JPH02194172A - Coating method - Google Patents

Abstract

PURPOSE:To efficiently and uniformly perform dry coating for material to be treated by providing four pieces of targets to both upper and lower sides and left and right sides at the prescribed intervals apart from the material to be treated and sticking the atoms sputtered from these targets on the material and resticking the unstuck atoms on any one of the above-mentioned targets. CONSTITUTION:The inside of main body 1 is exhausted at high vacuum and thereafter gaseous Ar is introduced thereinto. Then DC or high frequency is impressed to the targets 2a-2d which are arranged to both upper and lower sides and left and right sides at prescribed intervals apart from the material 3 to be treated. Thereby glow discharge is caused and the targets 2a-2d are beaten by Ar ions in the generated plasma. The atoms constituting the target substance are sputtered and stuck on the surface of the material 3 and film formation is performed. As a result, even when a wire rod, a bar rod and a tubular material are utilized for the material 3, a plated film is uniformly formed on the external surfaces thereof. Further even when the target atom sputtered from one target 2a is not caught on the material 3, this target atom reaches the targets 2b-2d of the opposite side and both sides and is caught and reutilized. Therefore the availability of the target material is enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a coating method particularly suitable for continuous coating of wire rods, rods, tubes, etc.

In recent years, many dry brating methods such as vacuum evaporation, ion blating, and sputtering have been developed. This method has advantages such as being able to plate the objects to be processed, greatly expanding the range of objects that can be processed, being able to perform plating that cannot be achieved with wet methods, and being able to perform high-performance plating and thin film formation. The drive rating method is rapidly spreading, and is used in semiconductors, optoelectronics, recording materials, home appliances, automobiles, tools,
It has become a key technology in almost all fields of industry, including decorative items.

However, since the dry brating method uses a vacuum system, the equipment is expensive and complicated.

Furthermore, there are still major problems from an industrial standpoint, such as the rate of plating formation being not necessarily fast.

In particular, when the object to be treated is fiber, wire, strand, other wire rod, rod, tube material, etc., the efficiency with which the plating material is collected on the object when forming a film on the outer peripheral surface of the object is significant. It is difficult to coat the outer peripheral surface of the object (wire rod, bar, pipe, etc.) with a uniform thickness, and if you try to coat at a high speed of several tens of meters per minute or more, Problems such as the size of the equipment arise.

That is, in a conventional sputtering apparatus, a target and a workpiece are arranged facing each other in the main body of the sputtering apparatus, and the target is connected as a cathode to a DC power source or a high frequency power source. When plating is carried out using a wire, if the object to be processed is a wire, rod, pipe, etc., target atoms will adhere to the side facing the target and form a film, but there will be sufficient plating on the back side. In order to prevent the target atoms from adhering to the surface, making it difficult to plate the plate uniformly, and to form a sufficient film on the back surface, after plating the surface facing the target, rotate the object to plate the back surface. In addition to the problem of having to face the target and perform plating again, most of the target atoms (plating material) are not collected by the object to be processed and are scattered and lost, so the utilization efficiency of the target material is extremely low. The problem is that it's bad.

This situation is the same even when a vacuum evaporation method, an ion brating method, etc. are adopted as the dry brating method.

Therefore, a method for efficiently, uniformly and economically dry plating wire rods, rods, pipes, etc. is desired.

A coaxial hollow sputtering method is conventionally known as a method that slightly meets this purpose. In this method, a target is attached to the inner wall of a cylindrical container to serve as a cathode, and if necessary, a magnetic field is applied from outside the cylindrical container to perform dry plating on the workpiece placed inside the container. At this time, it is possible to perform plating while continuously moving the object to be treated in the axial direction, and the uniformity of the film thickness and the efficiency of use of the target material are good, but it is troublesome to replace and create the target, and it is costly. It also has the disadvantage of being expensive.

Furthermore, it is an effective method to perform sputtering by arranging a pair of targets facing each other and placing the object to be processed between them (Japanese Patent Application No. 139446/1982), but this method also allows atoms ejected from both targets to Since the particles are directed not only toward the object to be treated but also on both sides, the efficiency of capturing the ejected atoms is still low.

The present invention was made in view of the above circumstances, and is directed to a wire rod.

It is an object of the present invention to provide a coating method that can efficiently and uniformly dry-coat objects to be treated such as rods and pipes, and that also has good target material usage efficiency and ejected atom collection efficiency, and is also excellent in economical efficiency. purpose.

r! S-I! In order to achieve the above object, the present invention arranges four targets on the upper, lower, right and left sides of the object to be processed, and has four targets separated from the object by a predetermined distance. Provided is a coating method characterized in that each of the atoms attached to the object to be treated is attached to the object to be treated, and the atoms not attached to the object to be treated are redeposited to any one of the upper, lower, left, and right targets.

In this case, the present invention can be suitably applied to coating wires, rods, and pipes; however, in this case, a plurality of wires,
It is possible to surface-treat a plurality of wire rods, rods, or tube materials at the same time by arranging the rods or tubes at a predetermined distance from each other, and by continuously moving the object to be treated. It is effective to coat the object continuously. Note that the cross-sectional shapes of the wire, rod, and tube are not particularly limited.

Further, the present invention can be suitably applied to a sputtering method, particularly a magnetron sputtering method, but in this case, magnets are arranged behind four targets so that the same poles of the magnets of the mutually opposing targets face each other. death,
It is preferable that coating be performed in a state in which the lines of magnetic force formed near the surfaces of the targets facing each other are repelled from each other.

■-Sato According to the present invention, four targets are placed at the top, bottom, left and right of the workpiece with a predetermined distance from the workpiece, and the atoms ejected from these targets are attached to the workpiece. By applying a film, target atoms are applied to the entire object at the same time from the targets placed on the top, bottom, left and right of the object. Dry plating is performed efficiently and uniformly even when the target material is This increases the efficiency of use of atoms, and the efficiency of capturing atoms is very high. In this case, coating is carried out while continuously moving the object to be treated, and when coating a plurality of wire rods, rods, or tubes as objects to be treated, these are arranged at a predetermined distance from each other.

From the viewpoint of productivity, it is preferable to coat a plurality of these wires, rods, or tubes at the same time.

Furthermore, when the present invention is applied to the magnetron sputtering method, magnets are arranged behind each of the four targets so that the same poles of the magnets of the opposing targets face each other, and the magnets are placed near the surfaces of these mutually opposing targets. By performing coating with the magnetic lines of force repelled from each other, a dense plasma region is formed near the surface of each target, which increases the sputtering rate.

The erosion and consumption of sputter becomes uniform, and the utilization efficiency of sputter is further increased.

An embodiment of the present invention will be described below with reference to the drawings.

Figure 1 shows an example of an apparatus used for carrying out the present invention. In the figure, 1 is a main body of a magnetron sputtering apparatus, and within this main body 1 four targets 2a, 2b, 2c,
2d are placed above, below, left and right of the workpiece 3 so as to surround the workpiece 3 and spaced apart from the workpiece 3 by a predetermined distance.

Here, in the magnetron sputtering method, as shown in FIG. 2, a magnet (permanent magnet or electromagnet) 4 is placed behind the target 2, and due to the placement of the magnet 4, it is shown as a broken line near the surface of the target 2. Magnetic lines of force are formed. Then, when a negative potential is applied to target 2, the electrons move at high speed in a cycloid along the magnetic field lines, collide with a rare gas such as argon, and separate into ions and electrons, targeting a high-density plasma region. At the same time, the positive ions in the plasma collide inelastically with the target 2, which is given a negative potential, and knock out atoms of the target material, and as described above, the shot out target atoms strike the workpiece. Films are formed by adhesion, and one of the factors that governs the film formation speed in film formation using such magnetron sputtering methods is how efficiently a dense plasma region can be created near the target 2. Therefore, it is effective to increase the target-parallel component of the lines of magnetic force. Also, target 2
As the plating progresses, if the erosion is concentrated in one part as shown by the dotted chain line in Figure 2, the cross section will be eroded and consumed in a conical shape, and if the top reaches the back surface of target 2, target 2 However, if the target-parallel component of the magnetic field lines increases and a plasma-dense region is formed near the target 2, the sputtering speed will increase and the target will erode and wear out into a dish-shaped cross section. The manner in which the target is consumed becomes more uniform, and the efficiency of use of the target material is increased.

As shown in FIG. 1, in this magnetron sputtering method, four targets 2a, 2
Magnets 4a, 4b, 4c are behind b, 2c, 2d, respectively.
, 4d of the targets 2a and 2b and 2c and 2d facing each other with the same polarity of the magnets 4a and 4b and 4c and 4d (i.e. S
When the magnetic force lines formed near the surfaces of the targets 2a, 2b, 2c, and 2d repel each other, the magnetic force lines of the targets 2a, 2b, and 2d repel each other. The parallel component to 2c, 2d increases, which causes both targets 2a, 2b.

A dense plasma region is formed on the surfaces 2c and 2d.

Note that in this example, the target 2a.

2b, 2c, and 2d can be cathodes, and the object to be treated 3 can be connected to a DC high-voltage power source as an anode, but the present invention can also be suitably applied to a high-frequency sputtering method, and in this case, a high-frequency power source is used.

When plating the workpiece 3 using the above device,
After evacuating the inside of the main body 1 to a high vacuum according to a conventional method, argon gas is introduced, usually 1 x 10-3 to I x 10-'
Torr degree) 1st then target 2a.

A direct current or high frequency is applied to 2b, 2c, and 2d to cause glow discharge and generate plasma, which causes argon ions in the plasma to reach the target 2a.
, 2b, 2c, and 2d are respectively hit to eject atoms constituting the target material from these targets 2a, 2b, and 2ct2d, and these target atoms adhere to the surface of the object to be processed, thereby forming a film. .

In this case, targets 2a, 2b, 2c, and 2d are arranged on the top, bottom, left, and right sides of the workpiece 3, respectively, and target atoms adhere to the entire workpiece 3 from the top, bottom, left, and right of the workpiece 3, so that Even if the object 3 is a wire, rod, or tube, a uniform plating film is quickly formed on the outer peripheral surface of the material, and continuous coating is also possible by continuously moving the object 3 to be treated. Also, one target 2
Even if the target atoms ejected from a are not captured by the target 2 on the opposite side and both sides,
b, 2c, and 2d, where they are collected and reused, increasing the utilization efficiency of the target material.

Here, when a wire, a bar, or a tube is used as the object to be processed, the targets 2a and 2b face each other.

It is preferable to arrange a plurality of objects to be processed at a predetermined distance between 2c and 2d, and to plate a plurality of objects at the same time. It is possible to improve the adhesion efficiency of the material to the object to be treated.

Therefore, according to the embodiment shown in FIG. 1, the film formation rate is improved and the targets 2a, 2b are improved.

2c and 2d are eroded and consumed in a dish-shaped cross section as shown by the dashed line in the figure, so the utilization efficiency of the target is increased and the life span is extended.

Further, in this case, electromagnets are used as the magnets 4a, 4b, 4c, and 4d, and the current given to these electromagnets is changed periodically, pulsed, or randomly, and the magnetic field formed by the electromagnets is changed periodically, pulsed, or randomly. By changing the distribution of the magnetic field near the surfaces of the targets 2a, 2b, 2c, and 2d, the erosion and consumption of the targets 2a, 2b, 2c, and 2d can be made more uniform, and the targets 2a, 2b, and 2c can be , 2d can be used more efficiently and have a longer service life.
This makes it possible to apply more uniform plating to the surface.

As explained above, according to the present invention, four targets are placed above, below, left and right of the object to be treated, and the atoms ejected from these targets are attached to the object. By forming a film, the object to be treated can be efficiently and uniformly dry-coated, and scattered atoms are collected without wastage, the target material is used efficiently, and the equipment configuration can be simplified. It is relatively simple and economically superior, and the present invention is particularly suitable for coating wire rods, rods, pipes, etc., such as uniform coating of aluminum etc. on glass fibers,
Coating of metals, metal oxides, metal nitrides, etc. on the outer surface of plastic tubes.

Cobalt coating on steel cords and organic fiber cords, superconducting metals on copper wires, carbon fibers, etc.
Coating of intermetallic compounds and superconducting ceramics can be easily performed.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of an example of a magnetron sputtering apparatus used for carrying out the present invention, and FIG. 2 is a schematic cross-sectional view showing a conventional magnetron sputtering apparatus. 1... Sputtering device main body 2a, 2b, 2c, 2d...
Target 3...Things to be processed 4 a, 4 b, 4 c, 4 d - Magnet applicant Brideston Co., Ltd. Agent Patent attorney Takashi Kojima Figure 1 procedure amendment (voluntary) March 15, 1989 Japanese Patent Application No. 11680 of 1999 2, Title of Invention Coating Method 3, Relationship with the Amendment Person Case

Claims (1)

[Claims] 1. Arrange four targets on the top, bottom, left, and right sides of the object to be processed at a predetermined distance from the object to be processed, and attach the atoms ejected from these four targets to the object to be processed, and A coating method characterized by re-attaching atoms that are not attached to an object to targets either above, below, left or right.