CN117344279A - A magnetic control system for large-area thin film preparation - Google Patents

Abstract

The invention belongs to the technical field related to magnetron sputtering film deposition, and discloses a magnetron system for preparing a large-area film. The magnetron system comprises a deposition substrate and a movable target, wherein the deposition substrate and the movable target are oppositely arranged, the movable target comprises a target material, a gas supply ring and a dynamic magnet, the target material is connected with an electric field cathode to enable the target material to serve as a cathode target material of magnetron sputtering, the gas supply ring is used for supplying reaction gas to the periphery of the target material, and the dynamic magnet is arranged in the movable target and is used for providing a magnetic field with an adjustable magnetic field range around the target material; when the center of the moving target and the center of the deposition substrate are on the same horizontal line, the magnetic field range is minimum, the area of the deposition spot formed on the deposition substrate is minimum, and when the moving target moves away from the center of the deposition substrate along the radial direction of the deposition substrate, the magnetic field range is gradually increased, and the area of the deposition spot formed on the deposition substrate is gradually increased. The invention solves the problem that the deposition uniformity of the preparation of the large-area film is difficult to regulate and control in the prior art.

Description

A magnetic control system for large-area thin film preparation

Technical field

The invention belongs to the technical field related to magnetron sputtering thin film deposition, and more specifically, relates to a magnetron system for large-area thin film preparation.

Background technique

Magnetron sputtering is a metal and compound thin film deposition technology. The films prepared by this technology have high uniformity and high density, so they are widely used in integrated circuits, wear-resistant and anti-corrosion coatings, optical coatings, and architectural glass. Achieve low-cost large-scale industrial production in areas such as large-area coatings and photovoltaic solar cells. The magnetron sputtering process is carried out in a high vacuum environment. The cathode target is bombarded by high-energy argon ions generated in the glow discharge plasma, sputtering out a large number of target particles. Finally, the target metal is deposited on the surface of the substrate to form a film layer. . Compared with thin film deposition technologies such as chemical vapor deposition and multi-arc ion plating, magnetron sputtering has the advantages of high speed, low temperature and low damage.

With the development of semiconductor and other industries, the preparation of large-area, high-quality film layers has become the basis for the development of next-generation electronic and optoelectronic devices. Magnetron sputtering technology to deposit large-area uniform films has become the key to technological development. Large-area films are usually composed of a variety of elements. According to requirements, they can be prepared into materials with properties such as high temperature resistance, corrosion resistance, oxidation resistance, and high hardness. They can be used in high-quality organic semiconductor films, high-speed aircraft thermal protective coatings, and Solar cell light-absorbing layer, etc. The key to the preparation of large-area films is to maintain uniformity of film deposition over a large area. However, the sizes of the substrate table and target table in traditional magnetron sputtering are limited. Existing improvement technologies include increasing the size of the substrate table and target table at the same time, increasing the And move the substrate stage, etc. These methods have problems such as bulky equipment, low production efficiency, and difficulty in ensuring coating uniformity. The complexity of the system and the low quality of the film layer limit its industrial application. Therefore, how to design a magnetron system and sputtering method that can achieve uniform preparation of large-area thin films is an urgent problem that those skilled in the art need to solve.

Contents of the invention

In view of the above defects or improvement needs of the prior art, the present invention provides a magnet control system for large-area thin film preparation, which solves the problem in the prior art that the deposition uniformity of large-area thin film preparation is difficult to control.

In order to achieve the above object, according to the present invention, a magnet control system for large-area thin film preparation is provided. The magnet control system includes a deposition substrate and a moving target, wherein,

The deposition substrate is arranged opposite to the moving target. The deposition substrate can rotate around its own center. The moving target includes a target material, a gas supply ring and a dynamic magnet. The target material is arranged on the top of the moving target. , the target is connected to the electric field cathode so that the target serves as a cathode target for magnetron sputtering, the gas supply ring is used to provide reactive gas around the target, and the dynamic magnet is arranged on the moving target , used to provide a magnetic field with an adjustable magnetic field range around the target;

When the center of the moving target and the center of the deposition substrate are on the same horizontal line, the magnetic field range is the smallest and the area of the deposition spot formed on the deposition substrate is the smallest. When the moving target moves along the deposition When the radial direction of the substrate moves away from the center of the circle of the deposition substrate, the magnetic field range gradually increases, and the area of the deposition spot formed on the deposition substrate gradually increases;

During the magnetron sputtering deposition process, the rotation of the deposition substrate and the movement of the moving target cause the deposition spot to completely scan the surface of the deposition substrate. The rotation speed and moving speed are adjusted to control the position of the deposition spot and the deposition time, thereby achieving a uniform film over a large area. deposition.

Further preferably, the dynamic magnet includes an inner magnet and an outer magnet, the inner magnet is fixed at the center of the moving target, and the outer magnet moves away from the deposition substrate along the radial direction of the moving target along with the moving target. The circular center motion of the deposition substrate gradually moves away from the inner magnet, thereby causing the magnetic field range to gradually increase.

Further preferably, the magnetic pole directions of the inner magnet and the outer magnet are opposite. When the magnetic field range shrinks, the distance between the inner magnet and the outer magnet decreases. When the magnetic field range expands, the distance between the inner magnet and the outer magnet increases. increase.

Further preferably, the dynamic magnet includes a plurality of bar magnets arranged in parallel. When the magnetic field range shrinks, the outer magnet moves parallel toward the inner magnet. When the magnetic field range expands, the outer magnet moves away from the inner magnet. The direction of the inner magnet moves parallel.

Further preferably, the outer magnets are distributed in an annular shape, and the inner magnets are arranged at the center of the outer magnets. When the magnetic field range shrinks, the outer magnets move closer to the inner magnets along the radius of the annular ring. When the magnetic field range expands, the outer magnet moves away from the inner magnet along the radius of the ring.

Further preferably, the gas supply ring is set outside the moving target, and the reaction gas flows out of the gas supply ring.

Further preferably, the gas supply ring and the moving target are coaxial.

Further preferably, the reaction gas is one or more of argon gas or gases required for magnetron sputtering reaction.

Further preferably, the diameter of the deposition substrate is larger than the diameter of the moving target.

Further preferably, the deposition substrate and the moving target are arranged in a vacuum chamber.

Generally speaking, compared with the prior art, the above technical solution conceived by the present invention has the following beneficial effects:

1. The present invention realizes adjustment of the magnetic field range by shrinking or expanding the magnet. Since the plasma generated by sputtering on the target surface is bound by the magnetic field, the plasma distribution range can be controlled, thereby changing the size of the deposition spot where the target atoms are deposited on the substrate. ;

2. The gas supply ring of the present invention is distributed around the target material to pass in the argon gas required for sputtering. Compared with the traditional gas inlet provided on the cavity wall, this arrangement increases the concentration of argon atoms near the target surface, which is conducive to sputtering. The reaction overcomes the problems of uneven distribution of argon gas in the cavity and low concentration of argon atoms near the target surface in traditional large-area thin film deposition, which makes it impossible to stably maintain glow discharge;

3. The present invention can preset the periodic rotation characteristics of the substrate and the linear reciprocating motion of the moving target according to the process, jointly adjust the sputtering duration of each area through the movement speed and rotation speed, and control the film thickness at different positions on the large-area substrate, which can be prepared High uniformity films and graded thickness films.

Description of drawings

Figure 1 is a schematic structural diagram of a magnet control system for large-area thin film preparation constructed in accordance with a preferred embodiment of the present invention;

Figure 2 is a schematic diagram of the linear motion of the moving target and the contraction and expansion state of the dynamic magnet constructed in accordance with the preferred embodiment of the present invention;

Figure 3 is a schematic diagram of the deposition spots formed on the substrate in the contraction and expansion states of the dynamic magnet constructed according to the preferred embodiment of the present invention;

Figure 4 is a schematic structural diagram of a dynamic magnet constructed in accordance with a preferred embodiment of the present invention. Throughout the drawings, the same reference numbers refer to the same elements or structures, wherein:

10-Deposition substrate, 20-Small deposition spot, 21-Large deposition spot, 100-Moving target, 110-Gas supply ring, 120-Outer magnet, 130-Inner magnet, 140-Target.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described here 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.

Referring to Figure 1, the present invention proposes a magnet control system for large-area thin film preparation. The system includes a deposition substrate 10 and a moving target 100; the deposition substrate 10 rotates around a central axis and the rotation speed is adjustable; the moving target 100 It consists of a gas supply ring 110, a target material 140, and a dynamic magnet. The moving target 100 moves linearly along the radius direction of the substrate, and the speed is adjustable; the gas supply ring 110 is coaxial with the moving target 100, and the argon gas required for sputtering or Reactive gas; the dynamic magnet includes an outer magnet 120 and an inner magnet 130, and the outer magnet 120 can continuously shrink or expand.

As shown in Figure 2, when the outer magnet 120 is in a contracted state, the discharge range on the target surface is small, and small deposition spots 20 are formed on the deposition substrate 10; the movable target 100 moves upward, and the outer magnet 120 moves outward away from the inner magnet, and the target surface The discharge range expands and large deposition spots 21 are formed on the deposition substrate 10 . The rotation of the deposition substrate 10 and the linear motion of the moving target 100 allow the deposition spot to completely scan the surface of the deposition substrate, and the rotation speed and moving speed are adjusted to control the position of the deposition spot and the deposition time, thereby achieving uniform deposition of a large-area thin film. As shown in Figure 3, it can be seen from the figure that when the moving target moves in the radial direction from the position facing the center of the substrate, the external magnet gradually expands outwards and the deposition spot gradually increases. The farther away from the center of the circle, the smaller the area to be deposited on the substrate. The larger the deposition spot is, the gradually increasing deposition spot of the present invention just meets this demand. This deposition method makes the deposition spot on the outer edge of the substrate cover a larger area in a single linear motion, thereby improving the uniformity of multiple depositions.

The deposition substrate 10 can move along the central axis to adjust the distance between the substrate and the target, and the rotation speed of the deposition substrate 10 is adjustable within one rotation cycle.

The linear reciprocating motion modes of the moving target 100 include constant speed, constant variable speed, variable acceleration and variable deceleration.

The gas supply ring 110 is distributed around the target 140, and the gas supplied includes argon gas and gases required for reactive sputtering.

The outer magnet 120 can continuously shrink or expand to control the area of the sputtering area on the target surface, thereby continuously adjusting the size of the deposition spot.

As shown in Figure 4, in one embodiment of the present invention, the outer magnets 120 are distributed in a circular shape, and the inner magnet 130 is arranged at the center of the outer magnet. When the magnetic field range shrinks, the outer magnet 120 moves in the direction of the radius of the ring toward the direction closer to the inner magnet 130. When the magnetic field range expands, the outer magnet 120 moves away from the inner magnet 130 along the radial direction of the ring.

Large-area thin films are prepared based on the above magnetic control system for large-area thin film preparation; wherein, the deposition position is controlled by adjusting the periodic rotation characteristics of the rotation process of the substrate 10 and the linear reciprocating motion of the moving target 100, and its rotation speed and moving speed determine the deposition thickness in different areas.

The specific implementation steps of the working process of the magnetic control system of the present invention are as follows:

S1, fix the deposition substrate, set the deposition temperature, and build the high vacuum environment required for magnetron sputtering.

S2, set the periodic rotation characteristics of the deposition substrate.

S3, set the initial position of the moving target and preset its linear reciprocating motion mode.

S4, adjust the initial position of the dynamic magnet so that the moving target and the magnet cooperate to build the expected deposition area.

S5, turn on the target power supply, and after sputtering for a predetermined time, prepare a large-area thin film.

The cooperation between the movable target 100 and the external magnet 120 is as follows: when the movable target 100 moves toward the center of the substrate, the external magnet 120 shrinks and instead expands outward, which can cause the deposition spot area to continuously change with the radius of the substrate to achieve uniform deposition of a large-area film. .

The invention adjusts the position of the discharge area through the rotation of the substrate and the linear motion of the moving target, so that the deposition spot can cover a large area of the substrate, and can realize the preparation of large-area thin films with small magnetron targets; the dynamic magnet shrinks and expands with the position of the moving target, and the moving target When coaxial with the substrate, the external magnet shrinks, and gradually expands when moving along the radius of the substrate, thereby expanding the deposition spot area toward the edge of the substrate, adapting to the deposition of thin films on circular substrates, and significantly improving the uniformity of large-area coatings. .

It is easy for those skilled in the art to understand that the above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements, etc., made within the spirit and principles of the present invention, All should be included in the protection scope of the present invention.

Claims (10)

1. A magnet control system for large-area thin film preparation, characterized in that the magnet control system includes a deposition substrate (10) and a moving target (100), wherein, The deposition substrate (10) is arranged opposite to the moving target (100). The deposition substrate (10) can rotate around its own center. The moving target (100) includes a target material (140), a gas supply ring ( 110) and a dynamic magnet, the target (140) is arranged on the top of the moving target (100), the target (140) is connected to the electric field cathode so that the target (140) serves as the cathode of magnetron sputtering Target material (140), the gas supply ring (110) is used to provide reaction gas around the target material (140), the dynamic magnet is provided in the moving target (100), and is used to move the target material around the target material (140). A magnetic field with an adjustable magnetic field range is provided around the material (140); When the center of the moving target (100) and the center of the deposition substrate (10) are on the same horizontal line, the magnetic field range is the smallest, and the area of the deposition spot formed on the deposition substrate (10) is the smallest, When the moving target (100) moves away from the center of the deposition substrate (10) along the radius direction of the deposition substrate (10), the magnetic field range gradually increases. ) The area of sedimentation spots formed on the surface gradually increases; During the magnetron sputtering deposition process, the rotation of the deposition substrate (10) and the movement of the movable target (100) cause the deposition spot to completely scan the surface of the deposition substrate (10), and the rotation speed and movement speed are adjusted to control the position and position of the deposition spot. deposition time, thereby achieving uniform deposition of thin films over a large area. 2. A magnet control system for large-area thin film preparation as claimed in claim 1, characterized in that the dynamic magnet includes an inner magnet (130) and an outer magnet (120), and the inner magnet (130) Fixed at the center of the moving target (100), the external magnet (120) moves away from the deposition substrate (10) along the radial direction of the deposition substrate (10) as the moving target (100) The center of the circle moves gradually away from the inner magnet (130), so that the magnetic field range gradually increases. 3. A magnet control system for large-area thin film preparation according to claim 1 or 2, characterized in that the magnetic pole directions of the inner magnet (130) and the outer magnet (120) are opposite, and when the magnetic field range shrinks, , the distance between the inner magnet (130) and the outer magnet (120) decreases, and when the magnetic field range expands, the distance between the inner magnet (130) and the outer magnet (120) increases. 4. A magnetic control system for large-area thin film preparation as claimed in claim 3, characterized in that the dynamic magnet includes a plurality of bar magnets arranged in parallel, and when the magnetic field range shrinks, the external magnet ( 120) Move parallel to the direction closer to the inner magnet (130). When the magnetic field range expands, the outer magnet (120) moves parallel to the direction away from the inner magnet (130). 5. A magnet control system for large-area thin film preparation according to claim 3, characterized in that the outer magnets (120) are distributed in a circular shape, and the inner magnets (130) are arranged on the outer magnets. At the center of the magnet (120), when the magnetic field range shrinks, the outer magnet (120) moves toward the inner magnet (130) along the radius of the ring. When the magnetic field range expands, the outer magnet (120) moves along the radius of the ring. The radial direction of the ring moves away from the inner magnet (130). 6. A magnetic control system for large-area thin film preparation according to claim 1 or 2, characterized in that the gas supply ring (110) is set outside the moving target (100), and the reaction gas is supplied from the gas supply ring. flows out of ring (110). 7. A magnet control system for large-area thin film preparation according to claim 6, characterized in that the gas supply ring (110) and the moving target (100) are coaxial. 8. A magnetron system for large-area thin film preparation as claimed in claim 1 or 2, characterized in that the reaction gas is argon or one of the gases required for the magnetron sputtering reaction or Various. 9. A magnet control system for large-area thin film preparation according to claim 1, characterized in that the diameter of the deposition substrate (10) is larger than the diameter of the moving target (100). 10. A magnet control system for large-area thin film preparation according to claim 1, characterized in that the deposition substrate (10) and the moving target (100) are arranged in a vacuum chamber.