A magnetron target and sputtering method for preparing multi-element composite thin film

Abstract

The present invention belongs to the technical field related to magnetron sputtering thin film deposition, and discloses a magnetron target and a sputtering method for preparing a multi-element composite thin film, wherein the magnetron target comprises a multi-element splicing target, a cooling water system and a magnetron system, wherein the cooling water system is arranged between the multi-element splicing target and the magnetron system; the cooling water system comprises a cooling water channel and a magnetic shielding louver, wherein the magnetic shielding louver is arranged in the cooling water channel, and is used to selectively magnetically shield the target surface of the multi-element splicing target; the magnetic shielding louver corresponds to the position of the multi-element splicing target, and the magnetic shielding louver can rotate and retract relative to the cooling water channel; the magnetron target controls the magnetic field strength of each area of ​​the target surface of the multi-element splicing target by rotating and retracting the magnetic shielding louver, thereby adjusting the sputtering intensity of the corresponding elements in each area of ​​the multi-element splicing target. The present invention realizes the sputtering of multiple elements simultaneously or in turn by a single target platform, and solves the problem that a single magnetron target cannot prepare composite materials and multilayer films.

Description

Technical Field

[0001] The present invention belongs to the technical field related to magnetron sputtering thin film deposition, and more specifically, relates to a magnetron target and a sputtering method for preparing a multi-element composite thin film. Background Art

[0002] Magnetron sputtering is a metal and compound thin film deposition technology that can deposit large-area smooth coatings at relatively low temperatures, and the sputtering process has fewer restrictions on the target material. Therefore, it is widely used in integrated circuits, wear-resistant and anti-corrosion coatings, optical coatings, large-area coatings for architectural glass, photovoltaic solar cells and other fields. Magnetron sputtering occurs in a high vacuum environment, where the cathode target is bombarded by high-energy particles generated in the glow discharge plasma, producing a large number of target particles. Under the action of the magnetic field (B), the electrons move along a spiral trajectory, and their residence time in the plasma is prolonged, which increases the probability of collision between the electrons and the gas atoms, causing a large number of argon atoms to ionize to form argon ions (Ar + ). Under the action of the electric field (E), high-energy argon ions are accelerated to bombard the target material, sputtering out target particles, and finally the target metal is deposited on the surface of the substrate to form the desired coating.

[0003] With the increasing demand for functional coatings and layered structures, magnetron sputtering technology is developing in the direction of adapting to the preparation process of new materials. Functional coatings are thin film materials with properties such as high temperature resistance, corrosion resistance, oxidation resistance, and high hardness, and are usually composed of a variety of elements. Layered structure materials are a layer of nanometer-thick material, and then one or more layers of other thin layers of materials with different properties are plated on it to finally form a multi-layer film. The preparation of new film layers requires the co-sputtering and rotation sputtering processes of multiple elements. However, in traditional magnetron sputtering, a single target station starts and stops the sputtering of the target material by switching the target power supply. The preparation of high-performance composite materials and multi-layer films requires multiple target stations to control the sputtering of the target material separately. The process flow is complicated, and the number of target stations and target power supplies limits its industrial application. Therefore, how to design a magnetron target and sputtering method that can realize multi-element co-sputtering and wheel sputtering processes is a problem that technicians in this field urgently need to solve. Summary of the invention

[0004] In view of the above defects or improvement needs of the prior art, the present invention provides a magnetron target and sputtering method for preparing multi-element composite thin films, which can control the strength of the magnetic field in each area of ​​the target surface by adjusting the opening and closing degree of the magnetic shielding shutters, and with the assistance of rotating magnetic modules of different strengths to different positions, thereby affecting the sputtering intensity of the corresponding elements in each area of ​​the spliced ​​target, and realizing the connection adjustment of the film layer components and the relative content of elements. The present invention can realize the preparation of multi-element composite thin films such as gradient ratio alloy films and custom component multilayer films by single or multiple magnetron targets, with high flexibility, simple control process and wide application range.

[0005] To achieve the above-mentioned object, according to one aspect of the present invention, a magnetron target for preparing a multi-element composite thin film is provided, the magnetron target comprising a multi-element spliced ​​target, a cooling water system and a magnetron system, the cooling water system being arranged between the multi-element spliced ​​target and the magnetron system; the cooling water system comprising a cooling water channel and a magnetic shielding louver, the magnetic shielding louver being arranged in the cooling water channel, and being used for selectively magnetically shielding the target surface of the multi-element spliced ​​target;

[0006] The magnetic shielding louvers correspond to the positions of the multi-element spliced ​​target, and the magnetic shielding louvers can rotate and extend relative to the cooling water channel; the magnetron target controls the strength of the magnetic field in each area of ​​the target surface of the multi-element spliced ​​target through the rotation and extension of the magnetic shielding louvers, thereby adjusting the sputtering intensity of the corresponding elements in each area of ​​the multi-element spliced ​​target.

[0007] Furthermore, the central axis of the multi-element spliced ​​target, the central axis of the cooling water system and the central axis of the magnetron system coincide with each other.

[0008] Furthermore, the multi-element spliced ​​target is composed of a plurality of single element target materials spliced ​​into one piece, and is a circular target or a square target.

[0009] Furthermore, the cooling water channel is in a concave shape, the magnetic control system part is arranged in the cavity formed by the cooling water channel, the multi-element spliced ​​target is opposite to the middle part of the cooling water channel; and the magnetic shielding louver is located in the middle part of the cooling water channel.

[0010] Furthermore, the magnetron target also includes a microcontroller, the magnetic shielding louvers and the magnetron system are respectively connected to the microcontroller, and the microcontroller is used to control the opening and closing of the magnetic shielding louvers and the operation of the magnetron system.

[0011] Furthermore, the magnetic control system includes a plurality of magnetic modules, and the plurality of magnetic modules are respectively used to construct magnetic fields of different element regions of the multi-element splicing target; and the plurality of magnetic modules are respectively permanent magnets of different strengths.

[0012] Furthermore, the magnetron system can rotate around its own central axis to adjust permanent magnets of different strengths to corresponding target surface areas.

[0013] Furthermore, the opening and closing modes of the magnetic shielding louvers include rotation and telescopic movement; the opening and closing characteristics of the magnetic shielding louvers include linear gradual opening and closing, periodic opening and closing, and timed and fixed angle / length opening and closing.

[0014] According to another aspect of the present invention, a sputtering method for preparing multi-element composite thin films is provided, wherein the sputtering method adopts the magnetron target for preparing multi-element composite thin films as described above to prepare multi-element composite thin films; wherein, the strength of the magnetic field in each area of ​​the target surface is controlled by adjusting the degree of opening and closing of the magnetic shielding louvers, thereby affecting the sputtering intensity of each element, thereby adjusting the composition and relative content of the elements of the film layer to be prepared.

[0015] Furthermore, by adjusting the opening and closing degree of the magnetic shielding shutters and rotating the different strength magnetic modules of the magnetron system to different positions, the strength of the magnetic field in each area of ​​the target surface can be controlled, thereby affecting the sputtering intensity of the corresponding elements in each area of ​​the multi-element splicing target, thereby achieving the connection adjustment of the film layer components and the relative content of the elements.

[0016] In general, compared with the prior art, the above technical solutions conceived by the present invention mainly have the following beneficial effects in the magnetron target and sputtering method for preparing multi-element composite thin films provided by the present invention:

[0017] 1. The present invention controls the magnetic field range and intensity by opening and closing magnetic shielding shutters, thereby adjusting the discharge area and discharge intensity of the target surface, and can realize single-target multi-element metal co-sputtering and alternate sputtering to prepare a variety of functional coatings and layered structures.

[0018] 2. The present invention can preset the opening and closing mode of the magnetic shielding louvers according to the process and adjust the film components during the deposition process, which has high flexibility.

[0019] 3. The magnetic shielding louvers are located in the cooling water channel. When the magnetic shielding louvers are opened, the cooling water is disturbed when flowing through the louvers, and the flow is transformed into turbulent flow to enhance heat transfer and enhance the cooling effect of the target surface.

[0020] 4. Each module of the magnetron system can be set with magnets of different strengths according to needs. The whole system can rotate around the central axis and move to different areas in coordination with the opening and closing of magnetic shielding shutters during the coating process. This can expand the adjustment range of the target surface magnetic field strength, adapt to the magnetic field strength required by different target elements, and further expand the scope of application of the magnetron target. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic structural diagram of a magnetron target for preparing a multi-element composite thin film provided by the present invention;

[0022] Figure 2 (a) and (b) are Figure 1 Schematic diagram of the rotation and telescopic opening and closing of the magnetic shielding shutters of the magnetron target for preparing multi-element composite thin films;

[0023] Figure 3 yes Figure 1The schematic diagram of the structure of the spliced ​​target and magnetic module of the magnetron system for preparing multi-element composite thin films; A, B, C, and D represent the element areas of the spliced ​​target respectively; Ⅰ, Ⅱ, Ⅲ, and Ⅳ represent strong and weak magnetic modules respectively;

[0024] Figure 4 (a) and (b) are the effects of the magnetic shielding shutter switch on the magnetic field intensity on the target surface.

[0025] In all the drawings, the same reference numerals are used to denote the same elements or structures, wherein: 10 - multi-element spliced ​​target, 20 - cooling water system, 30 - magnetron system, 210 - cooling water channel, 220 - magnetic shielding louvers. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0027] See also Figure 1 , Figure 2 and Figure 3 The present invention provides a magnetron target for preparing a multi-element composite thin film, the magnetron target comprising a multi-element spliced ​​target 10, a cooling water system 20, a magnetron system 30 and a microcontroller, the cooling water system 20 is arranged between the multi-element spliced ​​target 10 and the magnetron system 30, and the central axis of the multi-element spliced ​​target 10, the central axis of the cooling water system 20 and the central axis of the magnetron system 30 coincide.

[0028] The multi-element spliced ​​target 10 is composed of a plurality of single element target materials spliced ​​into one piece, and is a circular target or a square target.

[0029] The cooling water system 20 is located behind the multi-element splicing target 10, and includes a cooling water channel 210 and a magnetic shielding louver 220, and the magnetic shielding louver 220 is arranged in the cooling water channel 210. The magnetic shielding louver 220 is divided into multiple groups and placed in the cooling water channel 210, and has good magnetic conductivity. In this embodiment, the cooling water channel 210 is concave-shaped, and the magnetic control system 30 is partially arranged in the cavity formed by the cooling water channel 210. The multi-element splicing target 10 is opposite to the middle part of the cooling water channel 210, and at the same time is opposite to the magnetic control system 30; the magnetic shielding louver 220 is located in the middle part of the cooling water channel 210. The magnetic shielding louver 220 and the magnetic control system 30 are respectively connected to the microcontroller, and the microcontroller is used to control the opening and closing of the magnetic shielding louver 220 and the action of the magnetic control system 30.

[0030] The magnetic control system 30 includes a plurality of magnetic modules, each of which is used to construct a magnetic field of different element regions of the multi-element spliced ​​target 10. In this embodiment, the plurality of magnetic modules are permanent magnets of different strengths, and the strong and weak magnetic modules are rotated to the corresponding target surface region according to the needs; the magnetic control system 30 can rotate around its own central axis to adjust the permanent magnets of different strengths to the corresponding target surface region.

[0031] The magnetic shielding shutter 220 can be retracted and rotated relative to the cooling water channel 210. When the magnetic shielding shutter 220 is opened, the magnetic module generates a magnetic field on the corresponding target surface, and the elements in the corresponding target surface area are sputtered. The magnetic shielding shutter 220 can disturb the flow in the cooling water channel 210, enhance heat exchange, and enhance target cooling. When the magnetic shielding shutter 220 is closed, the magnetic field is shielded, and the elements on the target surface in the upper area cannot glow discharge. The magnetron target can realize the sputtering of each element of the target material together and in turn.

[0032] By adjusting the opening and closing degree of the magnetic shielding louvers 220, the magnetic field strength in each area of ​​the target surface is controlled, affecting the sputtering intensity of each element, thereby adjusting the composition and relative content of the elements in the film layer to be prepared. The multi-element composite film includes a gradient alloy film and a custom component multilayer film. The opening and closing methods of the magnetic shielding louvers 220 include rotation and telescopic.

[0033] The opening and closing characteristics of the magnetic shielding louvers 220 include linear gradual opening and closing, periodic opening and closing, and timing and fixed angle / length opening and closing. The magnetic control system 30 can control the magnetic field on the target surface in accordance with the opening and closing degree of the magnetic shielding louvers 220.

[0034] See also Figure 4 The present invention also provides a sputtering method for preparing a multi-element composite thin film, the sputtering method mainly comprising the following steps:

[0035] S1, fix the substrate substrate on the sample stage and set the deposition temperature of the substrate substrate.

[0036] The relative position relationship between the substrate base and the target surface of the magnetron target is that a single magnetron target is coaxially facing or multiple magnetron targets are confocal.

[0037] S2, providing the magnetron target as described above, and constructing a high vacuum environment required for magnetron sputtering.

[0038] S3, setting the initial opening and closing degree of the magnetic shielding louvers 220 in each zone, and presetting the opening and closing characteristics of the magnetic shielding louvers 220 during the coating process.

[0039] S4, adjusting the magnetic control system 30 to rotate each magnetic module to an initial position, and the microcontroller presets the rotation timing and angle of the magnetic control module and the opening and closing of the magnetic shielding shutters 220 according to process requirements.

[0040] S5, turn on the target power supply, under the action of the magnetic shielding shutters 220 and the magnetron system 30, the magnetic field strength in different areas of the target surface is different and changes with time, and the sputtering intensity of each element is different and has a preset change rule.

[0041] S6, after sputtering for a predetermined time, a multi-component multi-layer film is prepared.

[0042] The cooperation between the magnetic shielding shutters 220 and the magnetic control system 30 includes: when the shutters are fully opened and the strong magnetic module is combined, the magnetic field intensity of the target surface in this area is the largest, and when the shutters are fully closed and the weak magnetic module is combined, the magnetic field intensity of the target surface in this area is extremely small. The different opening and closing degrees of the magnetic shielding shutters 220 and the combination of magnetic modules with different strengths can make the magnetic field intensity of the target surface in each area continuously adjustable within the maximum and minimum range.

[0043] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A magnetron target for preparing multi-element composite thin films, characterized in that: The magnetron target comprises a multi-element spliced ​​target, a cooling water system and a magnetron system, wherein the cooling water system is arranged between the multi-element spliced ​​target and the magnetron system; the cooling water system comprises a cooling water channel and magnetic shielding louvers, wherein the magnetic shielding louvers are arranged in the cooling water channel and are used for selectively magnetically shielding the target surface of the multi-element spliced ​​target; The magnetic shielding louvers correspond to the positions of the multi-element spliced ​​target, and the magnetic shielding louvers can rotate and extend relative to the cooling water channel; the magnetron target controls the strength of the magnetic field in each area of ​​the target surface of the multi-element spliced ​​target through the rotation and extension of the magnetic shielding louvers, thereby adjusting the sputtering intensity of the corresponding elements in each area of ​​the multi-element spliced ​​target.

2. The magnetron target for preparing a multi-element composite thin film according to claim 1, characterized in that: The central axis of the multi-element spliced ​​target, the central axis of the cooling water system and the central axis of the magnetron system coincide with each other.

3. The magnetron target for preparing a multi-element composite thin film according to claim 1, characterized in that: The multi-element spliced ​​target is composed of a plurality of single element target materials spliced ​​into one piece, and is a circular target or a square target.

4. The magnetron target for preparing a multi-element composite thin film according to claim 1, characterized in that: The cooling water channel is in a concave shape, the magnetic control system is partially arranged in the cavity formed by the cooling water channel, the multi-element spliced ​​target is opposite to the middle of the cooling water channel; the magnetic shielding louver is located in the middle of the cooling water channel.

5. The magnetron target for preparing multi-element composite thin films according to claim 4, characterized in that: The magnetron target further includes a microcontroller, the magnetic shielding louvers and the magnetron system are respectively connected to the microcontroller, and the microcontroller is used to control the opening and closing of the magnetic shielding louvers and the action of the magnetron system.

6. The magnetron target for preparing multi-element composite thin films according to claim 1, characterized in that: The magnetic control system includes a plurality of magnetic modules, and the plurality of magnetic modules are respectively used to construct magnetic fields of different element regions of the multi-element splicing target; and the plurality of magnetic modules are respectively permanent magnets of different strengths.

7. The magnetron target for preparing a multi-element composite thin film according to claim 6, characterized in that: The magnetic control system can rotate around its own central axis to adjust permanent magnets of different strengths to corresponding target surface areas.

8. The magnetron target for preparing a multi-element composite thin film according to claim 5, characterized in that: The opening and closing modes of the magnetic shielding louvers include rotation and telescopic movement; the opening and closing characteristics of the magnetic shielding louvers include linear gradual opening and closing, periodic opening and closing, and timing, fixed angle, and fixed length opening and closing.

9. A sputtering method for preparing a multi-element composite thin film, characterized in that: The sputtering method is to prepare a multi-element composite film using the magnetron target for preparing a multi-element composite film as described in any one of claims 1 to 8; wherein, the magnetic field strength in each area of ​​the target surface is controlled by adjusting the degree of opening and closing of the magnetic shielding louvers, thereby affecting the sputtering intensity of each element, thereby adjusting the composition and relative content of the elements in the film layer to be prepared.

10. The sputtering method for preparing a multi-element composite thin film according to claim 9, characterized in that: By adjusting the degree of opening and closing of the magnetic shielding shutters and rotating the different strength magnetic modules of the magnetron system to different positions, the strength of the magnetic field in each area of ​​the target surface can be controlled, thereby affecting the sputtering intensity of the corresponding elements in each area of ​​the multi-element splicing target, and realizing the connection adjustment of the film layer components and the relative content of the elements.

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