Pulse laser induced high-ionization magnetron sputtering and ion energy control method and device

Abstract

The invention provides a pulse laser induced high-ionization magnetron sputtering and ion energy control method and device, and relates to the technical field of magnetron sputtering coating. The control method comprises the following steps: S1, mounting a target material and a substrate in place in a vacuum chamber, sealing the vacuum chamber, and vacuumizing the vacuum chamber to a vacuum state; s2, argon is introduced into the vacuum chamber, and the working air pressure is controlled to be stabilized at a preset value; turning on an anode power supply to supply power to the target material, and grounding the chamber wall of the vacuum chamber; s3, the surface of the target material is scanned according to a preset path after the pulse laser is controlled to be focused, secondary electron emission is excited, and the ionization rate of sputtering metal atoms in the plasma is increased; plasma density data are synchronously monitored in real time, and the laser power density is dynamically adjusted based on a preset plasma density threshold value; and S4, establishing an electric field, accelerating the positively charged target material ions to move towards the substrate under the action of the electric field, and depositing on the surface of the substrate to form a coating film.

Description

Technical Field

[0001] This invention relates to the field of magnetron sputtering coating technology, and more specifically, to a method and apparatus for pulsed laser-induced high-ionization magnetron sputtering and ion energy control. Background Technology

[0002] In traditional magnetron sputtering, most sputtered target particles fly towards the substrate as neutral atoms or atomic clusters, with an ionization rate generally below 10%, often remaining between 5% and 8%. This results in uncontrollable particle energy and motion direction during film deposition, affecting film density, film-substrate bonding, and uniformity. High-power pulsed magnetron sputtering (HiPIMS) improves film quality by altering the plasma discharge range using a pulsed magnetron sputtering power supply, increasing sputtered ion energy and achieving a higher ionization rate. However, HiPIMS suffers from a narrow discharge window, complex power supply system control, and equipment costs 3-5 times higher than DC systems.

[0003] Therefore, there is an urgent need for a control method and device that can maintain a high ionization rate and good membrane quality, while also having a wide range of process adaptability, lower equipment costs, and higher operational stability, so as to promote the development of membrane fabrication technology towards a more efficient and economical direction. Summary of the Invention

[0004] The purpose of this invention is to provide a method and apparatus for pulsed laser-induced high-ionization magnetron sputtering and ion energy control, which addresses the shortcomings of existing technologies and solves the problems mentioned in the background.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A method for pulsed laser-induced high-ionization magnetron sputtering and ion energy control includes the following steps: S1. Install the target and substrate in the vacuum chamber, seal the vacuum chamber, and evacuate the vacuum chamber to a vacuum state; S2. Introduce argon gas into the vacuum chamber and control the working pressure to stabilize at the preset value; turn on the positive power supply to supply power to the target material, and ground the chamber wall of the vacuum chamber; S3. After focusing the pulsed laser, it scans the target surface along a preset path to excite secondary electron emission and improve the ionization rate of sputtered metal atoms in the plasma; simultaneously, it monitors the plasma density data in real time and dynamically adjusts the laser power density based on the relationship between the preset plasma density threshold and the real-time plasma density data. S4. Turn on the negative electrode power supply of the substrate to establish an electric field between the substrate and the target material at a positive potential. The positively charged target material ions are accelerated towards the substrate under the action of the electric field and deposited on the substrate surface to form a coating.

[0006] Further, in step S1, the background vacuum level inside the vacuum chamber is evacuated to 5 × 10⁻⁶. -3 Pa level.

[0007] Furthermore, in step S2, the preset value of the working air pressure is 0.5 Pa.

[0008] Furthermore, in step S3, the pulsed laser is controlled to scan the target surface in a concentric circle or a linear path.

[0009] Furthermore, in step S3, the scanning speed of the pulsed laser is 5-50 mm / s, and the scanning gap is 0.5-2 mm.

[0010] Furthermore, in step S3, the laser pulse width is 100 ns, the repetition frequency is 20 kHz, and the peak power density is 1-10 kW / cm².

[0011] Furthermore, in step S4, the positively charged target ions gain kinetic energy of 10-100 eV in the electric field.

[0012] A device for pulsed laser-induced high-ionization magnetron sputtering and ion energy is applicable to the above-mentioned control method, including existing magnetron sputtering coating equipment. The magnetron sputtering coating equipment includes a vacuum chamber and a positive power supply. The vacuum chamber is provided with a base for placing the target and a base for placing the substrate. The positive terminal of the positive power supply is used to supply power to the target, and the negative terminal of the positive power supply is grounded. An optical glass window is provided on the wall of the vacuum chamber. It also includes a laser-assisted system and a detection device. The detection device is electrically insulated and sealed on the wall of the vacuum chamber and is electrically connected to the laser-assisted system. The laser-assisted system is used to emit pulsed lasers to scan the target material through an optical glass window along a preset path. The detection device is used to monitor plasma density data in real time and transmit it to the laser-assisted system.

[0013] Furthermore, the laser-assisted system includes a control unit, a laser emitting unit, and a focusing unit, with the control unit and the laser emitting unit being electrically connected.

[0014] Preferably, it also includes a negative power supply, the negative terminal of which is electrically connected to the substrate, and the positive terminal of which is grounded, so that an electric field is formed between the substrate and the target material.

[0015] The present invention has at least the following advantages or beneficial effects: This invention provides a pulsed laser-induced high-ionization magnetron sputtering and ion energy control method. By scanning the target surface with a pulsed laser beam, secondary electron emission can be effectively excited, increasing the initial ionization rate to 25%-35%. Finally, an electric field is applied between the substrate and the vacuum chamber wall, forming an ion acceleration channel that allows the deposited ions to obtain controllable energy of 10-100 eV. The introduction of the electric field allows for precise control of the trajectory and energy distribution of the deposited ions, significantly improving ion energy controllability. Deposited ions can impact the substrate surface with optimal energy, effectively improving film density and adhesion, and enhancing film quality. By comparing the plasma density with a preset plasma density threshold in real time, the laser power density is dynamically adjusted to achieve closed-loop dynamic optimization, stabilizing the ionization rate at 30%-40%, far exceeding the 10% of traditional techniques.

[0016] This invention provides a device for pulsed laser-induced high-ionization magnetron sputtering and ion energy generation. By incorporating a laser-assisted system, a detection device, and an optical glass window through which the laser beam passes, the laser beam is focused onto the dynamically scanning target, exciting secondary electron emission and thus increasing the initial ionization rate. The detection device can monitor plasma density data in real time and transmit it back to the laser-assisted system, enabling the system to automatically increase the laser power density. Furthermore, the device includes a negative power supply to power the substrate, creating an electric field between the substrate and the target. Positively charged target ions (deposited ions) gain kinetic energy in this electric field, and the device allows for precise control of the deposited ions, effectively improving film density and adhesion, and enhancing film quality. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A flowchart of a pulsed laser-induced high-ionization magnetron sputtering and ion energy control method provided by the present invention; Figure 2 A schematic diagram of the internal structure of a device for pulsed laser-induced high-ionization magnetron sputtering and ion energy provided by the present invention; Figure 3 The concentric circle scanning path provided by this invention; Figure 4 The linear scanning path provided by this invention.

[0019] Icons: 1. High-purity argon gas storage device; 2. Laser emitting unit; 3. Laser field lens; 4. Control unit; 5. Vacuum chamber; 6. Sealed connection port; 7. Optical glass window; 8. Pulsed laser; 9. Coating; 10. Substrate; 11. Substrate negative electrode power supply; 12. Negative electrode sealed insulating sleeve; 13. Target material; 16. Electric field line; 17. Target material ions; 18. Argon plasma; 19. Positive electrode sealed insulating sleeve; 20. Positive electrode power supply; 21. Detection device; 22. Probe sealed sleeve; 23. Grounding wire; 24. Vacuum pumping device; 25. Valve. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0021] Please refer to Figure 1 As shown, this invention provides a method for pulsed laser-induced high-ionization magnetron sputtering and ion energy control, comprising the following steps: S1. Install the target material and substrate in the vacuum chamber, seal the vacuum chamber, and evacuate the background vacuum level inside the vacuum chamber to 5×10⁻⁶. -3 The Pa level provides a clean, high-vacuum environment for the subsequent deposition process.

[0022] S2. High-purity argon gas is introduced into the vacuum chamber, and the working pressure is stabilized at 0.5 Pa by precisely controlling the gas flow; the positive power supply is turned on to supply power to the target material, while ensuring that the vacuum chamber is properly grounded through the grounding wire. Under these conditions, the argon gas is ionized, forming a basic argon plasma in the chamber.

[0023] S3. Control the laser emitting unit to emit pulsed laser light. After focusing, the pulsed laser scans the target surface along a preset path, which includes, but is not limited to, concentric circles or linear paths. The pulsed laser scanning of the target surface effectively excites secondary electron emission, increasing the ionization rate of sputtered metal atoms in the plasma. Simultaneously, plasma density data is monitored in real time. Based on the relationship between a preset plasma density threshold and the real-time plasma density data, the laser power and scanning parameters are dynamically adjusted to stably improve the ionization rate.

[0024] Specifically, the scanning speed of the pulsed laser is 5-50 mm / s, preferably 10 mm / s, and the scanning gap is 0.5-2 mm, preferably 0.5 mm. The laser pulse width is 100 ns, the repetition frequency is 20 kHz, and the peak power density is 1-10 kW / cm². 2 .

[0025] S4. Turn on the negative electrode power supply of the substrate to establish an electric field between the substrate and the target material, which is at a positive potential. This electric field is formed by the potential difference between the target material and the substrate. Under the action of the electric field, the positively charged target material ions are accelerated towards the substrate, thereby obtaining controllable energy of 10-100 eV. This allows for precise control of the ion trajectory and energy, thereby optimizing the microstructure and performance of the final coating.

[0026] Please refer to Figures 2 to 4 As shown, this application also provides a device for pulsed laser-induced high-ionization magnetron sputtering and ion energy, applicable to the above-mentioned control method. It includes existing magnetron sputtering coating equipment, which includes a vacuum chamber 5 grounded via a grounding wire 23. A vacuum pump or molecular pump, or other vacuum extraction device 24, is installed on the vacuum chamber 5, and a valve 25 controls the disconnection between the vacuum chamber 5 and the vacuum extraction device 24. The vacuum chamber 5 also has a sealed connection port 6 for connecting an external high-purity argon gas storage device 1, through which the high-purity argon gas storage device 1 supplies high-purity argon gas into the vacuum chamber 5. The vacuum chamber 5 is equipped with a threaded base with a water-cooling channel for placing the target material and a base for placing the substrate 10. A positive power supply 20 is located outside the vacuum chamber 5. The positive terminal of the positive power supply 20 is electrically connected to the base via a wire passing through the side wall of the vacuum chamber 5. A positive terminal sealing insulating sleeve 19 is fitted onto the wire and is sealed to the side wall of the vacuum chamber 5 through the sealing insulating sleeve 19. The negative terminal of the positive power supply 20 is grounded. When the positive power supply 20 is turned on, it supplies power to the target material 13, ionizing argon gas and forming a basic argon plasma 18 within the chamber.

[0027] In addition, an optical glass window 7 and a detection device 21 are sealed on the wall of the vacuum chamber 5; a laser-assisted system is installed outside the vacuum chamber 5. The detection device 21 is electrically connected to the laser-assisted system. The optical glass window 7 is made of high borosilicate glass, which has good light transmittance, minimal energy loss when the laser passes through the window, and high thermal stability / mechanical strength, maintaining good performance under high temperature and pressure. The laser-assisted system is used to emit pulsed laser 8 to scan the target material through the optical glass window 7 along a preset path. The detection device 21 is used to monitor plasma density data in real time and transmit it to the laser-assisted system, enabling the laser-assisted system to automatically adjust the power density of the pulsed laser 8.

[0028] Specifically, the laser-assisted system includes a laser emitting unit 2, a focusing unit 3, and a control unit 4, with the control unit 4 electrically connected to the laser emitting unit 2. The laser emitting unit 2 is an existing laser generator, whose emitted pulsed laser 5 only needs to meet the requirements of a wavelength of 1064 nm and a single pulse energy of 200 mJ to 15 J. The focusing unit 3 is a laser field lens, and the control unit 4 is a host computer. The control unit 4 has built-in EzCad laser control software for parameter setting. Parameters include the scanning speed, scanning gap, pulse width, repetition frequency, peak power density, scanning path, and plasma density threshold of the pulsed laser 8. The scanning speed is 5-50 mm / s (preferably 10 mm / s), the scanning gap is 0.5-2 mm (preferably 0.5 mm), the laser pulse width is 100 ns, the repetition frequency is 20 kHz, and the peak power density is 1-10 kW / cm². 2 (Preferred power: 3 kW / cm) 2 The scanning path includes, but is not limited to, concentric circles or linear paths.

[0029] The detection device 21 is fitted with a probe sealing sleeve 22, which is sealed to the wall of the vacuum chamber 5. The detection device 21 is an existing Langmuir probe, which is electrically connected to the control unit 4.

[0030] After setting the relevant parameters of the pulsed laser 8 using the EzCad laser control software, the laser emitting unit 2 is turned on. The pulsed laser 8 emitted by the laser emitting unit 2 is focused by the focusing unit 3 and penetrates the optical glass window into the vacuum chamber 5, ultimately irradiating the target surface. The control unit 4 controls the pulsed laser 8 to scan the target surface with preset parameters. The detection device 21 monitors the plasma density data in real time and transmits the data back to the control unit 4. The control unit 4 compares the transmitted data with a preset plasma density threshold. When the plasma density is less than the preset plasma density threshold, the control unit 4 can control the laser emitting unit 2 to increase the power density of the pulsed laser 8 (e.g., by 0.5 kW / cm²), thereby realizing a closed-loop feedback mechanism to keep the plasma density in the vacuum chamber 5 stable, thus significantly improving the ionization rate of sputtered metal atoms in the plasma.

[0031] Preferably, the device further includes a negative power supply 11. The negative terminal of the negative power supply 11 is electrically connected to the substrate 10 via a wire passing through the wall of the vacuum chamber 5. A negative terminal sealing and insulating sleeve 12 is fitted on the wire to ensure that the wire is sealed and insulated from the wall of the vacuum chamber 5. The positive terminal of the negative power supply 11 is grounded, thereby forming an electric field between the substrate 10 and the target material 13. To more vividly demonstrate the electric field... Figure 2The electric field line 16 is shown. Under the action of this electric field, the positively charged target ions 17 are accelerated to move towards the substrate 10, thereby obtaining controllable energy of 10-100 eV, realizing precise control of the ion trajectory and energy, and thus optimizing the microstructure and performance of the final coating 9.

[0032] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. 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 method for pulsed laser-induced high-ionization magnetron sputtering and ion energy control, characterized in that, Includes the following steps: S1. Install the target and substrate in the vacuum chamber, seal the vacuum chamber, and evacuate the vacuum chamber to a vacuum state; S2. Introduce argon gas into the vacuum chamber and control the working pressure to stabilize at the preset value; turn on the positive power supply to supply power to the target material, and ground the chamber wall of the vacuum chamber; S3. After focusing the pulsed laser, it scans the target surface along a preset path to excite secondary electron emission and improve the ionization rate of sputtered metal atoms in the plasma; simultaneously, it monitors the plasma density data in real time and dynamically adjusts the laser power density based on the relationship between the preset plasma density threshold and the real-time plasma density data. S4. Turn on the negative electrode power supply of the substrate to establish an electric field between the substrate and the target. The positively charged target ions are accelerated towards the substrate under the action of the electric field and deposited on the substrate surface to form a coating.

2. The method for pulsed laser-induced high-ionization magnetron sputtering and ion energy control according to claim 1, characterized in that, In step S1, the background vacuum level inside the vacuum chamber is evacuated to 5 × 10⁻⁶. -3 Pa level.

3. The method for pulsed laser-induced high-ionization magnetron sputtering and ion energy control according to claim 1, characterized in that, In step S2, the preset value of the working air pressure is 0.5 Pa.

4. The method for pulsed laser-induced high-ionization magnetron sputtering and ion energy control according to claim 1, characterized in that, In step S3, the pulsed laser is controlled to scan the target surface in concentric circles or a linear path.

5. The method for pulsed laser-induced high-ionization magnetron sputtering and ion energy control according to claim 1, characterized in that, In step S3, the scanning speed of the pulsed laser is 5-50 mm / s, and the scanning gap is 0.5-2 mm.

6. The method for pulsed laser-induced high-ionization magnetron sputtering and ion energy control according to claim 1, characterized in that, In step S3, the laser pulse width is 100 ns, the repetition frequency is 20 kHz, and the peak power density is 1-10 kW / cm².

7. The method for pulsed laser-induced high-ionization magnetron sputtering and ion energy control according to claim 1, characterized in that, In step S4, the positively charged target ions gain kinetic energy of 10-100 eV in the electric field.

8. A device for pulsed laser-induced high-ionization magnetron sputtering and ion energy, applicable to the control method described in any one of claims 1-7, characterized in that, The invention includes existing magnetron sputtering coating equipment, which comprises a vacuum chamber and a positive power supply. The vacuum chamber is provided with a base for placing a target and a base for placing a substrate. The positive terminal of the positive power supply is used to supply power to the target, and the negative terminal of the positive power supply is grounded. An optical glass window is provided on the wall of the vacuum chamber. It also includes a laser-assisted system and a detection device. The detection device is electrically insulated and sealed on the wall of the vacuum chamber and is electrically connected to the laser-assisted system. The laser-assisted system is used to emit pulsed laser light through the optical glass window to scan the target material along a preset path. The detection device is used to monitor plasma density data in real time and transmit it to the laser-assisted system.

9. The apparatus for pulsed laser-induced high-ionization magnetron sputtering and ion energy according to claim 8, characterized in that, The laser-assisted system includes a control unit, a laser emitting unit, and a focusing unit, wherein the control unit and the laser emitting unit are electrically connected.

10. The apparatus for pulsed laser-induced high-ionization magnetron sputtering and ion energy according to claim 8, characterized in that, It also includes a negative power supply, the negative terminal of which is electrically connected to the substrate, and the positive terminal of which is grounded, forming an electric field between the substrate and the target material.

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