JPH04147971A - Through-type magnetron sputtering system - Google Patents

Abstract

PURPOSE:To uniformize the thickness of a thin film on a substrate by partly shielding the sputtered particles between a target and a substrate with a shielding plate. CONSTITUTION:The magnetron cathode consists essentially of an inner magnetic pole 1, an outer magnetic pole 2 and a target. Sputtered particle shielding plates 40 and 50 are arranged above the upper peripheral part of the outer magnetic pole 2 and above the inner magnetic pole 1. Since the amt. of the sputtered particles reaching a substrate 30 is affected by the shielding plate 50 when the erosion region is shifted inward, the sputtering rate is not apparently increased, and the film thickness distribution is improved in the longitudinal direction of a magnetron. This through-type magnetron sputtering system is effective for either nonmagnetic or ferromagnetic target.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a through-type magnetron sputtering device.

[Conventional technology]

A conventional through-type magnetron sputtering device will be explained with reference to FIGS. 3 to 6.

Fig. 3 is a conceptual diagram of a through-type magnetron sputtering device, Fig. 4 is an explanatory diagram of a magnetron cathode, Fig. 5 is an explanatory diagram of a storage container for a magnetron cathode, and Fig. 6 is a conceptual diagram of a through-type magnetron sputtering device. It is a partial cross-sectional explanatory view.

As shown in Figure 3, the through-type magnetron sputtering device has a magnetron cathode (
A plurality of magnetron cathodes (20) are arranged.
A substrate (30) is arranged horizontally movably on the top of the device. The magnetron cathode (20) usually has different types of targets according to their number and is arranged in a continuous manner in order to form a multilayer thin film on the substrate (30).

As shown in FIG. 4, the magnetron cathode (20) has an inner magnetic pole (1), an outer magnetic pole (2) that is arranged surrounding the inner magnetic pole (1), and has an opposite polarity to the inner magnetic pole. , mainly composed of target materials (3) placed on both magnetic poles near the inner magnetic pole to the outer magnetic pole. The bottoms of the inner magnetic pole (1) and the outer magnetic pole (2) are usually
They are connected by a magnetic yoke (4) made of a soft magnetic material such as soft rope. In addition, (5) in FIG. 4 is a backing plate.

In the through-type magnetron sputtering apparatus as described above, a voltage is applied between the target material (3) and the substrate (30), and a thin film is formed on the surface of the substrate while moving the substrate.

That is, in use, the inside of the vacuum chamber (lO) is set to a low pressure Ar atmosphere, and the target material (3) and the substrate (30) are
A voltage is applied between them, and the Ar gas is ionized by the electrons emitted from the surface of the target material (3). By colliding the Ar ions with the target material (3), the target material is knocked out and the substrate ( 30) Generate a thin film on the surface of The substrate (30) is made of target material (
3), and film formation is performed continuously.

The leakage magnetic field created by both magnetic poles efficiently captures the electrons, promotes ionization of Ar, and improves sputtering efficiency.

And the magnetron cathode (20) is generally
A magnetron cathode storage container as shown in Figure 5 (
As shown in FIGS. 5 and 6, the upper peripheral edge of the storage container (60) is both inclined inward, and the inclined portion allows the outer magnetic pole (2 ) functions as a sputter particle shield (40). The sputtered particle shield (40) effectively prevents contamination between the magnetron cathodes (20) due to sputtered particles.

[Problem to be solved by the invention]

By the way, the appearance of the two lotions on the surface of the target material (3) depends on the magnetic field distribution, is usually localized as shown in FIG. 11, and changes depending on the disturbance of the magnetic field distribution.

FIGS. 7(a) and 7(b) schematically show changes in the flight of sputtered particles reaching the substrate (30) when the position of the two lotions changes in the conventional apparatus.

FIG. 7(b) shows a case where the two lotion regions are biased to the outside compared to FIG. 7(a), and in this case, the substrate (30
) is reduced under the influence of the shielding plate (40), resulting in an apparent slowing of the sputtering speed. In other words, in the conventional apparatus, the film forming speed apparently decreases as the two lotions shift toward the outside.

Therefore, in the conventional apparatus, if there is a partial deviation in the two lotion regions in the longitudinal direction as described above, there is a problem in that a film thickness distribution occurs in the longitudinal direction as described below.

FIG. 9 is an explanatory diagram of the longitudinal film thickness distribution of the magnetron cathode (20) at the position of the substrate (30) in the conventional device. FIG. 11 is an explanatory diagram of the erosion distribution of the target material in this case. 9th
As is clear from the figure, the erosion region is slightly biased toward the inner magnetic pole at the longitudinal center portion, and slightly biased toward the outer magnetic pole at portions near both longitudinal ends. In the film thickness distribution shown in Fig. 9, the film thickness is thick at the longitudinal center and becomes thinner toward both ends because of the geometry of the two lotions and the shielding plate (40) shown in Fig. 11. It can be understood from the positional relationship. Furthermore, the film thickness increases again near both longitudinal ends, but this is thought to be due to the two lotion regions on the short sides.

The present invention has been made to solve the above-mentioned drawbacks, and its purpose is to improve the film thickness distribution on the substrate so that it can be reduced even when the erosion region is biased due to variations in the magnetic field distribution. The purpose of the present invention is to provide a through-type magnetron sputtering device.

[Means to solve the problem]

The above object of the present invention is to arrange a plurality of magnetron cathodes (20) in a vacuum chamber (10), and the magnetron cathodes are arranged to surround an inner magnetic pole (1) and an inner magnetic pole (1); It mainly consists of an outer magnetic pole (2) having a polarity opposite to that of the inner magnetic pole, a target material (3) placed on both magnetic poles near the inner magnetic pole and the outer magnetic pole, and a substrate on the top of the magnetron cathode (20). (30
) are arranged so as to be movable in the horizontal direction, and a voltage is applied between the target material (3) and the substrate (30),
In a through-type magnetron sputtering device that forms a thin film on the surface of the substrate while moving the substrate, a sputtered particle shielding plate (40) is provided on the upper peripheral edge of the outer magnetic pole (2) and the upper part of the inner magnetic pole (1); (50) is arranged to partially block sputtered particles between the target material (3) and the substrate (30).

[Effect]

Sputter particle shielding plates (40) and (50) partially block sputter particles between the target material (3) and the substrate (30). As a result, even if the sputtering area is biased toward the center of the target material, the shielding plate (50) located at the top of the inner magnetic pole controls a large amount of sputtered particles from reaching the substrate (30). Good thickness distribution of the thin film is maintained.

〔Example〕

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist thereof.

FIG. 1 is an explanatory diagram showing an example of a storage container for a magnetron cathode used in the present invention, and FIG. 2 is a partially sectional explanatory diagram showing an example of a through-type magnetron sputtering apparatus of the present invention.

The through-type magnetron sputtering device of the present invention includes:
It is configured by arranging a plurality of magnetron cathodes (20) in a vacuum chamber (10), and the magnetron cathodes (20) are arranged surrounding an inner magnetic pole (1) and an inner magnetic pole (1), and are opposite to the inner magnetic pole. outer magnetic pole (2) with polarity of
, is the same as the conventional apparatus shown in FIGS. 3 and 4 in that it is mainly composed of a target material (3) placed on both magnetic poles near the inner magnetic pole to the outer magnetic pole.

In the present invention, a sputtered particle shielding plate (40), (
50).

The method of arranging the sputtered particle shielding plates (40) and (50) is not particularly limited, but the sputtered particle shielding plates (40)
As with conventional devices, it is convenient to use a magnetron cathode storage container whose upper peripheral edge is inclined inward. When such a magnetron cathode storage container is used, the sputtered particle shielding plate (50) can be constructed using the storage container.

FIG. 1 is an explanatory diagram of a magnetron cathode storage container (60) constructed as described above and provided with sputtered particle shielding plates (40) and (50).

As in the conventional case, the magnetron cathode storage container (60) has its upper peripheral edge inclined inward to form a sputter particle shielding plate (40), and also has a plate-shaped body approximately in the center thereof. Sputter particle shielding plate (
50).

The width of the plate-shaped body constituting the sputtered particle shielding plate (50) can be determined as appropriate, but is usually 10 to 30% of the width of the target material (3). Further, its material is usually the same as that of the magnetron cathode storage container, such as non-magnetic material such as aluminum alloy or stainless steel.

The height of the sputtered particle shielding plate (50) is determined by the distance L between the surface of the target material (3) and the surface of the substrate (30).
When L2 is the distance between the surface of the target material (3) and the surface of the sputtered particle shielding plate (50), L2/
L is in the range of 0.1 to 0.6 (value based on the surface of target material (3)), preferably 0.15 to 0.4.

Note that the height of the sputtered particle shielding plate (40) is not particularly limited, but usually, the height of the sputtered particle shielding plate (50) is
It is best to set it at the same height.

FIGS. 8(a) and 8(b) schematically show changes in the flight of sputtered particles reaching the substrate (30) when the position of the two lotions changes in the apparatus of the present invention.

FIG. 8(a) shows a case where the second lotion area is biased inward compared to FIG. 8(b); in this case, the substrate (3)
The amount of sputtered particles reaching 0) is determined by the amount of sputtered particles reaching the shielding plate (50)
Because of the influence of can do.

FIG. 1O shows the film thickness distribution in the longitudinal direction of the magnetron at the substrate position in the apparatus of the present invention.

As is clear from FIG. 3, it can be seen that the film thickness is almost constant except that it becomes thicker at both ends in the longitudinal direction.

The device of the present invention is effective for both non-magnetic and ferromagnetic target materials, but in particular, the magnetic field distribution changes as the two lotions progress, and the erosion area tends to change depending on the location. Effective against ferromagnetic targets.

〔Effect of the invention〕

According to the bay invention described above, even if the sputtering area is biased toward the center of the target material, the shielding plate located at the top of the inner magnetic pole can control a large amount of sputtered particles from reaching the substrate. Good thickness distribution of the thin film can be maintained.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an example of a storage container for a magnetron cathode used in the present invention, and FIG. 2 is a partially sectional explanatory diagram showing an example of a through-type magnetron sputtering apparatus of the present invention. 3 to 6 are explanatory diagrams of a conventional through-type magnetron sputtering device, FIG. 3 is a conceptual diagram of a through-type magnetron sputtering device, FIG. 4 is an explanatory diagram of a magnetron cathode, and FIG. 6 is an explanatory view of a storage container for a magnetron cathode, and FIG. 6 is an explanatory partial cross-sectional view of a through-type magnetron sputtering device. FIGS. 7(a) and 7(b) schematically show changes in the flight of sputtered particles in a conventional apparatus. FIGS. 8(a) and 8(b) schematically show changes in the flight of sputtered particles in the apparatus of the present invention. FIG. 9 is an explanatory diagram of the film thickness distribution in the conventional device,
The θ diagram is an explanatory diagram of the film thickness distribution in the apparatus of the present invention. FIG. 11 is an explanatory diagram of two lotion patterns in a conventional device. In the figure, (1) is the inner magnetic pole, (2) is the outer magnetic pole, (3) is the target material, (10) is the vacuum chamber, (20) is the magnetron cathode, (30) is the substrate, (40) is the sputter A particle shielding plate is shown.

Claims (1)

[Claims] (1) Magnetron cathode (20) in vacuum chamber (10)
a plurality of magnetron cathodes are arranged, the magnetron cathode is arranged surrounding an inner magnetic pole (1), and the inner magnetic pole (1);
It mainly consists of an outer magnetic pole (2) having a polarity opposite to the inner magnetic pole, and a target material (3) placed on both magnetic poles near the inner magnetic pole and the outer magnetic pole. A substrate (30) is arranged so as to be movable in the horizontal direction, and a voltage is applied between the target material (3) and the substrate (30) to form a thin film on the surface of the substrate while moving the substrate. In a through-type magnetron sputtering device designed as such, the outer magnetic pole (2)
Sputter particle shielding plates (40) and (50) are placed around the upper edge of the target material (3) and above the inner magnetic pole (1).
A through-type magnetron sputtering device characterized in that sputtered particles are partially blocked between the substrate (30) and the substrate (30).