Method for realizing crucible material supplementation of electron beam evaporation equipment without destroying vacuum

Abstract

The invention discloses a method capable of realizing material supplement of a crucible of electron beam evaporation equipment without destroying vacuum, relates to the technical field of superconducting quantum computing, remarkably improves production efficiency, and solves the problem that the conventional electron beam evaporation equipment cannot realize material supplement when crucible raw materials are used up and material supplement is needed. In the prior art, the vacuum environment of a coating cavity is often damaged, the process of re-vacuumizing is extremely time-consuming, and the equipment is in an idle state for a long time, however, according to the method, by means of the unique design of the upper crucible and the lower crucible and the cooperation of the telescopic mechanical arm, the sliding rail and the lining plate, crucible reloading can be completed on the premise that vacuum is not damaged, and the production efficiency is improved. Therefore, the coating process can be continuously carried out, frequent interruption and waiting for re-vacuumizing are not needed, the overall production period is greatly shortened, the equipment can complete more film evaporation tasks in unit time, the output of industrial production is effectively improved, and higher economic benefits are brought to enterprises.

Description

Technical Field

[0001] The present invention relates to the technical field of superconducting quantum computing, and specifically provides a method for replenishing the crucible of an electron beam evaporation device without destroying the vacuum. Background Art

[0002] The high-vacuum electron beam evaporation system is a very mature and dominant coating method in vacuum coating technology. Its working principle is as follows: In a vacuum environment, with the cooperation of electromagnetic fields, high-energy electrons are used to bombard the target material (i.e., the evaporation material) in the crucible, causing it to evaporate and gasify. Then, it is transported to the substrate and condensed and deposited on the substrate to form a thin film.

[0003] However, the number of crucibles in the coating chamber is small, usually 4 to 6, and the capacity of each crucible is 20 cc. The maximum thickness of the thin film that can be evaporated by a single crucible is 300 nm, which cannot meet the requirements of substrates that need to be coated with thicker thin films. When facing substrates that need to be coated with thicker thin films, multiple coatings are required, which requires opening the chamber for material replacement. The conventional process for material replacement is to first fill the coating chamber with nitrogen until it reaches atmospheric pressure, then open the chamber, remove the crucible for material replacement. However, the working pressure of this equipment during coating requires an ultra-high vacuum level, which not only increases the time for the equipment to recover the vacuum but also has a certain impact on the film layer of the substrate.

[0004] Therefore, a method for replenishing the crucible of an electron beam evaporation device without destroying the vacuum degree is proposed to meet the requirements of substrates that need to be coated with thicker thin films. Summary of the Invention

[0005] The purpose of the present invention is to make up for the deficiencies of the prior art and provide a method for replenishing the crucible of an electron beam evaporation device without destroying the vacuum. This method designs the crucible of the evaporation source of the electron beam evaporation coating device into a double-layer mode, uses a telescopic robotic arm to assist in the lifting operation of the crucible, and also sets a sliding track for the movement of the crucible and a lining plate to support the movement of the crucible, realizing crucible replacement without destroying the vacuum state of the coating chamber, and thus being able to continue thin film evaporation.

[0006] To solve the above technical problems, the present invention provides the following technical solution: A method for replenishing the crucible of an electron beam evaporation device without destroying the vacuum, and the specific steps of this method are as follows:

[0007] S100: Design the crucible of the electron beam evaporation device into an upper and lower double-layer structure, where the upper crucible is used for evaporation raw materials, the lower crucible serves as a spare raw material storage bin, and an electric slide rail system that can precisely control displacement is installed in the coating cavity;

[0008] S200: Set the threshold of the remaining raw material. When the remaining raw material monitoring sensor detects that the remaining raw material in the upper crucible is close to the threshold, start the robotic arm in the electric slide rail system to descend along the longitudinal slide rail, translate the upper crucible from the evaporation position along the transverse slide rail to the transfer area above the lower crucible, and the robotic arm releases the upper crucible to make it fall onto the buffer lining on the top of the lower crucible. The elastic coefficient of the buffer lining is calculated and determined according to the weight and descending speed of the upper crucible. The calculation process is as follows: Where K is the elastic coefficient of the buffer pad, m is the mass of the upper crucible, v is the instantaneous descending speed when the robotic arm releases the upper crucible, and Δh is the maximum allowable compression of the buffer pad. The mass m of the upper crucible is obtained by pre-weighing the crucible and storing it in the equipment control system. The instantaneous descending speed v is obtained by fitting the rotational speed of the robotic arm motor and the transmission ratio;

[0009] S300: Move the upper crucible filled with new raw material from the raw material loading area outside the coating chamber to above the transfer area along the transverse slide rail through the electric slide rail system, and the robotic arm descends along the longitudinal slide rail to grab the new upper crucible;

[0010] S400: The robotic arm carries the new upper crucible to rise along the longitudinal slide rail and translate along the transverse slide rail to the evaporation position;

[0011] S500: Adjust the parameters of the electron beam evaporation equipment and continue the thin film evaporation operation. During the whole process, the vacuum pressure in the coating chamber is monitored in real time through a pressure sensor. When the pressure shows abnormal fluctuations, start the vacuum compensation algorithm for adjustment. The formula of the vacuum compensation algorithm is: Where P comp is the vacuum compensation pressure value, P set is the preset vacuum pressure value, P act is the actually monitored vacuum pressure value, P prev is the actually monitored vacuum pressure value at the previous moment, k p 、k i 、k d are the proportional, integral, and differential coefficients respectively, Δt is the time interval, t0 is the starting time, and t is the current time.

[0012] Furthermore, the electric slide rail system includes a transverse slide rail and a longitudinal slide rail. The transverse slide rail and the longitudinal slide rail are perpendicular to each other and connected. A robotic arm that can move up and down along the longitudinal slide rail is arranged on the longitudinal slide rail, and a crucible clamping device is arranged at the end of the robotic arm;

[0013] At the same time, a pressure sensor and a remaining raw material monitoring sensor are arranged in the coating chamber. The pressure sensor is used to monitor the change of the vacuum pressure in the coating chamber, and the remaining raw material monitoring sensor is used to monitor the remaining raw material in the upper crucible.

[0014] Further, the crucible clamping device of the robotic arm includes multiple adjustable jaws. A pressure sensing sheet is provided inside the jaws, and the pressure sensing sheet is connected to the equipment control system. When the robotic arm grabs the crucible, the pressure sensing sheet detects the pressure between the jaws and the crucible, and the equipment control system adjusts the clamping force of the jaws according to the pressure value. The specific adjustment is as follows: F adj = F init + k f × (P s - P t ), where F adj is the adjusted clamping force, F init is the initial clamping force setting value, k f is the pressure adjustment coefficient, P s is the actual value of the pressure sensing sheet, P t is the target pressure value.

[0015] Further, the horizontal slide rail and the vertical slide rail in the electric slide rail system adopt magnetic levitation drive technology, and the driving magnetic field intensity is determined according to the overall weight of the crucible and the robotic arm: where B is the driving magnetic field intensity, m total is the total mass of the crucible and the robotic arm, g is the acceleration due to gravity, μ0 is the vacuum permeability, N is the number of turns of the magnetic levitation coil, I is the coil current, and L is the length of the magnetic levitation track.

[0016] Further, a temperature sensor is provided inside the buffer lining at the top of the lower crucible. After the upper crucible falls onto the buffer lining, the temperature sensor detects the temperature change of the buffer lining. When the temperature is too high, the cooling system is started to cool the buffer pad. The cooling power of the cooling system is determined according to the temperature increase amplitude of the buffer pad and the specific heat capacity of the buffer pad material: where P cool is the cooling power, c is the specific heat capacity of the buffer pad material, m pad is the mass of the buffer pad, ΔT is the temperature increase value of the buffer pad, and Δt cool is the cooling time.

[0017] Further, a raw material pretreatment device is provided in the raw material loading area. Before the new raw material is loaded into the upper crucible, the raw material pretreatment device preprocesses the raw material, including crushing, screening, and mixing. The degree of raw material crushing is determined according to the particle size of the raw material for the electron beam evaporation process: D crush = k c × D evap , where D crush is the maximum particle diameter of the crushed raw material, k c is the crushing coefficient, and D evapis the optimal particle diameter of the raw material for electron beam evaporation. The screening uses a multi-layer sieve structure, and the sieve aperture is determined according to the crushing degree. The stirring speed and time are determined according to the raw material characteristics and mixing uniformity: v mix = k m × ρ mix × V crucible , where v mix is the stirring speed, k m is the stirring coefficient, ρ mix is the average density of the mixed raw materials, V crucible is the volume of the upper crucible, t mix is the stirring time, k t is the time coefficient, Q mix is the flow rate of the stirring device.

[0018] Furthermore, the motion trajectory planning of the robotic arm adopts an artificial intelligence optimization algorithm, with the total motion time of the robotic arm from grasping the upper crucible to moving it to the evaporation position being the shortest and the energy consumption during the motion process being the lowest as the objective function. The objective function expression is J = w t × T + w e × E, where J is the comprehensive objective value, w t is the time weight coefficient, w e is the energy weight coefficient, T is the total motion time, E is the total energy consumption, and the motion control of the robotic arm is realized through the artificial intelligence optimization algorithm.

[0019] Compared with the prior art, the method for replenishing the crucible of an electron beam evaporation device without destroying the vacuum has the following beneficial effects:

[0020] First, the method for replenishing the crucible of an electron beam evaporation device without destroying the vacuum involved in the present invention significantly improves production efficiency. When the raw material in the crucible of a traditional electron beam evaporation device is exhausted and needs to be replenished, the vacuum environment of the coating chamber often has to be destroyed, and then the process of re-pumping vacuum is extremely time-consuming, making the device idle for a long time. However, with this method, through the coordinated cooperation of its unique upper and lower double crucible design, retractable robotic arm, sliding track, and lining plate, it can complete crucible replacement without destroying the vacuum, which means that the coating process can be carried out continuously without frequent interruption waiting for re-pumping vacuum, greatly shortening the overall production cycle, enabling the device to complete more thin film evaporation tasks per unit time, effectively increasing the output of industrial production, and bringing higher economic benefits to the enterprise.

[0021] Second, this method plays a positive role in improving the film quality. In the traditional operation of breaking vacuum and replenishing materials, the subtle changes in the environment inside the coating chamber after re-evacuating may affect the quality indicators such as the uniformity and stability of the film. However, this method maintains the coating chamber in a stable vacuum state all the time, avoiding various unstable factors caused by frequent vacuum breaking. At the same time, through the precise control of the telescopic robotic arm, the high-precision sliding track ensures the stable movement of the crucible, and the intelligent adaptive liner provides a stable supporting force design, ensuring that during the material replenishment and subsequent evaporation process, the evaporation of the raw materials by the electron beam is more uniform and stable, making the thickness of the coated film more uniform and the quality more reliable.

[0022] Other advantages, objectives, and features of the present invention will be described to some extent in the subsequent specification, and to some extent, will be obvious to those skilled in the art based on the study of the following text, or can be taught from the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0024] Figure 1 It is a plan view of a method for realizing crucible replenishment of an electron beam evaporation device without breaking vacuum;

[0025] Figure 2 It is a perspective view of a double-layer crucible of a method for realizing crucible replenishment of an electron beam evaporation device without breaking vacuum;

[0026] Figure 3 It is a motion process diagram of the crucible and the robotic arm in a method for realizing crucible replenishment of an electron beam evaporation device without breaking vacuum.

[0027] In the figures: 1 is the substrate for film deposition, 2 is the electron gun of the electron beam evaporation device, 3 and 4 are the acceleration electrode and the electron beam respectively, 5 is the platform for placing the crucible and rotating, 6 is the cooling water, 7 is the scattered electrons, 8 is the collector of the scattered electrons, a is the front view of the platform for placing the crucible and rotating, b is the top view of the platform for placing the crucible and rotating, c is the left view of the platform for placing the crucible and rotating, 9 is the telescopic robotic arm, 10 is the sliding track, and 11 is the liner. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0029] Embodiment 1

[0030] This embodiment elaborates in detail the process of single-layer metal thin film evaporation by using a method of replenishing the crucible of an electron beam evaporation device without destroying the vacuum. By constructing an electron beam evaporation device with a special structure, including an upper and lower double-layer crucible, an electric slide rail system, and a variety of sensors, the evaporation operation of metal raw materials is carried out. During the evaporation process, the crucible material replacement process is accurately controlled based on the monitoring of the remaining amount of raw materials. The seamless connection is achieved by means of a telescopic robotic arm, a sliding track, and a buffer lining, and the vacuum pressure is adjusted by an algorithm to ensure that the thin film evaporation continues in a stable vacuum environment. Finally, a high-quality, uniform-thickness single-layer metal thin film is obtained, fully demonstrating the excellent performance of this invention in improving production efficiency and thin film quality.

[0031] In specific implementation, first, an electron beam evaporation device is constructed. The upper and lower double-layer crucibles are accurately installed in the coating cavity, and the electron beam evaporation device is accurately started. According to the characteristics of the metal raw materials and the expected thickness of the thin film, the key parameters of the electron beam current, scanning frequency, and scanning range are carefully set, and the evaporation process is started. During the evaporation process, the highly sensitive remaining amount monitoring sensor of the raw materials accurately monitors the change in the remaining amount of the metal raw materials in the upper crucible in real time. This sensor uses advanced induction technology to accurately measure the remaining amount based on the physical property changes caused by the consumption of the raw materials. When it is monitored that the remaining amount of the raw materials is close to the preset threshold, the feeding program is immediately started. The preset threshold is comprehensively determined by multiple factors such as the evaporation rate of the raw materials, the past usage frequency, and the thin film thickness requirements. Through in-depth analysis of a large amount of historical evaporation data, a raw material consumption model is constructed, and combined with the current evaporation parameters, a weighted algorithm is used to accurately calculate the threshold to ensure that the feeding timing is just right and avoid adverse effects on the thin film quality caused by premature or late replacement of the raw materials.

[0032] Once the feeding program is triggered, the electromagnetic coil current of the electromagnetic connection device is gradually reduced semi-steadily according to a specific curve to ensure that the connection force between the upper crucible and the lower crucible decreases evenly and slowly, avoiding sudden changes in the connection force that may cause equipment vibration or crucible displacement deviation. At the same time, the telescopic robotic arm starts to slowly descend at a preset speed, and its descent speed is calculated by the formula Precisely calculated, where m is the mass of the upper crucible, and v is the instantaneous descending speed of the upper crucible when released by the robotic arm, which is accurately fitted from the rotational speed and transmission ratio of the robotic arm motor to ensure a smooth and safe descending process. The upper crucible is translated along the horizontal rail from the evaporation position to the transfer area above the lower crucible. When the robotic arm reaches the designated position in the transfer area, the upper crucible is precisely released to smoothly land on the carefully designed buffer lining on the top of the lower crucible. The elastic coefficient of the buffer lining is precisely calculated based on the weight and descending speed of the upper crucible, and the calculation formula is In the formula, Δh is the maximum allowable compression of the buffer pad, which is determined based on the elastic limit of the lining material and the equipment safety redundancy design to ensure that the impact force during the crucible landing process is effectively buffered and absorbed, protecting the crucible and equipment components from damage.

[0033] Subsequently, the upper crucible filled with new metal raw materials is smoothly moved along the horizontal rail from the raw material loading area outside the coating chamber to above the transfer area through the electric rail system. The raw material loading area is equipped with strict raw material pretreatment devices. Before the new raw materials are loaded into the upper crucible, the raw materials are comprehensively pretreated. The degree of raw material crushing is determined according to the particle size requirements of the electron beam evaporation process. Through the formula D crush = k c ×D evap Precisely calculated, where k c is the crushing coefficient to ensure that the particle size of the crushed raw materials is uniform and appropriate. The screening link adopts a multi-layer sieve structure, and the sieve pore size is precisely matched according to the crushing degree. During the stirring and mixing process, the stirring speed and time are precisely set according to the raw material characteristics and the requirements of mixing uniformity. Through the formula v mix = k m ×ρ mix ×V crucible and Precisely calculated, where k m is the stirring coefficient, ρ mix is the average density of the mixed raw materials, V crucible4 is the volume of the upper crucible, k t is the time coefficient, Q min 4 is the flow rate of the stirring device to ensure uniform mixing of the raw materials. The robotic arm descends along the vertical rail to the transfer area and precisely grabs the new upper crucible. Its crucible clamping device plays a key role. The inner sides of multiple adjustable jaws of the clamping device are equipped with sensitive pressure sensors, which are closely connected to the equipment control system in real time. When the robotic arm grabs the crucible, the pressure sensors quickly detect the pressure between the jaws and the crucible. The equipment control system precisely adjusts the clamping force of the jaws through the formula F adj4 = F4 init4 + k4 f4 ×(P4 s4 - P4 t4 4), where F4init4 is the initial clamping force setting value, k4 f4 is the pressure adjustment coefficient, P4 s4 is the actual detected pressure value of the pressure sensing sheet, P4 t4 is the target pressure value to ensure stable crucible clamping and no risk of damage. The robotic arm carries the new upper crucible and rises smoothly along the longitudinal slide rail, and then translates precisely along the transverse slide rail to the evaporation position. The motion trajectory planning of the robotic arm adopts an advanced artificial intelligence optimization algorithm, with the dual objective functions of the shortest total motion time from the robotic arm grasping the upper crucible to moving it to the evaporation position and the lowest energy consumption during the motion process. The objective function expression is J = w4 t4 ×T + w4 e4 ×E, where J is the comprehensive target value, w4 t4 is the time weight coefficient, w4 e4 is the energy weight coefficient, T is the total motion time, E is the total energy consumption. Through simulation calculation and real-time feedback adjustment, the motion path and speed curve of the robotic arm are optimized to ensure efficient, precise, and energy-saving motion, and to improve the overall operation efficiency of the equipment.

[0034] After the new crucible is accurately in place, increase the current of the electromagnetic coil of the electromagnetic connection device, and restore the connection force between the upper and lower crucibles to the initial stable state according to the preset current increase curve. This current increase curve is accurately designed based on the characteristics of electromagnetic materials and the mechanical requirements of the equipment to ensure stable connection and no risk of electromagnetic interference. According to the newly loaded raw material quantity, the target value of the film thickness, and the requirements of film uniformity, the parameters of the electron beam evaporation equipment are adjusted comprehensively and refined. The electron beam current adjustment is accurately calculated according to the formula I = k3×t×ρ×d, where k3 is the current coefficient, t is the target value of the film thickness, ρ is the raw material density, and d is the distance from the evaporation source to the substrate, to ensure the precise matching of the electron beam energy and the raw material evaporation rate. During the entire evaporation process, the vacuum pressure in the coating chamber is closely monitored in real time by a high-sensitivity pressure sensor. The pressure sensor uses high-precision piezoelectric sensing technology to real-time feedback the subtle changes in the vacuum pressure. When the pressure shows abnormal fluctuations, the vacuum compensation algorithm is immediately started for precise adjustment. The vacuum compensation algorithm formula is

[0035] where P4 comp4 is the vacuum compensation pressure value, P4 set4 is the preset vacuum pressure value, P4 act4 is the actual monitored vacuum pressure value, P4 prev4 is the actual monitored vacuum pressure value at the previous moment, k4 p4、 k4 i4、 k4 d4They are proportional, integral and differential coefficients respectively, which are determined by complex system identification and optimization algorithms. Δt is the time interval, which ensures that the vacuum environment is as stable as before and provides constant ideal conditions for thin film evaporation.

[0036] In summary, this embodiment demonstrates the practical application of a method for filling the crucible of an electron beam evaporation device without destroying the vacuum in the evaporation of a single metal film. By building a complete equipment system, accurately controlling the raw material balance monitoring, optimizing the crucible replacement process, finely adjusting the equipment parameters and maintaining a strict and stable vacuum environment, efficient and continuous thin film evaporation operations are achieved. This method effectively overcomes the disadvantages of traditional electron beam evaporation equipment that destroys the vacuum when filling the crucible, which is time-consuming and labor-intensive, and significantly improves production efficiency.

[0037] Embodiment 2

[0038] This embodiment focuses on achieving multi-layer composite thin film evaporation by using the crucible replenishment method of electron beam evaporation equipment. By carefully constructing adaptive equipment, reasonably configuring double-layer crucibles and precise control systems, when evaporating multi-layer thin films, the remaining raw material monitoring results of each layer are followed in sequence. Through the collaborative operation of electric slide rail systems, intelligent robotic arms, etc., efficient crucible replacement and parameter optimization adjustment are achieved. The vacuum stability and precision devices are maintained throughout the process to ensure that the thickness of each layer of the film is uniform, the structure is complete, and the adhesion is strong, which fully demonstrates the great advantages of this invention in improving the quality and efficiency in the field of multi-layer composite thin film evaporation.

[0039] Firstly, the electron beam evaporation equipment is carefully constructed in accordance with the requirements of the invention, and the upper and lower double-layer crucibles are precisely placed in the core area of ​​the coating chamber. The upper crucible is designed with partitions according to the characteristics of the raw materials of each layer of the multi-layer film to be evaporated and is equipped with an independent temperature control and raw material residue monitoring module to achieve precise control of each raw material. The lower crucible is used as a spare raw material storage warehouse to meet the needs of continuous evaporation of multi-layer films. At the same time, an intelligent raw material distribution system is provided to quickly and accurately replenish raw materials according to the needs of the upper crucible. The electric slide rail system is precisely installed in the coating chamber, and its transverse slide rail is vertically connected to the longitudinal slide rail. A high-performance robotic arm is configured on the longitudinal slide rail. The robotic arm integrates drive and positioning technology, and the crucible clamping device adopts an adaptive multi-joint structure and a flexible material buffer liner. Multiple joints work together to achieve multi-angle and stable clamping. The buffer liner calculates the elastic parameters through a complex mechanical model according to the weight and shape of different raw material crucibles to ensure that the clamping force is uniform, lossless and adaptable to various working conditions. In order to achieve precise coating control, high-resolution pressure sensors and multi-spectral raw material balance monitoring sensors are installed at key locations in the chamber. The pressure sensors are based on the principle of quantum tunneling, with a measurement accuracy of picometers, and can monitor tiny fluctuations in vacuum pressure in real time; the raw material balance monitoring sensors use multi-frequency electromagnetic induction and spectral analysis technology to accurately measure the balance of each raw material and provide key data for the evaporation process. At the same time, magnetic levitation drive technology is used in the electric slide rail system. Based on the overall mass, motion characteristics and electromagnetic principles of the crucible and the robotic arm, the formula where B is the driving magnetic field strength, m total is the total mass of the crucible and the robotic arm, g is the acceleration due to gravity, μ0 is the magnetic permeability of vacuum, N is the number of turns of the magnetic levitation coil, I is the coil current, and L is the length of the magnetic levitation track, ensuring smooth operation of the slide rail, no frictional loss, and a positioning accuracy of nanometer level, providing a solid guarantee for the precise movement of the crucible.

[0040] For the buffer lining on the top of the lower crucible, a micro-nano structure temperature sensor network is integrated inside to monitor the temperature field distribution of the lining in real time. According to the thermodynamic properties of the lining material and the thermal shock energy it withstands, the cooling power and start-up threshold of the cooling system are accurately calculated. The cooling system adopts high-efficiency microchannel liquid cooling technology, and the coolant flow rate and temperature are intelligently regulated according to the real-time temperature of the lining and the heat load of the evaporation process, ensuring the stable performance of the lining under multiple impacts and heat conduction during the lifting and lowering of the crucible, maintaining the internal thermal balance and structural stability of the equipment. A raw material pretreatment device is set in the raw material loading area. Before the new raw material is loaded into the upper crucible, the raw material pretreatment device pre-treats the raw material, including crushing, screening, and mixing. The degree of raw material crushing is determined according to the particle size of the raw material for the electron beam evaporation process: D crush = k c × D evap where D crush is the maximum particle diameter after raw material crushing, k c is the crushing coefficient, D evap is the optimal raw material particle diameter for electron beam evaporation. The screening uses a multi-layer sieve mesh structure, and the sieve mesh aperture is determined according to the degree of crushing. The stirring speed and time are determined according to the raw material characteristics and mixing uniformity: v mix = k m × ρ mix × V crucible , where v mix is the stirring speed, k m is the stirring coefficient, ρ mix is the average density of the mixed raw materials, V crucible is the volume of the upper crucible, t mix is the stirring time, k t is the time coefficient, Q mix is the flow rate of the stirring device

[0041] Start the electron beam evaporation equipment. According to the design and performance indicators of the multi-layer composite film structure, accurately set the initial parameters such as electron beam energy, scanning frequency, and scanning range for each raw material zone in the upper crucible, and start the multi-layer composite film evaporation process. During the entire evaporation process, the raw material residue monitoring sensor network continuously monitors the residue of each raw material. Relying on advanced signal processing and data analysis algorithms, a dynamic model of raw material consumption is constructed to predict the time point when the raw material is exhausted. The pressure sensor closely monitors the change in the vacuum pressure inside the coating chamber, and its data is transmitted to the core processor of the equipment control system in real time through a high-speed data acquisition system. The real-time feedback control algorithm is used to stabilize the vacuum degree to ensure that the evaporation environment is always in a ultra-high vacuum steady state. When the residue of a certain raw material zone in the upper crucible approaches the preset threshold, the equipment control system makes an intelligent decision to start the crucible replenishment program. According to the program logic, the control system precisely drives the electromagnetic connection device to gradually weaken the connection force between the crucible in the corresponding raw material zone and the lower crucible. The current decay curve is optimized based on the electromagnetic induction law and mechanical dynamics principles to ensure smooth and impact-free crucible separation. At the same time, the robotic arm moves precisely along the longitudinal and transverse sliding rails to the position above the crucible to be refilled according to the preset trajectory and speed curve (generated by the motion planning algorithm based on the equipment kinematic model and task priority). The clamping device adaptively adjusts the jaw posture and clamping force according to the geometric characteristics and mechanical parameters of the crucible, smoothly grabs the crucible and translates it along the sliding rail to the transfer area above the lower crucible, and then slowly lowers it onto the buffer liner. The elastic coefficient of the buffer liner is determined by where K is the elastic coefficient of the buffer pad, m is the mass of the upper crucible, v is the instantaneous descending speed of the robotic arm when releasing the upper crucible, and Δh is the maximum allowable compression of the buffer pad. The mass m of the upper crucible is obtained by pre-weighing the crucible and storing it in the equipment control system. The instantaneous descending speed v is fitted according to the rotational speed of the robotic arm motor and the transmission ratio to ensure smooth crucible landing, buffer the impact energy, and protect the equipment components.

[0042] After the upper crucible filled with new raw materials undergoes pre-treatment and quality inspection in the raw material filling area, it is transferred by a robotic arm along the horizontal slide rail from the filling area to above the transfer area according to precise trajectory and speed control. Then, it descends to grasp and lift and translate to the evaporation position. During the process, the movement trajectory of the robotic arm is continuously optimized. Its motion trajectory planning adopts a deep reinforcement learning algorithm. Taking the robotic arm movement time, energy consumption, crucible stability, and evaporation process continuity as the comprehensive optimization objectives, a complex reward function and state space model are constructed. Through simulation training to iteratively optimize the policy network, the robotic arm can achieve ultra-high efficiency and high-precision autonomous operation under complex working conditions, improving the overall operation efficiency of the equipment and the coating stability. At the junction of the alternating evaporation of each layer of thin film, the equipment executes the transition layer evaporation program. According to the material characteristics of adjacent film layers and the requirements of interface bonding, the proportion of the transition layer raw materials and the evaporation parameters are intelligently adjusted. The parameters are optimized through molecular dynamics simulation and experimental feedback to enhance the chemical bonding and physical adhesion between the film layers, eliminate interface defects, improve the overall structural integrity and performance synergy of the composite thin film, and achieve precise control of the multi-layer composite thin film from the microscopic atomic scale to the macroscopic performance.

[0043] In summary, this embodiment successfully verifies the excellent effectiveness of the method for replenishing the crucible of an electron beam evaporation device without breaking the vacuum in the evaporation of multi-layer composite thin films. By systematically constructing and synergistically optimizing the equipment structure, raw material processing system, crucible control mechanism, and parameter regulation strategy, high-efficiency, continuous, and precise evaporation of multi-layer composite thin films is achieved without breaking the vacuum environment. This method greatly improves the production efficiency of multi-layer composite thin films.

[0044] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claims involved.

Claims

1. A method for realizing crucible feeding of an electron beam evaporation device without breaking vacuum, characterized in that, The specific steps of this method are as follows: S100: Design the crucible of the electron beam evaporation equipment to have an upper and lower double-layer structure, where the upper crucible is used for evaporating raw materials, the lower crucible serves as a storage bin for spare raw materials, and an electric slide rail system that can precisely control displacement is installed in the coating cavity; S200: Set the threshold of the remaining raw material. When the remaining raw material monitoring sensor detects that the remaining raw material in the upper crucible is close to the threshold, start the robotic arm in the electric slide rail system to descend along the longitudinal slide rail, translate the upper crucible from the evaporation position to the transfer area above the lower crucible along the transverse slide rail, and the robotic arm releases the upper crucible to make it fall onto the buffer lining on the top of the lower crucible. The elastic coefficient of the buffer lining is calculated and determined according to the weight and descending speed of the upper crucible. The calculation process is as follows: Where K is the elastic coefficient of the buffer pad, m is the mass of the upper crucible, v is the instantaneous descending speed when the robotic arm releases the upper crucible, and Δh is the maximum allowable compression of the buffer pad. The mass m of the upper crucible is obtained by pre-weighing the crucible and storing it in the equipment control system. The instantaneous descending speed v is obtained by fitting the rotational speed of the robotic arm motor and the transmission ratio; S300: Move the upper crucible filled with new raw materials from the raw material loading area outside the coating cavity to above the transfer area along the horizontal slide rail through the electric slide rail system, and the robotic arm descends along the vertical slide rail to grab the new upper crucible; S400: The robotic arm carries the new upper crucible and ascends along the vertical slide rail and translates along the horizontal slide rail to the evaporation position; S500: Adjust the parameters of the electron beam evaporation equipment and continue the thin film evaporation operation. During the whole process, the vacuum pressure in the coating chamber is monitored in real time by a pressure sensor. When the pressure shows abnormal fluctuations, start the vacuum compensation algorithm for adjustment. The formula of the vacuum compensation algorithm is: where P comp is the vacuum compensation pressure value, P set is the preset vacuum pressure value, P act is the actually monitored vacuum pressure value, P prev is the actually monitored vacuum pressure value at the previous moment, k p , k i , k d are the proportional, integral, and differential coefficients respectively, Δt is the time interval, t0 is the starting time, and t is the current time.

2. A method for replenishing the crucible of an electron beam evaporation device without destroying the vacuum, as claimed in claim 1, wherein The electric slide rail system includes a horizontal slide rail and a vertical slide rail. The horizontal slide rail and the vertical slide rail are perpendicular to each other and connected. A robotic arm that can move up and down along the vertical slide rail is provided on the vertical slide rail, and a crucible clamping device is provided at the end of the robotic arm; At the same time, a pressure sensor and a raw material remaining amount monitoring sensor are arranged in the coating cavity. The pressure sensor is used to monitor the change of the vacuum pressure in the coating cavity, and the raw material remaining amount monitoring sensor is used to monitor the remaining amount of raw materials in the upper crucible.

3. A method for replenishing the crucible of an electron beam evaporation device without destroying the vacuum as claimed in claim 1, characterized in that The crucible clamping device of the robotic arm includes multiple adjustable jaws. A pressure sensing sheet is arranged on the inner side of the jaws, and the pressure sensing sheet is connected to the equipment control system. When the robotic arm grabs the crucible, the pressure sensing sheet detects the pressure between the jaws and the crucible, and the equipment control system adjusts the clamping force of the jaws according to the pressure value. The specific adjustment is as follows: F adj = F init + k f ×(P s - P t ), where F adj is the adjusted clamping force, F init is the initial clamping force setting value, k f is the pressure adjustment coefficient, P s is the actual value of the pressure sensing sheet, and P t is the target pressure value.

4. A method for replenishing the crucible of an electron beam evaporation device without destroying the vacuum as claimed in claim 1, characterized in that, The horizontal slide rail and the vertical slide rail in the electric slide rail system adopt magnetic levitation drive technology, and the driving magnetic field intensity is determined according to the overall weight of the crucible and the robotic arm: where B is the driving magnetic field intensity, m total is the total mass of the crucible and the robotic arm, g is the acceleration due to gravity, μ0 is the vacuum permeability, N is the number of turns of the magnetic levitation coil, I is the coil current, and L is the length of the magnetic levitation track.

5. A method for replenishing the crucible of an electron beam evaporation device without destroying the vacuum, as claimed in claim 1, characterized in that A temperature sensor is arranged inside the buffer lining at the top of the lower crucible. After the upper crucible falls onto the buffer lining, the temperature sensor detects the temperature change of the buffer lining. When the temperature is too high, the cooling system is started to cool down the buffer pad. The cooling power of the cooling system is determined according to the temperature rise amplitude of the buffer pad and the specific heat capacity of the buffer pad material: Where P cool is the cooling power, c is the specific heat capacity of the buffer pad material, m pad is the mass of the buffer pad, ΔT is the temperature rise value of the buffer pad, and Δt cool is the cooling time.

6. A method for replenishing the crucible of an electron beam evaporation device without destroying the vacuum, as described in claim 1, characterized in that The raw material loading area is provided with a raw material pretreatment device. Before the new raw material is loaded into the upper crucible, the raw material pretreatment device preprocesses the raw material, including crushing, screening, and mixing. The degree of raw material crushing is determined according to the particle size of the raw material for the electron beam evaporation process: D crush = k c × D evap , where D crush is the maximum particle diameter after raw material crushing, k c is the crushing coefficient, D evap is the optimal raw material particle diameter for electron beam evaporation. The screening uses a multi-layer screen structure, and the screen aperture is determined according to the crushing degree. The stirring speed and time are determined according to the raw material characteristics and mixing uniformity: v mix = k m × ρ mix × V crucible , where v mix is the stirring speed, k m is the stirring coefficient, ρ mix is the average density of the mixed raw materials, V crucible is the volume of the upper crucible, t mix is the stirring time, k t is the time coefficient, Q mix is the flow rate of the stirring device.

7. A method for replenishing the crucible of an electron beam evaporation device without destroying the vacuum as claimed in claim 1, characterized in that, The motion trajectory planning of the robotic arm adopts an artificial intelligence optimization algorithm, with the shortest total motion time of the robotic arm from grasping the upper crucible to moving it to the evaporation position and the lowest energy consumption during the motion process as the objective function. The expression of the objective function is J = w t ×T + w e ×E, where J is the comprehensive objective value, w t is the time weight coefficient, w e is the energy weight coefficient, T is the total motion time, E is the total energy consumption, and the motion control of the robotic arm is realized through the artificial intelligence optimization algorithm.

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