JPH01108375A - Magnetron sputtering device - Google Patents

Abstract

PURPOSE:To reduce the unused region of a target and to increase the film forming rate of the title device by forming a magnetic field generating magnetic circuit with a central magnet, an annular magnet, and an annular magnet having a magnetization direction parallel to the target surface from the center toward the outer periphery. CONSTITUTION:The central magnet 11 having a magnetization direction vertical to the target surface is arranged at the center of a magnetic circuit, and the annular magnet 12 having a magnetization direction reverse to that of the central magnet 11 is arranged on the outer periphery. Furthermore, the annular magnet 13 having a magnetization direction parallel to the target surface and extending from the outer periphery to the center is arranged to bridge the upper and lower parts of the central magnet 11 and the annular magnet 12. The ferromagnetic field region is increased by about 1.3-1.8 times as compared with the conventional device, hence the erosion region to be sputtered is increased, and the utilization efficiency of the target is improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a magnetron sputtering device that generates a large strong magnetic field region using a permanent magnet magnetic circuit built into a target support base and obtains a wide sputtering region. .

[Prior Art] As shown in FIG. 8, a magnetron sputtering apparatus includes a target support 5 containing a target 4 and a magnetic circuit in a vacuum vessel 1 equipped with a sputtering gas introduction pipe 2 and an exhaust device 3; In contrast, a substrate 6 on which a thin film is to be formed is held by a substrate holder 7.

In order to form a thin film on the surface of the substrate 6 using such a magnetron sputtering device, the inside of the vacuum chamber 1 is evacuated by the exhaust device 3, and then a sputter gas such as argon gas is introduced from the sputter gas introduction pipe 7. , target 4
Apply a predetermined voltage to. The sputtering gas plasma generated at this time is focused by a magnetic field generated by a magnetic circuit consisting of an annular magnet and a central magnet built into the target support 5, and collides with the target 4, thereby sputtering the sputtered material on the surface. [1] is produced on the substrate 6 at a high deposition rate.

[Problems to be Solved by the Invention] In the magnetron sputtering apparatus as described above, the component of the magnetic field generated by the magnet built in the target support is directed outward from the center of the target or from the outside to the inside, and is parallel to the target surface ( Since the gas plasma is focused and sputtered by B1),
Annular strong magnetic field on the target! The gas plasma gathers in the i region, and this region is locally sputtered to become an eroded annular erosion region, and the other regions are hardly sputtered.

Here, the strong magnetic field region refers to a region where BR exhibits a magnetic field strength of 80% or more of its maximum value on the target surface.

To explain this with the help of drawings, FIG. 9 shows an example of a magnet circuit built into the target support base 5, in which a central cylindrical magnet 9 and an annular magnet 10 are arranged on the back yoke 8, surrounding the central cylindrical magnet 9. . FIG. 10 is a graph showing the relationship between the position of this magnet circuit and the number 8. The strong magnetic field a region appearing here is shown in a plan view as shown in FIG. 11, and this region is 35% of the target surface area.

The aforementioned gas plasma gathers in this annular strong magnetic field region,
This becomes an annular erosion area.

FIG. 12 shows an example in which each magnet is rectangular, FIG. 13 is a distribution graph of eight magnets, and FIG. 14 is a plan view of the same ferromagnetic region, which is 32% of the target surface area.
``The life of a target is until the depth of this annular erosion area reaches the target support stand or target back plate, and a target that is no longer usable will have many unused parts remaining outside the erosion area.

Furthermore, since the region to be sputtered is limited to the erosion region, which is a strong magnetic field region, this also causes a reduction in the thin film production rate.

Therefore, in the present invention, the unused area of the target is small and
It is an object of the present invention to provide a magnetron sputtering device with a high film formation rate.

[Means for Solving the Problems] The present invention provides a magnetron sputtering apparatus comprising a target disposed in a vacuum container and a means for generating a magnetic field near the surface of the target, in which a magnetic circuit for generating the magnetic field comprises:
Central magnet, annular magnet, and 1161 from the center to the outer circumference or from the outer circumference to the center and parallel to the target surface.
This is a magnetron sputtering device characterized by being composed of an annular magnet having one direction.

In the above, the central magnet and each annular magnet may be formed into a square shape.

Compared to conventional magnetic circuits, such a magnetic circuit further disposes an annular magnet having a magnetization direction from the center to the outer periphery or from the outer periphery to the center and parallel to the target surface, so that the strong magnetic field region is aligned with the target. 40 of surface area
% or more of the magnetic circuit.

[Function] The present invention generates a wide strong magnetic field region using a magnetic circuit built into the target support, thereby reducing the unused region of the target and increasing the film formation rate.

[Example] Embodiments of the present invention will be described in detail below with reference to the drawings.

The main feature of the present invention lies in the configuration of the magnetic circuit within the target support, and the rest of the structure is the same as that shown in FIG. 8, so the explanation will be given only with respect to the magnetic circuit.

Note that the examples are representative examples and do not limit the scope of the present invention, and of course there are other examples within the scope of the present invention.

Example 1 This is a configuration diagram of the magnetic circuit for a round target in FIG. 1, and the arrow in the figure indicates the magnetization direction of the magnet.

A central magnet 11 having a magnetic direction perpendicular to the target surface is arranged at the center of the magnetic circuit, and an annular magnet 12 whose magnetic direction is opposite to that of the central magnet 11 is arranged at the outer circumference d.
Further, an annular magnet 13 is arranged so as to span over the center magnet 11 and the annular magnet 12, parallel to the surface of the target and having a magnetization direction from the outer periphery toward the center. Reference numeral 8 denotes a back yoke, which is placed on the lower surface of the magnetic circuit to prevent leakage magnetic fields. The magnet used in the magnetic circuit needs to have a sufficiently large coercive force.

The target surface is located 12 av above the upper surface of the magnetic circuit, and FIG. 2 shows the distribution of B1 and the strong magnetic field region on that surface, and FIG. 3 shows a plan view of the strong magnetic field region.

In this example, the strong magnetic field area accounts for 47% of the total target surface area.
It is. Further, in FIG. 4, the magnetic direction is different from that in FIG. 1, that is, the direction of magnetization of the annular magnet 13 is from the center to the outer circumferential direction.

Embodiment 2 FIG. 5 is a configuration diagram of a magnetic circuit for a square target, in which a square central magnet 14 having magnetization perpendicular to the target surface is arranged at the center position of the magnetic circuit, and square central magnets 14 are arranged at the outer circumferential position of the square central magnet 14. A square annular magnet 15 with the magnetization direction reversed is arranged,
Further, a square annular magnet 16 is arranged so as to span over the square central magnet 14 and the square annular magnet 15, parallel to the surface of the target and having a magnetization direction from the outer periphery toward the center.

8 is a back yoke.

Fig. 6 is a graph showing the distribution of B and L on line A-A'' in Fig. 5 and the strong magnetic field region, and Fig. 7 is a plan view of the strong magnetic field region. This is 42% of the total target surface area.

[Effects of the Invention] In the magnetron sputtering apparatus of the present invention, the strong magnetic field area on the target surface is approximately 1.3 to 1.8 times larger than that of conventional products, and the erosion area to be sputtered is correspondingly large. The unused portion of the film is reduced, the utilization efficiency is improved, and a higher deposition rate can be obtained. Therefore, excellent effects can be obtained when applied to the manufacture of semiconductor integrated circuits and magnetic recording media. Further, since the magnetic circuit according to the present invention generates a strong magnetic field over a wide area, the structure of the magnetic circuit itself can be applied to, for example, a magnetic circuit for magnetic levitation MRI.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a magnetic circuit according to an embodiment of the present invention, FIG. 2 is a distribution graph of B, and FIG. 3 is a plan view of the strong magnetic field region.
Fig. 4 is a block diagram of a modification of Fig. 1, Fig. 5 is a block diagram of a magnetic circuit of another embodiment, Fig. 6 is a distribution graph of 8N, and Fig. 7 is a plan view of the strong magnetic field region. , Fig. 8 is a conceptual diagram of a magnetron sputtering device, Fig. 9 is a configuration diagram of a conventional magnetic circuit, Fig. 10 is a distribution graph of B1, Fig. 11 is a plan view of the strong magnetic field region, and Fig. 12 is a diagram of a conventional magnetic circuit. FIG. 13 is a diagram showing the configuration of another conventional magnetic circuit, and FIG. 13 is a distribution graph of B, and FIG. 14 is a plan view of the strong magnetic field region.

Claims (1)

[Scope of Claims] (1) In a magnetron sputtering apparatus comprising a target disposed in a vacuum container and means for generating a magnetic field near the surface of the target, a magnetic circuit for generating a magnetic field includes a central magnet, an annular magnet and a central magnet. 1. A magnetron sputtering apparatus comprising an annular magnet having a magnetization direction parallel to a target surface, either from the outer periphery or from the outer periphery to the center. (2) The magnetron sputtering apparatus according to claim (1), wherein each magnet has a rectangular shape. (3) Claim (1) or (2) in which the strong magnetic field region has a magnetic circuit that is 40% or more of the target surface area.
) The magnetron sputtering device described in item 2.