JPH0641737A - Magnetron sputtering device - Google Patents

Abstract

PURPOSE:To uniformalize the sputtering in the terminal part of a target by joining a center magnet and edge magnets in such a manner that the magnetic poles of these magnets are opposed from each other. CONSTITUTION:The edge magnets 4 are arranged at the same length on both sides of the center magnet 5 opposite from the magnetization direction of the center magnet. Magnetic materials 10, 12 having >=100 magnetic permeability magnetically connect permanent magnets 4 and 5. The comparison made for the distribution of the magnetic fields between the terminal part of the target to be installed between the magnetic materials 13 and 14 and the central part thereof reveals that the difference therebetween is confined to about 10% at the max. value. The directions of the magnetic fields in the central part and the terminal part are the same and the uniformity in 80% region of the target is maintained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetron sputtering apparatus, and more particularly to a magnetron sputtering apparatus with improved utilization efficiency of a non-magnetic target.

[0002]

2. Description of the Related Art As shown in FIG. 7, a conventional general magnetron sputtering apparatus has a substrate holder 1 attached to an upper portion of a magnetron sputtering container and a lower portion of the substrate holder 1 for sputtering. It has a substrate 2 on which particles are deposited, a target 3 arranged below the substrate 2 on which the particles are sputtered, and permanent magnets (or electromagnets) 4 and 5 placed below the target 3 with a slight distance. In the figure, 6 is a line of magnetic force, 9 is a state (erosion) of a target after being sputtered, 7 is sputtered particles, 8 is an inert gas (Ar or the like),
Indicates a yoke (magnetic material) of a magnetic circuit connecting the magnets.

As described above, in the magnetron sputtering apparatus, a permanent magnet (or electromagnet) is installed below the target so that a magnetic field is generated on the surface of the target 3, and the magnetic field forms plasma directly above the target. The target is sputtered by ionized sputter gas particles trapped in plasma, and the sputtered particles are configured to fly onto a substrate disposed above the target.

However, the number of particles (sputtered particles) ejected from the target is proportional to the horizontal component of the magnetic field on the surface of the target, but the horizontal component of the magnetic field is not uniform, so the target is localized in the shape of a thin ring line. Had been sputtered. That is, the target only sputters an area of 20 to 30% on its surface, and the utilization efficiency of the expensive target was poor.

Therefore, the horizontal component of the magnetic field is made as uniform as possible to improve the life of the target.
5 has been proposed (FIG. 4 shows the entire target cathode, and FIG. 5 shows a cross-sectional view near the central portion thereof). That is, the target 3 is placed between the upper portions of the permanent magnets 4 and 5, the magnetic bodies 11 and 12 are located directly above the central portions and the end portions of the permanent magnets 4 and 5, and the magnetic bodies 13 and 14 are placed above them. Are arranged respectively.

[0006]

However, as shown in FIG. 6, the proposed device has two sputtering target regions (range B) which are wide and end portions (range A) along the length of the target. ), The strength of the magnetic field is improved to the same extent as the range A, but the direction Ha of the horizontal magnetic field is different from the direction Hb of the horizontal magnetic field at the central portion at the end portion (the directions of Ha and Hb are mutually different). Due to the formation of a right angle, the sputtering was not uniform and the film formation was unstable or the efficiency was low. Therefore, in order to prevent the formation of a foreign film, the end portion is often not used, and the productivity is reduced accordingly. Therefore, an object of the present invention is to provide a magnetron sputtering apparatus capable of forming a film on the entire surface of a target and having a uniform magnetic field at the end as well as at the center.

[0007]

In order to achieve the above object, the present invention has a permanent magnet or an electromagnet installed below a target and has a magnetic permeability of 1 at the center and the end of the target.
In a magnetron sputtering apparatus having a target cathode in which a magnetic substance of 00 or more is further installed, the magnets of the center and the edge portion are magnetic poles opposite to each other, and the center magnet and the edge magnet are joined with the magnetic substance sandwiched therebetween. Is characterized by.

[0008]

Next, the principle of the present invention will be described with reference to the drawings. As shown in FIG. 1, in the cathode structure of the magnetron sputtering apparatus of the present invention, the magnetic body 12 is provided above the magnetic poles of the permanent magnets 4 and 5 (the permanent magnet 4 is called an edge magnet and the permanent magnet 5 is called a center magnet). The magnetic materials 13 and 14 are installed above these magnetic materials.
And a target is installed between the magnetic bodies 13 and 14 (not shown), and the magnetic body 10 magnetically connects the permanent magnets 4 and 5. The edge magnet 4 and the center magnet 5 are directly connected to each other at the end portion in the longitudinal direction of the target. The magnetic body 12 is also installed above the edge magnet 4 and the center magnet 5 also in this connection portion. In the structure in which the center magnet 5 is short and the edge magnet 4 surrounds the periphery like the conventional example,
Although it is possible to connect the erosion regions in an elliptical shape, there is a limit to widen the erosion region at the end. The magnetic substance must have a magnetic permeability of 100 or more, and if it is less than 100, the leakage magnetic flux density at the end of the target becomes large, which is a problem. However, the present invention was developed so that the two erosions are stopped to be linked and the magnetic field at the central portion is directly realized at the end portion. As a result, the uniform part of the magnetic field could be greatly expanded even at the end. In the present invention, even if the above-mentioned permanent magnet is an electromagnet, the same effect can be expected. The edge magnet 4 and the center magnet 5 may be either N or S as long as the magnetic poles are opposite to each other.

[0009]

EXAMPLE The result of measuring the horizontal component of the magnetic field in the magnetron sputtering apparatus shown in FIG. 1 will be described below. Iron having a magnetic permeability of 500 was used as the magnetic material. Targets 1-1 ', 2-2', 3-3 ', 4-4' shown in FIG.
The horizontal component of the magnetic field (direction component of the line segment) along each line is shown in FIG. Comparing the distribution of the magnetic field at the center of 1-1 'and the distribution of the magnetic field at the end of 4-4' in FIG. 3, there was only a difference of about 10% in the maximum value. Figure 3
The maximum value of the horizontal component of the magnetic field at 1-1 'was 1140 G, and the maximum value at 4-4' was 1030 G. Moreover, the directions of the magnetic fields in the central portion and the end portions are the same. Further, the uniformity in each part was maintained in the area of 80% of the target.

Comparative Example A magnetic material 13 shown in FIG. 4 is a target cathode shorter than the magnetic material 11, and the targets 1-1 ', 2-2',
FIG. 3 shows horizontal components (direction components of line segments) of the magnetic field along the lines 3-3 'and 4-4'. Magnetic field distribution in the central part (1-1 ') and magnetic field distribution in the end part (4-)
Compared with 4 '), the value is different by 80% or more, and the uniformity is not maintained at the end portion. The maximum value of the horizontal component of the magnetic field at this time is (1-1 '), which is 1120G,
It was 200G at (4-4 ').

[0011]

As described in detail above, the present invention is
Since the horizontal component of the magnetic field is made uniform even at the end of the target, the entire target can be consumed without waste, and an expensive target can be effectively used.

[Brief description of drawings]

FIG. 1 shows a sketch of a target cathode of the present invention.

FIG. 2 is a diagram showing a horizontal component measuring portion of a target.

FIG. 3 is a diagram showing a relationship between a distance from a center of a target and a horizontal magnetic field component.

FIG. 4 shows a sketch of a conventional target cathode.

FIG. 5 shows a cross-sectional view of a conventional target cathode.

FIG. 6 is a diagram showing an erosion state of a conventional target cathode.

FIG. 7 is a diagram showing the principle of a conventional sputtering apparatus.

[Explanation of symbols]

 4 Edge magnet 5 Center magnet 10 Magnetic substance 12 Magnetic substance 13 Magnetic substance 14 Magnetic substance

Claims (1)

[Claims] 1. A permanent magnet or an electromagnet is installed below the target, and the magnetic permeability is 10 at the center and the end of the target.
In a magnetron sputtering apparatus having a target cathode in which 0 or more magnetic bodies are further installed, the center magnet and the edge magnet have opposite magnetic poles, and the center magnet and the edge magnet are directly joined. Magnetron sputtering equipment.