JPH0448871B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an improvement in a sputtering method using a ferromagnetic material such as Fe, Ni or an alloy thereof as a target.

Prior Art Generally, a parallel plate type is applied to the magnetron sputtering method. In addition, in this parallel plate type, when a ferromagnetic material is targeted, the magnetic field from the magnetic material is the ferromagnetic material (hereinafter referred to as
It's called a "target." ) It is also known that it is not possible to sufficiently confine plasma because the magnetic field does not come out to the surface side by passing through the inside of the plasma.

Therefore, in the past, the thickness of the target was made thin or a gap was provided in the target (Japanese Unexamined Patent Application Publication No. 1983-1999).
160113, 58-177468), it has been proposed to leak the magnetic field of the magnet body to the outside and allow it to pass through. In addition, by arranging arc-shaped magnets so as to face each other laterally near the surface of the target, and arranging the target separately at different heights between the N and S poles of the magnet, the target surface can be It is also known to generate a magnetic field parallel to (Japanese Patent Application Laid-Open No. 130277/1983).

Problems to be Solved by the Invention However, when the target is made thin, a magnetic field higher than the magnetic saturation point is applied, which causes rapid wear and tear on the target and extremely shortens its life. Further, when a gap is provided in the target, not only is the processing time-consuming, but the efficiency of forming a thin film on the workpiece is poor because spatter particles enter and adhere to the gap. In addition, when arc-shaped magnets are placed sideways facing each other near the surface of the target, the magnetic field generated by the magnets is generated parallel to the target surface, but the relative distance between the two ends is relatively small. This makes it impossible to distribute a uniform magnetic field over the entire width of the target, and
Since the target is separate from the N and S poles of the magnet and placed at different heights, the ferromagnetic target is magnetized by the magnetic field generated by the arc-shaped magnet, generating an external magnetic field, and the magnetic field causes the arc-shaped magnet to magnetize. Since the parallelism and uniformity of the magnetic field generated by the magnetic field are affected, it is inevitable that the sputtering efficiency will be reduced.

Means for Solving the Problems In the method for sputtering a ferromagnetic material according to the present invention, the N and S poles are located opposite to each other, and the longitudinal direction is straight and the cross section is approximately U-shaped with an interval between the poles. A ferromagnetic target forming a part of the magnetic circuit is interposed between the N and S poles on one side of each magnet body, and a ferromagnetic target forming a part of the magnetic circuit is sandwiched between the magnet bodies. N on the other side of
A magnetic field parallel to the surface of the ferromagnetic material is uniformly distributed between the S poles over the entire longitudinal width of each magnet,
This parallel magnetic field traps plasma and performs sputtering.

Function: In this sputtering method, a magnet body having a linear longitudinal direction and a substantially U-shape is placed on the surface side of a ferromagnetic target, with the N and S poles on one side facing each other. Plasma can be captured by distributing a uniform and parallel magnetic field over the entire length of the magnet, and a ferromagnetic target is sandwiched between the other N and S poles of the magnet and placed integrally. Since the target forms part of the magnetic circuit, the magnetic field of the ferromagnetic target does not affect the magnetic field of the magnet, and plasma can be captured efficiently, increasing sputtering efficiency and making thin films faster. be able to generate.

Embodiments The following description will be made with reference to the accompanying drawings.

This sputtering method can be carried out by applying the magnetic field generating device shown in FIG. The magnetic field generator applies a voltage of several hundred volts between an anode and a cathode to generate a glow discharge, causing ions to collide with a target and scattering spatter particles that are deposited on the surface of the workpiece substrate. as much as possible
It is placed in a vacuum atmosphere such as argon gas of 0.1 to 10 Pa. This magnetic field generating device includes magnet bodies 10, 11, 12, 13... (however, only the left and right sides in the drawing are shown with reference numerals) each having a linear longitudinal direction and a substantially U-shaped cross section. 10, 11, 12, and 13 are arranged by locating N and S poles opposite each other and leaving a space between each pole. Also, N and S poles on one side are 10
The ferromagnetic materials 14, 15, . Fe, Ni, or an alloy thereof can be used as the targets 14 and 15, and since these are ferromagnetic materials, they form part of the magnetic circuit of each magnet body 10, 11, 12, and 13. . In addition, these magnet bodies 10, 11, 12, 13 generate a continuous magnetic field between the other S and N poles 10b, 11b, 12b, 13b from a magnetic circuit formed by partially incorporating targets 14, 15. As a result, a magnetic field parallel to the targets 14 and 15 is formed. The magnetic field is applied to each magnet body 10, 11, 1
Since the targets 2 and 13 are formed on a straight line in the longitudinal direction, the plasma can be efficiently captured and the plasma density can be improved by uniformly distributing the plasma across the entire width of the targets 14 and 15.

In addition, the above-mentioned magnet bodies 10, 11, 1
2, 13... can be arranged linearly facing each other on both the left and right sides as well as the front and rear sides, and these can be assembled so that the magnet bodies facing each other as a whole have a rectangular shape (see the back side of the drawing in Figure 1). . Furthermore, each magnet body 10, 11, 12, 13 and targets 14, 15 are made up of packing plates 16, 17 made of magnetic material, and an insulating plate 18 laminated below the packing plates 16, 17.
It is placed on the plate surface of the base 20 via 19. From this base 20 to the packing plate 16,
Pipes 21 and 22 that supply cooling water through 17
The packing plates 16 and 17 can be cooled by piping. Further, shield plates 23 and 24 are arranged between and around each magnet body 10, 11, 12, 13, and the shield plate 2
Spatter particles can be scattered from the openings 3 and 24.

In this magnetic field generating device, as shown in FIG.
11, 12, 13, and in the magnetic circuit, a magnetic field parallel to the targets 14, 15 is generated at each pole 10b, 11b, 12b, 13b on the other side of the magnet body 10, 11, 12, 13. arise.
This parallel magnetic field is applied to the ferromagnetic targets 14, 15.
is the other pole 1 of the magnet body 10, 11, 12, 13
0a, 11a, 12a, and 13a to form a series of magnetic circuits, the target 14,
15, and since the longitudinal directions of the magnet bodies 10, 11, 12, and 13 are arranged to face each other on a straight line, plasma can be efficiently captured over the entire length. Therefore, when a voltage is applied to the targets 14 and 15 in a vacuum atmosphere, high-density plasma is focused around the targets, and the target surface can be bombarded with high ion density. Therefore, target 14,
15 is sputtered at high speed and a magnetic circuit attached to the target distributes a parallel and uniform magnetic field over the entire width of the target to capture the plasma, which improves sputtering efficiency by more than 20% compared to conventional methods. This makes it possible to efficiently sputter ferromagnetic materials.

Effects of the Invention As described above, according to the method for high-speed sputtering of ferromagnetic material according to the present invention, the target shape can be simply formed thickly, and there is no need to use a magnet with strong magnetism. Since the target is placed integrally between the N and S poles on one side of the magnet body to form a series of magnetic circuits, the magnetic field generated between the N and S poles on the other side of the magnet body is not affected by the ferromagnetic material. In addition, since the magnetic field is uniformly distributed across the entire width and parallel to the target between the N and S poles on the other side, which face each other linearly, sputtering can be performed continuously and efficiently at high speed. This is what makes it possible.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the configuration of a magnetism generating device used in the sputtering method according to the present invention, and FIG. 2 is an explanatory diagram of the operation of the same device. 10, 11, 12, 13...: Magnetic body, 1
0a, 11a, 12a, 13a: N, S on one side
Poles, 10b, 11b, 12b, 13b: N and S poles on the other side, 14, 15...: ferromagnetic material.

Claims (1)

[Claims] 1 N and S poles are located opposite each other, and magnetic bodies with a straight longitudinal direction and a substantially U-shaped cross section are provided facing each other with an interval between the poles, and the N and S poles on one side of each magnet body are A ferromagnetic target forming a part of the magnetic circuit is sandwiched between the S poles, and a magnetic field parallel to the surface of the ferromagnetic material is placed between the N and S poles on the other side of each magnet body. A method for high-speed sputtering of a ferromagnetic material, characterized in that sputtering is performed by uniformly distributing the plasma over the entire width in the longitudinal direction of each magnet body, and trapping plasma using the parallel magnetic field.