Partitioned multifunctional metal double-cavity vacuum coating process and system

Abstract

The invention discloses a partitioned multifunctional metal double-cavity vacuum coating process and system, and belongs to the technical field of material surface treatment. The process comprises the steps of base material pretreatment, double-cavity preparation, vacuum inspection, first cavity bottom layer deposition, vacuum transfer, second cavity functional layer deposition and cooling, the double cavities are provided with corresponding target materials respectively, and parallel operation and vacuum seamless transfer are supported; the system comprises double coating cavities, a vacuum transmission channel, a vacuum acquisition and control module, a coating deposition module, a workpiece bearing module and a process parameter regulation and control module, and each of the double cavities is provided with a multi-target mounting rack and carries a real-time monitoring unit and an intelligent control system. Integrated preparation of the composite film layer and synchronous production of multifunctional workpieces are achieved, operation gaps are eliminated, the compactness and adhesive force of the film layer are improved, parameter deviation and the reject ratio are reduced, and batch production requirements are met.

Description

Technical Field

[0001] This invention belongs to the field of material surface treatment technology, specifically relating to a partitioned multifunctional metal dual-cavity vacuum coating process and system. Background Technology

[0002] Vacuum coating refers to a technology that, in a vacuum environment, transforms coating materials (target materials) such as metals, alloys, and compounds into gaseous atoms, molecules, or ions through physical or chemical methods, and deposits them on the surface of a substrate (such as actuator gears, worm gears, electromagnet cores, housings, and other mechanical parts) to form a uniform, dense functional thin film. Its core characteristics are: the coating process is free from atmospheric interference (avoiding oxidation and pollution); the film has strong adhesion to the substrate; the thickness is controllable (from nanometer to micrometer level); and it can impart specific properties to the substrate such as wear resistance, corrosion resistance, friction reduction, conductivity, and heat insulation.

[0003] Traditional dual-cavity vacuum coating typically employs a "pretreatment chamber + single-function coating chamber" design. Each chamber can only load one type of target material, enabling the deposition of a single film layer (such as pure chromium or pure titanium). This fails to meet the composite requirements of "base layer + functional layer + sealing layer," and makes it difficult to simultaneously produce workpieces with different functions (such as decorative and anti-corrosion parts), resulting in poor adaptability. Changing the film type necessitates stopping the machine to replace the target material, taking 1-2 hours and reducing production flexibility. Traditional dual-cavity processes often involve "alternating operations," meaning the second coating chamber can only be pre-vacuumed while the first is coating, and the first is in a waiting state while the second is coating. This operational gap accounts for 30%-40% of the process, leading to low production efficiency per batch. Traditional processes rely on manual parameter calibration (such as gas flow rate and sputtering power), with parameter deviations easily reaching ±10%, resulting in differences in film thickness between the two chambers, fluctuations in zinc-aluminum alloy composition, and significant variations in gloss and hardness within the same batch of workpieces. The lack of real-time monitoring and closed-loop control means that when the film thickness and crystal structure deviate from the preset values, they cannot be adjusted in time, resulting in a failure rate of 10%-15%. Summary of the Invention

[0004] To address the aforementioned problems in the prior art, this invention provides a partitioned, multifunctional dual-cavity vacuum coating process for metals, comprising the following steps: S1, Substrate selection and pretreatment: Select the required substrate and use pretreatment methods such as physical cleaning, chemical impurity removal, and surface activation to make the substrate surface free of oil, oxidation, and slightly rough. S2, Preparation steps before coating of dual-cavity equipment: Install the bottom target material in the first coating cavity, install the functional layer target material in the second coating cavity, and debug the equipment after installation to ensure there are no abnormalities; S3, Vacuum inspection procedure: Close the dual-chamber door, perform helium mass spectrometry leak detection on the first coating chamber and the second coating chamber respectively, and perform vacuum pre-evacuation on the dual chamber after the inspection is completed; S4, First Coating Chamber Coating: Fix the pretreated substrate on the first coating chamber's rotating bracket, introduce argon gas into the first coating chamber, maintain the chamber pressure at 0.5-1 Pa, shield the substrate with a baffle, turn on the magnetron sputtering power supply, set the power to 300-400 W, pre-sputter the titanium target for 10-15 minutes to remove the oxide layer and contaminants on the target surface, close the baffle after pre-sputtering, adjust the argon gas flow rate in the first coating chamber to 20 sccm, maintain the chamber pressure at 0.3-0.5 Pa, apply a negative bias voltage of -100 V to -200 V to the substrate, start the sputtering power supply at 400-500 W, and begin depositing the titanium underlayer; monitor in real time with a film thickness gauge, when the thickness reaches 500 nm, reduce the power to 100 W and maintain it for 3 minutes to ensure the film layer is dense, then turn off the power to complete the first coating chamber underlayer coating; S5, Vacuum Transfer: The workpiece that has completed the bottom coating in the first coating chamber is transferred to the hanger in the second coating chamber under vacuum. S6, Second Coating Chamber Coating: Argon gas is introduced into the second coating chamber at a flow rate of 22-25 sccm, maintaining a chamber pressure of 0.5-0.7 Pa. The substrate is shielded by a baffle. The zinc-aluminum alloy target is pre-sputtered for 12-15 minutes at a power of 250-300 W, lower than the metal target power, to prevent over-melting of the target material and to thoroughly remove the oxide layer and contaminants on the target surface. The argon gas flow rate is adjusted to 18-22 sccm, the chamber pressure to 0.3-0.4 Pa, and the substrate negative bias voltage to -50V to -100V, lower than the metal target, to avoid excessive internal stress in the film layer. The sputtering power is 350-450 W, and the substrate temperature is 100-120℃. The baffle is closed, the power is turned on to start deposition, and the film thickness gauge provides real-time feedback data. When the thickness reaches 1500 nm, the power is reduced to 150 W and maintained for 5 minutes before the power is turned off to complete the zinc-aluminum alloy layer deposition. While the functional layer is deposited in the second coating chamber, the first coating chamber is depressurized, the workpiece with the bottom layer already deposited is removed, and a new batch of substrates is reloaded to begin coating, achieving seamless connection between the two chambers.

[0005] Furthermore, a cooling step is included after the coating process is complete: After the bottom layer of the first coating chamber is deposited, it is cooled to below 60°C under vacuum. After the functional layer in the second coating chamber is deposited, the process gas is shut off, and a vacuum state is maintained at a pressure of 5 × 10⁻⁻⁻⁻⁶. 4The chamber cooling system employs a combination of water cooling and slow cooling to reduce the substrate temperature from 120℃ to 80℃ at a rate of 3℃ / minute. It then cools from 80℃ to room temperature at a rate of 5℃ / minute over 18 minutes. Simultaneously, high-purity nitrogen is introduced and maintained at a slight positive pressure during cooling to create an inert protective atmosphere and prevent oxidation of the zinc-aluminum alloy layer. A gradient cooling system is used, with a preset cooling curve based on the film type, reducing the cracking rate of the zinc-aluminum alloy film, preventing oxidation and discoloration, shortening cooling time, and improving production efficiency.

[0006] Furthermore, the physical cleaning in step S1 includes polishing the surface of the substrate using sandpaper of different grits; the chemical cleaning includes immersing the substrate in an acetone solution bath and cleaning it under ultrasonic waves at a frequency of 40kHz and a power of 500W for 15-20 minutes, followed by transferring it to an ethanol solution bath and ultrasonic cleaning for 10-15 minutes; high-pressure spraying the substrate surface with deionized water for 3-5 minutes to rinse away residual reagents and microparticles; then immersing it in a deionized water ultrasonic bath for 8-12 minutes; finally, placing the substrate in a vacuum drying oven to dry. The activation process includes placing the dried substrate into a pretreatment chamber, evacuating it to 1×10⁻²Pa, introducing argon gas, turning on the plasma generator, applying a negative bias voltage of -500V to -800V, and bombarding the substrate surface with argon ions for 3-5 minutes to remove the surface oxide film and increase the surface active sites.

[0007] This invention also discloses a partitioned multifunctional metal dual-cavity vacuum coating system, comprising: The first coating chamber is responsible for the deposition of the substrate layer; The second coating chamber enables precise deposition of functional films. The vacuum transfer channel connects the first coating chamber and the second coating chamber, enabling the workpiece to be transferred in a vacuum environment. The vacuum acquisition and control module provides different levels of vacuum environment for the dual cavities; The film deposition module includes a target assembly, a sputtering power supply and ionization unit, and a gas distribution unit; The workpiece bearing module includes a rotating bracket connected to a negative bias power supply. Different negative bias voltages are applied to the dual cavities to enhance the ion bombardment effect and improve the film-substrate adhesion. The process parameter control module includes a temperature control system, a film thickness and composition monitoring unit, and an intelligent control system.

[0008] Furthermore, both the first and second coating cavities are equipped with multi-target mounting brackets, and the target material can be quickly switched by rotating the multi-target mounting brackets.

[0009] Furthermore, the vacuum transmission channel incorporates a magnetically levitated transmission robotic arm and a vacuum isolation valve.

[0010] Furthermore, the vacuum acquisition and control module includes a vacuum acquisition unit and a vacuum control unit; The vacuum acquisition unit includes a mechanical pump disposed in the first coating chamber and the second coating chamber, and a diffusion pump disposed in the second coating chamber; The vacuum control unit includes a thermocouple vacuum gauge and an ionization vacuum gauge located in the first coating chamber, and a high-precision ionization vacuum gauge located in the second coating chamber, which provides real-time feedback of chamber pressure data.

[0011] Furthermore, the target assembly includes a target holder and its cooling system, wherein the cooling system is a water-cooling channel disposed in the target holder; The gas distribution unit includes a multi-channel mass flow controller and a gas mixer to achieve precise proportioning of process gases and maintain stable chamber pressure.

[0012] Furthermore, the temperature control system includes a heating tube in the coating chamber and a water-cooling assembly in the chamber jacket; The film thickness and composition monitoring unit includes a quartz crystal film thickness gauge installed in a dual-cavity chamber to provide real-time feedback on the film thickness, and automatically triggers power adjustment when the preset value is reached; and an in-situ X-ray diffractometer (monitoring the crystal structure and refractive index) installed in the second coating chamber, which, together with a spectrometer, detects the crystal structure and refractive index respectively, and automatically adjusts the sputtering power and temperature when the crystal structure of the zinc-aluminum alloy film deviates from the preset value. Intelligent control system: The control platform is built based on PLC and touch screen. It has a preset database of process parameters for the "bottom layer - zinc-aluminum alloy layer" and supports one-click parameter recall. It collects key data such as chamber pressure, temperature and power in real time. As the core hub, it receives real-time data from modules such as vacuum control unit, film thickness and composition monitoring unit and sends instructions to each execution unit.

[0013] Compared with the prior art, the present invention has the following outstanding advantages: This invention exhibits significant technical advantages in a dual-cavity vacuum coating process. The second coating chamber utilizes precise temperature control at 80-120℃ and a 1×10⁻ 4With a high vacuum guarantee exceeding Pa, combined with high-purity argon deposition and nitrogen micro-positive pressure cooling protection, the oxidation and discoloration rate of the film layer is reduced to 0. A 12-15 minute pre-sputtering process removes the oxide layer from the target material, and a -50V to -100V substrate negative bias is applied to enhance the ion bombardment effect. Combined with a 5-minute low-power heat preservation process after deposition, the film density is increased by 40%, adhesion reaches 5B level, and salt spray resistance is ≥300 hours (500 hours after sealing). The system adopts a dual-cavity, multi-target integrated design. The first coating chamber can load various bottom-layer targets, while the second coating chamber is adapted to various functional layer targets. Target switching is rapid and supports parallel operation of both chambers. While the first chamber is depositing the bottom layer, the second chamber can simultaneously deposit zinc-aluminum alloy layers or produce different functional workpieces without requiring machine downtime for adjustment. A bidirectional vacuum transfer channel and a magnetic levitation robotic arm achieve "visual positioning + non-contact transfer," with a transfer time ≤30 seconds and uninterrupted vacuum environment, completely eliminating operational gaps. Meanwhile, the system builds a "bottom layer-functional layer" process parameter database. Inputting requirements will automatically match parameters with a deviation of ≤±5%. Combined with real-time feedback data from a quartz crystal film thickness gauge and an in-situ X-ray diffractometer, the system will automatically adjust when parameters deviate, ensuring consistent film performance and a high pass rate. It is perfectly suited for the needs of batch composite film production and simultaneous delivery of multiple orders. Attached Figure Description

[0014] Figure 1 The flowchart of a partitioned multifunctional metal dual-cavity vacuum coating process described in this invention. Detailed Implementation

[0015] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] like Figure 1 As shown, this invention discloses a partitioned multifunctional metal dual-cavity vacuum coating process. In this embodiment, the bottom target material is titanium and the functional layer target material is a zinc-aluminum alloy. The process includes the following steps: S1, Substrate selection and pretreatment: Select the required substrate and use pretreatment methods such as physical cleaning, chemical impurity removal, and surface activation to make the substrate surface free of oil, oxidation, and slightly rough. S2, Preparation steps before coating of dual-cavity equipment: Install the bottom target material in the first coating cavity, install the functional layer target material in the second coating cavity, and debug the equipment after installation to ensure there are no abnormalities; S3, Vacuum inspection procedure: Close the dual-chamber door, perform helium mass spectrometry leak detection on the first coating chamber and the second coating chamber respectively, and perform vacuum pre-evacuation on the dual chamber after the inspection is completed; S4, First Coating Chamber Coating: Fix the pretreated substrate on the first coating chamber's rotating bracket, introduce argon gas into the first coating chamber, maintain the chamber pressure at 0.5-1 Pa, shield the substrate with a baffle, turn on the magnetron sputtering power supply, set the power to 300-400 W, pre-sputter the titanium target for 10-15 minutes to remove the oxide layer and contaminants on the target surface, close the baffle after pre-sputtering, adjust the argon gas flow rate in the first coating chamber to 20 sccm, maintain the chamber pressure at 0.3-0.5 Pa, apply a negative bias voltage of -100 V to -200 V to the substrate, start the sputtering power supply at 400-500 W, and begin depositing the titanium underlayer; monitor in real time with a film thickness gauge, when the thickness reaches 500 nm, reduce the power to 100 W and maintain it for 3 minutes to ensure the film layer is dense, then turn off the power to complete the first coating chamber underlayer coating; S5, Vacuum Transfer: The workpiece that has completed the bottom coating in the first coating chamber is transferred to the hanger in the second coating chamber under vacuum. S6, Second Coating Chamber Coating: Argon gas is introduced into the second coating chamber at a flow rate of 22-25 sccm, maintaining a chamber pressure of 0.5-0.7 Pa. The substrate is shielded by a baffle. The zinc-aluminum alloy target is pre-sputtered for 12-15 minutes at a power of 250-300 W, lower than the metal target power, to prevent over-melting of the target material and to thoroughly remove the oxide layer and contaminants on the target surface. The argon gas flow rate is adjusted to 18-22 sccm, the chamber pressure to 0.3-0.4 Pa, and the substrate negative bias voltage to -50V to -100V, lower than the metal target, to avoid excessive internal stress in the film layer. The sputtering power is 350-450 W, and the substrate temperature is 100-120℃. The baffle is closed, the power is turned on to start deposition, and the film thickness gauge provides real-time feedback data. When the thickness reaches 1500 nm, the power is reduced to 150 W and maintained for 5 minutes before the power is turned off to complete the zinc-aluminum alloy layer deposition. While the functional layer is deposited in the second coating chamber, the first coating chamber is depressurized, the workpiece with the bottom layer already deposited is removed, and a new batch of substrates is reloaded to begin coating, achieving seamless connection between the two chambers.

[0017] In a preferred embodiment, a cooling step is further included after the coating is completed: After the bottom layer of the first coating chamber is deposited, it is cooled to below 60°C under vacuum. After the functional layer deposition in the second coating chamber is completed, the process gas is shut off and a vacuum state is maintained at 5×10⁻ 4 Pa, the chamber cooling system adopts a combination of water cooling and slow cooling to reduce the substrate temperature from 120℃ to 80℃ at a cooling rate of 3℃ / minute, and then cool it from 80℃ to room temperature at a cooling rate of 5℃ / minute for 18 minutes. At the same time, high-purity nitrogen is introduced and a slight positive pressure is maintained during the cooling process to form an inert protective atmosphere and prevent the zinc-aluminum alloy layer from oxidizing during cooling.

[0018] In a preferred embodiment, the physical cleaning in step S1 includes polishing the surface of the substrate using sandpaper of different grits; the chemical cleaning includes immersing the substrate in an acetone solution bath and cleaning it under ultrasonic waves at a frequency of 40kHz and a power of 500W for 15-20 minutes, followed by transferring it to an ethanol solution bath and ultrasonic cleaning for 10-15 minutes; high-pressure spraying the substrate surface with deionized water for 3-5 minutes to rinse away residual reagents and microparticles; then immersing it in a deionized water ultrasonic bath for 8-12 minutes; and finally placing the substrate in a vacuum drying oven to dry. The activation process includes placing the dried substrate into a pretreatment chamber, evacuating it to 1×10⁻²Pa, introducing argon gas, turning on the plasma generator, applying a negative bias voltage of -500V to -800V, and bombarding the substrate surface with argon ions for 3-5 minutes to remove the surface oxide film and increase the surface active sites.

[0019] The second coating chamber utilizes precise temperature control and vacuum assurance, maintaining a heating temperature between 80-120℃, and is equipped with a 1×10⁻ 4 In a high vacuum environment above Pa, high-purity argon gas is introduced during the deposition process, and nitrogen gas is introduced during the cooling stage for micro-positive pressure protection, reducing the oxidation and discoloration rate to 0. The oxide layer on the zinc-aluminum alloy target surface is removed by pre-sputtering for 12-15 minutes, and a negative bias voltage of -50V to -100V is applied to the substrate to enhance the ion bombardment effect. After deposition, a "low-power heat preservation for 5 minutes" process is adopted, which increases the film density by 40%, the salt spray resistance time is ≥300 hours (500 hours after sealing), and the adhesion reaches 5B level.

[0020] A partitioned, multifunctional dual-cavity vacuum coating system for metals, comprising: The first coating chamber is responsible for the deposition of the substrate layer; The second coating chamber enables precise deposition of functional films. The vacuum transfer channel connects the first coating chamber and the second coating chamber, enabling the workpiece to be transferred in a vacuum environment. The vacuum acquisition and control module provides different levels of vacuum environment for the dual cavities; The film deposition module includes a target assembly, a sputtering power supply and ionization unit, and a gas distribution unit; The workpiece bearing module includes a rotating bracket connected to a negative bias power supply. Different negative bias voltages are applied to the dual cavities to enhance the ion bombardment effect and improve the film-substrate adhesion. The process parameter control module includes a temperature control system, a film thickness and composition monitoring unit, and an intelligent control system.

[0021] Specifically, both the first and second coating cavities are equipped with multi-target mounting brackets, and the target material can be quickly switched by rotating the multi-target mounting brackets.

[0022] Specifically, the vacuum transmission channel incorporates a magnetically levitated transmission robotic arm and a vacuum isolation valve.

[0023] Specifically, the vacuum acquisition and control module includes a vacuum acquisition unit and a vacuum control unit; The vacuum acquisition unit includes a mechanical pump disposed in the first coating chamber and the second coating chamber, and a diffusion pump disposed in the second coating chamber; The vacuum control unit includes a thermocouple vacuum gauge and an ionization vacuum gauge located in the first coating chamber, and a high-precision ionization vacuum gauge located in the second coating chamber, which provides real-time feedback of chamber pressure data.

[0024] Specifically, the target assembly includes a target holder and its cooling system. The cooling system is a water-cooling channel located in the target holder to prevent the target material from melting and deforming due to its low melting point. The gas distribution unit includes a multi-channel mass flow controller and a gas mixer to achieve precise proportioning of process gases and maintain stable chamber pressure.

[0025] Specifically, the temperature control system includes a heating tube in the coating chamber and a water-cooling assembly in the chamber jacket; The film thickness and composition monitoring unit includes a quartz crystal film thickness gauge installed in a dual-cavity chamber to provide real-time feedback on the film thickness, and automatically triggers power adjustment when the preset value is reached; and an in-situ X-ray diffractometer (monitoring the crystal structure and refractive index) installed in the second coating chamber, which, together with a spectrometer, detects the crystal structure and refractive index respectively, and automatically adjusts the sputtering power and temperature when the crystal structure of the zinc-aluminum alloy film deviates from the preset value. Intelligent control system: The control platform is built based on PLC and touch screen. It has a preset database of process parameters for the "bottom layer - zinc-aluminum alloy layer" and supports one-click parameter recall. It collects key data such as chamber pressure, temperature and power in real time. As the core hub, it receives real-time data from modules such as vacuum control unit, film thickness and composition monitoring unit and sends instructions to each execution unit.

[0026] This invention employs a dual-cavity, multi-target integrated design. The first coating cavity can load different base target materials, while the second coating cavity can load different functional layer targets. This allows for the combination and rapid switching of various targets, supporting parallel operation of both cavities. While the first coating cavity deposits the base layer, the second coating cavity simultaneously deposits a zinc-aluminum alloy layer, or produces different functional workpieces separately without downtime for adjustments. This adapts to the needs of batch composite film production and simultaneous delivery of multiple orders. A bidirectional vacuum transfer channel equipped with a magnetically levitated robotic arm is built, allowing the second coating cavity to simultaneously deposit the zinc-aluminum alloy functional layer while the first coating cavity deposits the base layer. Workpiece transfer utilizes "visual positioning + non-contact transfer," with a transfer time ≤30 seconds, maintaining an uninterrupted vacuum environment and eliminating operational gaps. A "base layer-functional layer" database is established, automatically matching parameters after inputting requirements, with a deviation of ≤±5%. Real-time feedback of film thickness and crystal structure data is obtained using an in-situ X-ray diffractometer with a quartz crystal film thickness gauge. When parameters deviate, automatic adjustments are made (e.g., increasing sputtering power when the film thickness is too thin), resulting in a high rate of consistent film performance.

[0027] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements can be made without departing from the principle of the present invention, and these improvements should also be considered within the scope of protection of the present invention.

Claims

1. A partitioned, multifunctional dual-cavity vacuum coating process for metals, characterized in that, Includes the following steps: S1, Substrate selection and pretreatment: Select the required substrate and use pretreatment methods such as physical cleaning, chemical impurity removal, and surface activation to make the substrate surface free of oil, oxidation, and slightly rough. S2, Preparation steps before coating of dual-cavity equipment: Install the bottom target material in the first coating cavity, install the functional layer target material in the second coating cavity, and debug the equipment after installation to ensure there are no abnormalities; S3, Vacuum inspection procedure: Close the dual-chamber door, perform helium mass spectrometry leak detection on the first coating chamber and the second coating chamber respectively, and perform vacuum pre-evacuation on the dual chamber after the inspection is completed; S4, First Coating Chamber Coating: Fix the pretreated substrate on the first coating chamber's rotating bracket, introduce argon gas into the first coating chamber, maintain the chamber pressure at 0.5-1 Pa, shield the substrate with a baffle, turn on the magnetron sputtering power supply, set the power to 300-400 W, pre-sputter the titanium target for 10-15 minutes to remove the oxide layer and contaminants on the target surface, close the baffle after pre-sputtering, adjust the argon gas flow rate in the first coating chamber to 20 sccm, maintain the chamber pressure at 0.3-0.5 Pa, apply a negative bias voltage of -100 V to -200 V to the substrate, start the sputtering power supply at 400-500 W, and begin depositing the titanium underlayer; monitor in real time with a film thickness gauge, when the thickness reaches 500 nm, reduce the power to 100 W and maintain it for 3 minutes to ensure the film layer is dense, then turn off the power to complete the first coating chamber underlayer coating; S5, Vacuum Transfer: The workpiece that has completed the bottom coating in the first coating chamber is transferred to the hanger in the second coating chamber under vacuum. S6, Second Coating Chamber Coating: Argon gas is introduced into the second coating chamber at a flow rate of 22-25 sccm, maintaining a chamber pressure of 0.5-0.7 Pa. The substrate is shielded by a baffle. The zinc-aluminum alloy target is pre-sputtered for 12-15 minutes at a power of 250-300 W, lower than the metal target power, to prevent over-melting of the target material and to thoroughly remove the oxide layer and contaminants on the target surface. The argon gas flow rate is adjusted to 18-22 sccm, the chamber pressure to 0.3-0.4 Pa, and the substrate negative bias voltage to -50V to -100V, lower than the metal target, to avoid excessive internal stress in the film layer. The sputtering power is 350-450 W, and the substrate temperature is 100-120℃. The baffle is closed, the power is turned on to start deposition, and the film thickness gauge provides real-time feedback data. When the thickness reaches 1500 nm, the power is reduced to 150 W and maintained for 5 minutes before the power is turned off to complete the zinc-aluminum alloy layer deposition. While the functional layer is deposited in the second coating chamber, the first coating chamber is depressurized, the workpiece with the bottom layer already deposited is removed, and a new batch of substrates is reloaded to begin coating, achieving seamless connection between the two chambers.

2. The partitioned multifunctional dual-cavity vacuum coating process for metals according to claim 1, characterized in that, After the coating process is complete, a cooling step is also included: After the bottom layer of the first coating chamber is deposited, it is cooled to below 60°C under vacuum. After the functional layer deposition in the second coating chamber is completed, the process gas is shut off and a vacuum state is maintained at 5×10⁻ 4 Pa, the chamber cooling system adopts a combination of water cooling and slow cooling to reduce the substrate temperature from 120℃ to 80℃ at a cooling rate of 3℃ / minute, and then cool it from 80℃ to room temperature at a cooling rate of 5℃ / minute for 18 minutes. At the same time, high-purity nitrogen is introduced and a slight positive pressure is maintained during the cooling process to form an inert protective atmosphere and prevent the zinc-aluminum alloy layer from oxidizing during cooling.

3. The partitioned multifunctional dual-cavity vacuum coating process for metals according to claim 1, characterized in that, The physical cleaning described in step S1 includes polishing the surface of the substrate using sandpaper of different grits; the chemical cleaning includes immersing the substrate in an acetone solution bath and cleaning it under ultrasonic waves at a frequency of 40kHz and a power of 500W for 15-20 minutes, followed by transferring it to an ethanol solution bath and ultrasonic cleaning for 10-15 minutes; high-pressure spraying the substrate surface with deionized water for 3-5 minutes to rinse away residual reagents and microparticles; then immersing it in a deionized water ultrasonic bath for 8-12 minutes; finally, placing the substrate in a vacuum drying oven to dry. The activation process includes placing the dried substrate into a pretreatment chamber, evacuating it to 1×10⁻²Pa, introducing argon gas, turning on the plasma generator, applying a negative bias voltage of -500V to -800V, and bombarding the substrate surface with argon ions for 3-5 minutes to remove the surface oxide film and increase the surface active sites.

4. A partitioned multifunctional dual-cavity vacuum coating system for metals, used to implement the partitioned multifunctional dual-cavity vacuum coating process described in any one of claims 1-3, characterized in that, include: The first coating chamber is responsible for the deposition of the substrate layer; The second coating chamber enables precise deposition of functional films. The vacuum transfer channel connects the first coating chamber and the second coating chamber, enabling the workpiece to be transferred in a vacuum environment. The vacuum acquisition and control module provides different levels of vacuum environment for the dual cavities; The film deposition module includes a target assembly, a sputtering power supply and ionization unit, and a gas distribution unit; The workpiece bearing module includes a rotating bracket connected to a negative bias power supply. Different negative bias voltages are applied to the dual cavities to enhance the ion bombardment effect and improve the film-substrate adhesion. The process parameter control module includes a temperature control system, a film thickness and composition monitoring unit, and an intelligent control system.

5. The partitioned multifunctional dual-cavity metal vacuum coating system according to claim 4, characterized in that, Both the first and second coating cavities are equipped with multi-target mounting brackets, and the target material can be quickly switched by rotating the multi-target mounting brackets.

6. The partitioned multifunctional dual-cavity metal vacuum coating system according to claim 4, characterized in that, The vacuum transmission channel incorporates a magnetically levitated transmission robotic arm and a vacuum isolation valve.

7. A partitioned multifunctional dual-cavity metal vacuum coating system according to claim 4, characterized in that, The vacuum acquisition and control module includes a vacuum acquisition unit and a vacuum control unit; The vacuum acquisition unit includes a mechanical pump disposed in the first coating chamber and the second coating chamber, and a diffusion pump disposed in the second coating chamber; The vacuum control unit includes a thermocouple vacuum gauge and an ionization vacuum gauge located in the first coating chamber, and a high-precision ionization vacuum gauge located in the second coating chamber, which provides real-time feedback of chamber pressure data.

8. A partitioned multifunctional dual-cavity vacuum coating system for metals according to claim 4, characterized in that, The target assembly includes a target holder and its cooling system, wherein the cooling system is a water-cooling channel located in the target holder; The gas distribution unit includes a multi-channel mass flow controller and a gas mixer to achieve precise proportioning of process gases and maintain stable chamber pressure.

9. A partitioned multifunctional dual-cavity metal vacuum coating system according to claim 4, characterized in that, The temperature control system includes a heating tube in the coating chamber and a water-cooling assembly in the chamber jacket. The film thickness and composition monitoring unit includes a quartz crystal film thickness gauge installed in a dual-cavity chamber to provide real-time feedback on the film thickness, and automatically triggers power adjustment when the preset value is reached; and an in-situ X-ray diffractometer (monitoring the crystal structure and refractive index) installed in the second coating chamber, which, together with a spectrometer, detects the crystal structure and refractive index respectively, and automatically adjusts the sputtering power and temperature when the crystal structure of the zinc-aluminum alloy film deviates from the preset value. Intelligent control system: The control platform is built based on PLC and touch screen, with a preset database of process parameters for the "bottom layer - zinc-aluminum alloy layer", and supports one-click parameter recall; It collects key data such as chamber pressure, temperature, and power in real time, and serves as the core hub to receive real-time data from modules such as the vacuum control unit, film thickness and composition monitoring unit, and send instructions to each execution unit.

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