triple speed monitoring system—servo motor drive, strip reel count recording, and dual-sided meter counter speed measurement—is employed to achieve stable control of the conveyor speed. This system also features speed and meter count self-diagnosis functions, effectively reducing length errors and speed fluctuations during production. The coating reciprocating mechanism uses an integrated guide wheel and edge guard structure, completely solving the problem of strip slippage on the guide wheel surface, ensuring consistent strip trajectory, and improving the stability of the coating process.

[0022] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the overall structure provided for an embodiment of the present invention;

[0025] Figure 2 A schematic diagram of the vacuum system structure provided in an embodiment of the present invention;

[0026] Figure 3 This is a schematic diagram of the conveyor system structure provided in an embodiment of the present invention;

[0027] Figure 4 This is a schematic diagram of the coating wheel structure provided in an embodiment of the present invention;

[0028] Figure 5 This is a schematic diagram of the reciprocating mechanism structure provided in an embodiment of the present invention;

[0029] Figure 6 This is a schematic diagram of the target distance adjustment mechanism provided in an embodiment of the present invention;

[0030] Figure 7 This is a schematic diagram of the target-moving mechanism provided in an embodiment of the present invention;

[0031] Figure 8 This is a schematic diagram of the heating mechanism structure provided in an embodiment of the present invention;

[0032] Figure 9 This is a schematic diagram of the optical path mechanism provided in an embodiment of the present invention;

[0033] Figure 10 This is a schematic diagram of an optical path that can reverse the aspect ratio of the laser incident spot, provided by an embodiment of the present invention.

[0034] Figure 11 This is a schematic diagram of an optical path that maintains the aspect ratio of the incident laser spot, provided in an embodiment of the present invention.

[0035] Figure 12 A schematic diagram of an optical path that can extend the object distance while simultaneously reversing the aspect ratio of the laser incident spot, provided as an embodiment of the present invention;

[0036] 1. Vacuum system; 11. Main chamber; 12. Left ear canal; 13. Right ear canal; 14. Condensation pump; 15. Molecular pump; 16. Dry pump; 17. Vacuum gauge; 18. Thin-film gauge; 19. Pneumatic valve;

[0037] 2. Belt carrying system; 21. Belt unloading reel; 22. Belt take-up reel; 23. Meter counter wheel; 24. Tension wheel; 25. Guide wheel; 26. First coating wheel; 27. Second coating wheel;

[0038] 3. Reciprocating mechanism; 31. Auxiliary guide wheel;

[0039] 4. Target distance adjustment mechanism; 41. Crossbeam; 42. Slide rail; 43. Lifting seat; 44. Lead screw; 45. Handwheel; 46. Coating wheel;

[0040] 5. Target movement mechanism; 51. X-axis translational module; 52. Y-axis translational module; 53. R-axis rotational module; 54. Target material water-cooling plate;

[0041] 6. Heating mechanism; 61. Upper cooling wall; 62. Lower cooling wall; 63. Heating lamp; 64. Cooling water pipe;

[0042] 7. Optical path system; 71. Laser; 72. Mirror; 73. Galvanometer. Detailed Implementation

[0043] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0044] The terms "comprising" and "having," and any variations thereof, in the specification, embodiments, claims, and drawings of this invention are intended to cover non-exclusive inclusion, such as including a series of steps or units.

[0045] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0046] Pulsed laser deposition equipment based on flat-panel heating and vertical strip scanning, such as Figure 1 As shown, it includes a vacuum system, a conveyor belt system 2, a reciprocating mechanism, a target distance adjustment mechanism, a target movement mechanism, a heating mechanism, and an optical path system 7;

[0047] The vacuum system includes an equipment cavity and a main body for the coating process;

[0048] The conveyor system 2, reciprocating mechanism, target distance adjustment mechanism, target movement mechanism, and heating mechanism are all installed inside the main body of the equipment and are components used to control the movement and heating of the conveyor belt.

[0049] The optical path system 7 is located outside the main body of the device, and it is a necessary condition for introducing laser light into the target inside the main body of the device through a lens to form a coating.

[0050] Furthermore, the optical path system 7 is located on the rear side of the main cavity 11, and the laser 71 is located on the left side of the optical path system 7.

[0051] In one possible implementation, such as Figure 2 As shown, the vacuum system includes a vacuum chamber, a vacuum pump assembly, a valve system, and a vacuum measurement system.

[0052] The vacuum cavity includes a main cavity 11, and the left ear cavity 12 and the right ear cavity 13 are respectively connected to the two sides of the main cavity 11.

[0053] The vacuum measurement system is located inside the vacuum chamber, wherein the main chamber 11 is equipped with a resistance gauge, an ionization gauge and a thin film gauge 18, and the left ear cavity 12 and the right ear cavity 13 are each equipped with a resistance gauge and an ionization gauge;

[0054] The vacuum pump assembly includes a dry pump 16, a molecular pump 15, a condenser pump 14, and a vacuum pipeline. The main chamber 11, the left ear chamber 12, and the right ear chamber 13 are all connected to one end of the vacuum pipeline, and the other end of the vacuum pipeline is connected to the dry pump 16. The main chamber 11, the left ear chamber 12, and the right ear chamber 13 are respectively connected to the molecular pump 15. The main chamber is also connected to the condenser pump 14. Vacuum gauges 17 are provided on the main chamber 11, the left ear chamber 12, and the right ear chamber 13.

[0055] The valve system includes pneumatic valves 19 installed on each pipeline.

[0056] In one possible implementation, such as Figure 3 As shown, the conveyor system 2 includes a take-up / feed system and a coating reciprocating mechanism; the take-up / feed system includes a take-up / feed strip reel, a tension adjustment device, a servo motor, a tension sensor, a meter counter and an auxiliary guide wheel; the coating reciprocating mechanism is composed of an integrated auxiliary guide wheel, with a retaining edge set on the auxiliary guide wheel to evenly distribute the strip on the auxiliary guide wheel.

[0057] Furthermore, a tape release reel 21 is provided at the center of the left ear cavity 12; a tape take-up reel 22 is provided at the center of the right ear cavity 13; the tape take-up reel 22 is driven by a servo motor, and a measuring wheel 23 and a tension wheel 24 are respectively provided on the inner and outer sides of the lower end of the left ear cavity 12 and the right ear cavity 13. A measuring device is provided on one side of the measuring wheel 23. Guide wheels 25 are provided on both sides of the upper end of the main cavity 11, the left ear cavity 12 and the right ear cavity 13. The tape is led out from the tape release reel 21, along the measuring wheel 23, the tension wheel 24 and the two guide wheels 25 on the left ear cavity 12, passes the left guide wheel 25 of the main cavity 11 and wraps around to the right side of the first coating wheel 26, then from the lower side of the first coating wheel 26 to the left side of the second coating wheel 27, then from the upper side of the second coating wheel 27 to the right guide wheel 25 of the main cavity 11, and finally passes through the two guide wheels 25, the tension wheel 24 and the measuring wheel 23 of the right ear cavity 13 and enters the tape take-up reel 22.

[0058] Furthermore, the strip is repeatedly wound between the first coating wheel 26 and the second coating wheel 27. Several positioning grooves are provided on the lower side of the first coating wheel 26 winding towards the second coating wheel 27, and the strip is stuck in the positioning grooves.

[0059] In one possible implementation, such as Figures 4-5 As shown, the reciprocating mechanism 3 includes several sets of auxiliary guide wheels 31. The auxiliary guide wheels 31 are stainless steel single-sided wheels (coated with ceramic film on the surface). The auxiliary guide wheels 31 are fixed to the bottom of the coated reciprocating mechanism through a quick-release structure.

[0060] Furthermore, there are two auxiliary guide wheels 31. The upper end of the auxiliary guide wheel 31 is connected to the mounting plate by a tenon and mortise sliding connection structure and is positioned by bolts.

[0061] Furthermore, compared to existing technologies, two sets of auxiliary guide rollers 31 are added to adjust the different heights of the strip; a set of stabilizing guide rollers is added before each of the auxiliary guide rollers 31 of the reciprocating mechanism 3, where tension gauges are still present, but closer to the tension center for more accurate detection values; the reciprocating rollers are parallel, which determines the different laser scanning methods; the lifting mechanism is simplified to a gearless design based on functional practical needs; the two sets of reciprocating auxiliary guide rollers only serve the function of conveying the strip, eliminating the heating function; the heating mechanism does not act as a guide roller; a strip cooling device is added before the strip is received into the right reel.

[0062] In one possible implementation, such as Figure 6As shown, the target distance adjustment mechanism 4 consists of a handwheel 45, a lead screw 44, a lifting seat 43, a crossbeam 41, a coating wheel 46, and a slide rail 42. The reciprocating mechanism is adjusted by rotating the handwheel to move the heating plate up and down, mainly adjusting the distance between the strip and the ash.

[0063] Furthermore, there are two crossbeams 41, both ends of which are connected to the column via slide rails 42 to realize the lifting and lowering adjustment of the crossbeams 41. The first coating wheel 26 and the second coating wheel 27 are both located between the two crossbeams 41. The lifting seat 43 is located above the crossbeams 41. The lead screw 44 is screwed to the top of the lifting seat 43. The handwheel 45 is located at the upper end of the lead screw 44. A pressure plate is located below the lead screw 44 for adjusting the distance between the strip and the ash.

[0064] In one possible implementation, such as Figure 7 As shown, the target-following mechanism 5 includes an X-axis translational module 51, a Y-axis translational module 52, an R-axis rotational module 53, and a target material water-cooling plate 54. A target material support plate is mounted above the modules, and the support plate moves in a translational motion driven by the modules. The coordinated movement of the modules along the X, Y, and R axes causes the light source to scan the target surface in a Z-shaped, serpentine, or spiral trajectory. The target material water-cooling plate can cool the target material during the coating process.

[0065] Furthermore, the X-axis translation module 51, Y-axis translation module 52, R-axis rotation module 53, and target material water-cooled plate 54 are all applications of existing technologies, and will not be specifically described here.

[0066] In one possible implementation, such as Figure 8 As shown, the heating mechanism 6 uses infrared short-wave radiation lamps to irradiate the heating plate, which is divided into main heating and auxiliary heating. The heating plate is set with spaced arc surfaces, each arc surface corresponding to one strip, and the number of coatings is selected as needed. The main heating lamps are arranged parallel to the strip direction and are straight single tubes. The auxiliary heating lamps are arranged perpendicular to the strip direction and are U-shaped double tubes. Temperature detection points are evenly arranged below each main heating lamp on the heating plate.

[0067] Furthermore, the laser from laser 71 is introduced into the target inside the main body of the device via three reflectors 72 and galvanometer 73 to form a coating, which is a necessary condition.

[0068] Furthermore, an upper cooling wall 61 and a lower cooling wall 62 are respectively provided on the upper and lower sides of the heating mechanism 6, and the heating lamp tube 63 is located inside them. Both the upper cooling wall 61 and the lower cooling wall 62 are connected to the cooling water pipe 64.

[0069] In one possible implementation, such as Figure 9 - Figure 12As shown, the optical path system 7 mainly consists of a laser 71, a galvanometer assembly, a reflector assembly, a lens moving mechanism, and a focusing assembly. To obtain the required light source path and spot size, appropriate object distance adjustment and multi-level reflection imaging are necessary. Depending on different process requirements, multiple incident paths can be achieved by changing the position of the reflector and the working angle of the galvanometer.

[0070] In one possible implementation, the product structure is as follows:

[0071] (a) The belt conveyor mechanism includes: two independent winding and unwinding systems, a reciprocating mechanism, an encoder, a tension meter, and guide rollers.

[0072] Each independent take-up and unwind system includes a rotary motor, a tension adjustment device, a coupling, a magnetohydrodynamic seal, and a strip reel. These components are cascaded together via a shaft, enabling both take-up and unwinding at a given tension and speed.

[0073] Magnetofluidic seals are used for rotary sealing between the chamber body and the shaft. The roll-to-roll multi-channel reciprocating mechanism has several independent guide pulleys on both sides. The base strip is pulled from the strip reel of the left take-up / unwind system and wound into the strip reel of the right take-up / unwind system via the roll-to-roll reciprocating structure. Along the way, it is guided by three guide wheels, an encoder, a tension sensor, and after entering the main chamber, it is guided by a tension wheel, the left and right guide wheels of the reciprocating mechanism, a flat heating mechanism, and a strip cooling mechanism. The guide pulleys are in close contact with the base strip surface, and the distance, tension, and linear speed of the base strip are measured. Real-time feedback control of the distance, tension, and linear speed allows the rotary motor and tension adjustment device to maintain constant tension and constant linear speed while the strip is heated on one side, and the direction of travel can be selected.

[0074] Tension control:

[0075] 1) By using a tension adjustment device and a tension sensor, stable tension control is achieved, thereby achieving stable control of the tension difference between the left and right ear cavities;

[0076] 2) By recording the number of strip reels, calculate the radius of the strip reel, calculate the strip tension in real time, and feed it back to the tension adjustment device to regulate the tension;

[0077] 3) Set Fx = right tension value - left tension value. Fx fluctuation should be less than 5%. Fx data is fed back to the PLD, and in conjunction with water-cooled plate height adjustment, stable Fx control is achieved. Stable tension difference control ensures stable bonding between the strip and the water-cooled plate, stabilizes the coating temperature, and improves coating quality. Through the above adjustments, constant tension control is achieved, with fluctuations better than 3%; tension difference fluctuations are better than 5%.

[0078] Belt speed control:

[0079] By controlling the rotation speed with a servo motor, combined with recording the number of strip reel rotations and measuring the speed with left and right meter counters, stable control of the conveyor belt speed is achieved. Simultaneously, the system can perform self-diagnosis of the strip reel speed and meter count, promptly detecting and correcting speed deviations, reducing production errors, and improving production accuracy.

[0080] Coating reciprocating mechanism:

[0081] The coating reciprocating mechanism adopts an integrated guide wheel design, ensuring uniform rotation of the strip on the guide wheels. This effectively reduces strip slippage on the guide wheel surface, improving the stability and uniformity of the coating process. (See appendix for details) Figure 10 ).

[0082] (ii) The target distance adjustment mechanism includes: handwheel, trapezoidal lead screw, connecting seat, and linear slide rail;

[0083] The distance between the strip and the target material is adjusted by simply pulling the reciprocating mechanism beam with a handwheel, which moves it up and down via a linear slide rail. This invention optimizes the lifting mechanism based on functional and practical requirements, simplifying it into a gearless design, eliminating the need for complex structural designs such as bellows, teeth, chains, and motors.

[0084] Target distance adjustment:

[0085] The target-tracking system includes a target material, a target holder, X and Y axis modules, an R-axis rotary table, and a target distance adjustment mechanism. The target holder carries the target material, and the X and Y axis modules and R-axis rotary table connected to the target holder drive its translation and rotation. The target distance adjustment mechanism adjusts the distance between the target holder and the baseband flat against the heating plate. The target material can be adjusted not only vertically but also horizontally during the coating process via a handle on the outside of the cavity, facilitating precise control of the coating process. The distance between the baseband and the target material is adjustable, as is the angle between the incident laser and the target plane, to meet different coating requirements.

[0086] Water-cooling design:

[0087] The strip is equipped with an arc-shaped water-cooled plate, which is adjustable up and down to adjust the contact surface between the strip and the feather, ensuring uniform coating. The distance between the center of the target and the coating area of ​​the strip is adjustable, as is the angle between the laser and the target plane, enabling precise etching. This design reduces the temperature rise of the motor surface, allowing the X and Y axis motors of the module to move within the cavity without needing to feed through the main cavity, reducing the need for a sealing hole and minimizing the risk of leakage. Simultaneously, this function reduces the temperature of the target, resulting in more uniform etching.

[0088] (III) The heating plate has a flat structure with multiple grooves on its bottom surface. These grooves are evenly spaced on the lower arc surface of the heating plate, and contact surfaces for the superconducting tape are located between adjacent grooves. These contact surfaces are arranged side-by-side. The contact surfaces are arc-shaped, and their width matches the width of the superconducting tape. An auxiliary guide wheel allows for fine adjustment of the contact distance between the tape and the heating plate. The heating plate and the superconducting tape move through friction. To prevent the tape from sliding and colliding with each other, causing mechanical damage, the multiple reciprocating tape tracks are spaced apart. Multiple main heating lamps and auxiliary heating lamps are installed inside the heating plate, heating the base tape attached to the heating plate through conduction. Flat plate heating allows for temperature gradient settings along the lamp arrangement direction, using a separate power supply to control each lamp, eliminating the need for segmented power designs for each lamp. This simplifies the design, saves costs, and reduces control complexity. An opening in the cooling wall on the outer side of the heating plate allows the pulsed laser beam to pass through and strike the target surface. The heating plate is connected to the reciprocating mechanism beam via a fixing block, with zirconia ceramic gaskets providing insulation between the fixing block and the beam to reduce heat loss. The fixing block and beam are secured with simple bolts, keeping the heating plate stationary and eliminating the need for rotating or moving bearings, thus simplifying the design.

[0089] Temperature control of coated strip:

[0090] Strip temperature control consists of two parts:

[0091] 1) Strip tension control: By controlling constant tension and constant tension difference, the strip is kept in close contact with the surface of the water-cooled plate, ensuring sufficient heat exchange between the strip and the water-cooled plate and maintaining stable strip temperature.

[0092] 2) Water-cooled plate temperature control: By monitoring the temperature of the water-cooled plate and adjusting the chilled water flow rate using PID control, the temperature of the water-cooled plate can be precisely controlled, thereby ensuring the temperature stability of the strip.

[0093] (iv) The vacuum measurement system of the vacuum system is configured as follows: one resistance gauge and one ionization gauge are installed in each of the left ear cavity 12 and the right ear cavity 13, and one resistance gauge, one ionization gauge and one thin-film gauge are installed in the main cavity 11. The detection data of each vacuum gauge is fed back to the valve system in real time. The pumping speed is controlled by adjusting the opening of the pneumatic valve to maintain a gradient vacuum environment and prevent gas from diffusing from the ear cavity to the main cavity 11. By configuring differentiated vacuum measuring instruments for each cavity (resistance gauge + ionization gauge in the ear cavity, and thin-film gauge added to the main cavity 11), the vacuum degree of each cavity can be monitored accurately in real time. The monitoring data is fed back to the pneumatic valve system. The pumping speed is dynamically adjusted by adjusting the valve opening to make the vacuum degree of the ear cavity higher than that of the main cavity 11, forming a gradient vacuum environment of ≤0.005Pa in the ear cavity + 0.01~0.04Pa in the main cavity, thus blocking the gas diffusion path. It completely solves the problem of gas diffusion from the ear cavity into the coating main cavity 11, providing a stable and pure vacuum environment for the coating process of the main cavity 11; it avoids excessive impurities in the film layer caused by vacuum fluctuations, significantly improving the purity and density of the YBCO film layer; multi-gauge combined monitoring and valve linkage control ensure that the vacuum level is stable within the set range for a long time, improves process repeatability, and reduces product defect rate.

[0094] Vacuum system:

[0095] It can maintain the vacuum level in the coating area between 0.01 and 0.04 Pa, while ensuring that the vacuum level in the ear cavity is better than 0.005 Pa, effectively preventing the diffusion of gas from the ear cavity into the main cavity and providing a stable vacuum environment for the coating process.

[0096] (v) Optical path system:

[0097] The optical path system includes a laser 71, a galvanometer assembly, a reflector assembly, a lens moving mechanism, and a focusing assembly. The reflector assembly allows for fine-tuning of the lens along the four axes: X, Y, Z, and θ.

[0098] To obtain the required spot size, three paths were designed to satisfy multi-level reflection imaging and matching object distance adjustment;

[0099] Option 1 can achieve a reversal of the aspect ratio of the laser incident spot;

[0100] Option 2 can maintain the aspect ratio of the laser incident spot unchanged;

[0101] Option 3 can lengthen the object distance while simultaneously reversing the aspect ratio of the laser incident spot.

[0102] (vi) Strip inspection:

[0103] A CCD industrial camera is installed in the ear cavity to achieve real-time visual inspection of the strip surface quality, promptly detect defects on the strip surface, and accurately record the location of defects, providing a basis for subsequent quality analysis and process improvement.

[0104] Beneficial effects:

[0105] (1) Innovation in precise tension control:

[0106] 1) Multi-dimensional tension control mechanism: Through the closed-loop control of tension adjustment device and tension sensor, combined with the number of strip coils to calculate real-time tension and provide feedback adjustment, high-precision control with strip tension fluctuation better than 3% and tension difference fluctuation better than 5% is achieved, solving the coating quality problem caused by the instability of traditional tension control.

[0107] 2) Tension difference linkage control: The tension difference (Fx) parameter is innovatively introduced, and the Fx data is fed back to the PLD system and linked to the water cooling plate height adjustment to ensure that the strip and the water cooling plate are tightly attached, stabilize the coating temperature field, and improve the uniformity of film deposition.

[0108] (2) Intelligent innovation of conveyor belt system

[0109] 1) Speed ​​self-diagnosis and error compensation: The triple speed monitoring system of servo motor drive + strip reel count recording + double-sided meter counter speed measurement is adopted to achieve stable control of the belt speed, and has speed self-diagnosis and meter count self-diagnosis functions, effectively reducing length error and speed fluctuation in the production process.

[0110] 2) Integrated guide wheel design: The coating reciprocating mechanism adopts an integrated guide wheel + side guard structure, which completely solves the problem of strip sliding on the guide wheel surface, ensures the consistency of strip running trajectory, and improves the stability of coating process.

[0111] 3) Auxiliary guide wheel design: adjustable strip height; each reciprocating mechanism guide wheel has a set of stabilizing guide wheels in front of it, where tension gauges are still located, closer to the tension center for more accurate readings; the reciprocating wheels are parallel, which determines the different laser scanning methods; simplified design, no gearbox; a strip cooling device is added before the strip is received into the right reel.

[0112] (3) Target distance adjustment mechanism: Compared with the traditional one, it is completely simplified, eliminating the cumbersome structural design of bellows, gears, chains, motors and other parts, and achieving the same function.

[0113] (4) Innovation in gradient control of vacuum environment

[0114] Flat-plate heating is simpler than cylindrical structures; it allows for a wider coating area; it offers better strip tension consistency; and the fixing structure is completely different. The fixing block and crossbeam are fastened together with simple bolts, and the heating plate is fixed, requiring no rotation or movement, thus eliminating the need for special structures such as rolling bearings. The structure is much simpler in comparison.

[0115] (5) Innovation in online detection and process control

[0116] The composite temperature control adopts a dual mode of "tension bonding heat exchange + water-cooled plate PID temperature control". Constant tension ensures full contact between the strip and the water-cooled plate, and combined with dynamic adjustment of chilled water flow, it achieves high-precision control of strip coating temperature within ±5℃.

[0117] (6) Temperature control

[0118] Temperature gradients are set along the arrangement of the flat heating lamps, and each lamp is controlled by a separate power supply, eliminating the need for segmented power designs for each lamp. This simplifies the design, saves costs, and reduces control complexity.

[0119] (7) Design of heating plate

[0120] The curved groove design of the heating plate improves the utilization rate of the heat sink compared to the groove design on a cylindrical surface. The protective grate inside the groove of the heating plate reduces the corrosion of the coating on the heating plate and makes disassembly and cleaning simple and convenient.

[0121] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A pulsed laser deposition coating equipment based on flat-plate heating and vertical strip scanning, characterized in that, This includes a vacuum system, a conveyor system, a reciprocating mechanism, a target distance adjustment mechanism, a target movement mechanism, a heating mechanism, and an optical path system. The vacuum system includes an equipment cavity and a main body for the coating process; The conveyor system, reciprocating mechanism, target distance adjustment mechanism, target movement mechanism, and heating mechanism are all installed inside the main body of the equipment and are components used to control the movement and heating of the conveyor belt. The optical path system is located outside the main body of the equipment. It uses a lens to introduce laser light into the target inside the main body of the equipment to form the necessary conditions for coating. The conveyor system includes a take-up / unload system and a coating reciprocating mechanism; the take-up / unload system consists of a take-up / unload strip reel, a magnetic powder clutch, a servo motor, a tension sensor, a meter counter, and an auxiliary guide wheel; the coating reciprocating mechanism consists of an integrated auxiliary guide wheel with a retaining edge on it, which evenly distributes the strip on the auxiliary guide wheel.

2. The pulsed laser deposition equipment based on flat-plate heating and vertical strip scanning as described in claim 1, characterized in that: The vacuum system includes a vacuum chamber, a vacuum pump assembly, a valve system, and a vacuum measurement system; The vacuum cavity includes a main cavity, and the left ear cavity and the right ear cavity are respectively connected to the two sides of the main cavity; The vacuum measurement system is located inside a vacuum cavity, wherein the main cavity is equipped with a resistance gauge, an ionization gauge and a thin film gauge, and the left and right ear cavities are each equipped with a resistance gauge and an ionization gauge; The vacuum pump assembly includes a dry pump, a molecular pump, a condenser pump, and a vacuum pipeline. The main chamber, the left ear chamber, and the right ear chamber are all connected to one end of the vacuum pipeline, and the other end of the vacuum pipeline is connected to the dry pump. The main chamber, the left ear chamber, and the right ear chamber are each connected to a molecular pump, and the main chamber is also connected to a condenser pump. The valve system includes pneumatic valves installed on each pipeline.

3. The pulsed laser deposition equipment based on flat-plate heating and vertical strip scanning as described in claim 1, characterized in that: The reciprocating mechanism includes several sets of auxiliary guide wheels. The auxiliary guide wheels are made of stainless steel with a ceramic film coated on the surface. The auxiliary guide wheels are fixed to the bottom of the coated reciprocating mechanism through a quick-release structure.

4. The pulsed laser deposition equipment based on flat-plate heating and vertical strip scanning as described in claim 1, characterized in that: The target distance adjustment mechanism includes a handwheel, a lead screw, a lifting seat, a crossbeam, a coating wheel, and a slide rail assembly. By rotating the handwheel, the reciprocating mechanism is adjusted to move the heating plate up and down, thereby adjusting the distance between the strip and the ash.

5. The pulsed laser deposition equipment based on flat-plate heating and vertical strip scanning as described in claim 1, characterized in that: The target-moving mechanism includes an X-axis translational module, a Y-axis translational module, an R-axis rotational module, and a target material water-cooling plate. A target material support plate is installed above the module. The support plate moves in translational motion under the drive of the module. The coordinated movement of the module along the X, Y, and R axes causes the light source to scan a Z-shaped trajectory on the target surface. The target material water-cooling plate is used to cool the temperature rise of the target material during the coating process.

6. The pulsed laser deposition equipment based on flat-plate heating and vertical strip scanning as described in claim 1, characterized in that: The heating mechanism uses infrared short-wave radiation lamps to irradiate the heating plate, and is divided into main heating and auxiliary heating. The heating plate has several spaced arc surfaces, each arc surface corresponding to one strip, and the number of coatings is selected as needed. Several main heating lamps are arranged parallel to the strip direction, and the main heating lamps are straight single tubes. Several auxiliary heating lamps are arranged perpendicular to the strip direction, and the auxiliary heating lamps are U-shaped double tubes. Temperature detection points are evenly arranged below each main heating lamp on the heating plate.

7. The pulsed laser deposition equipment based on flat-plate heating and vertical strip scanning as described in claim 1, characterized in that: The optical path system includes a laser, a galvanometer assembly, a reflector assembly, a lens moving mechanism, and a focusing assembly. Multiple incident paths can be achieved by changing the position of the reflector and the working angle of the galvanometer.

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