JPS62119907A - Sputtering device for formation of magnetic thin film - Google Patents

Abstract

PURPOSE:To enable the uniform magnetic characteristics of a magnetic film by forming the magnetic film of which the film ratio of inclined planes and flat parts is 0.75 or more on a substrate having a plurality of high step parts and flat parts by determining the angle made by the substrate surface with the line connecting an erosion area of a target and the edge of the substrate which is nearest to said area 55 deg. or under. CONSTITUTION:An upper magnetic film 5 is formed on the magnetic core for a thin film magnetic head in which a lower magnetic member 2, a conductive coil 3, and an insulator 4 are arranged on a substrate 1. At the same time, a magnetic film 5 is formed on the substrate on which hundreds of such elements are formed. A magnetron magnet 7 is put under a target 6 and the substrate 1 is arranged oppositely to an erosion area 8 of the target. The angle thetamade by the substrate surface with the line connecting said erosion area 8 and the edge of the substrate 1 which is nearest the area 8 is determined as theta<=55, thereby obtaining the magnetic film 5 whose step coverage b/a is at least 0.75 on the substrate 1 having a plurality of high step parts and flat parts.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a magnetron type sputtering apparatus, and in particular to a magnetic thin film production coating suitable for simultaneously forming a magnetic film with a uniform thickness on a large number of substrates with stepped portions. This invention relates to a sputtering device.

゛ [Background of the Invention] In order to obtain a uniform film thickness distribution in this type of device, conventionally the size of the target has been made to be more than twice the size of the substrate, or the distance between the target and the substrate has been increased.

For this reason, it is difficult to miniaturize the device and the efficiency of sputtering is poor. However, even with this method, the thickness distribution of the film formed on the substrate is not always satisfactory. As a way to improve this, Unexamined Japanese Patent Publication No. 57
As described in No. 192262 and Japanese Unexamined Patent Publication No. 57-76185, methods are known in which a plurality of targets are used and each target is arranged in a bowl shape, or in a V-shape6. However, such a method requires a plurality of target electrode sections, making the apparatus complicated and expensive. Furthermore, even with this method, it is difficult to maintain a film thickness ratio of 0.75 or more between the flat portion and the sloped portion, for example, when the substrate has many sloped portions with high steps. . Furthermore, since there is no mention of the incident angle of sputtered atoms onto the substrate and no consideration is given to the placement of the substrate, it is extremely difficult to form a uniform film thickness over a relatively large area.

[Purpose of the invention]

An object of the present invention is to provide a sputtering apparatus that can simultaneously form a thin film of uniform thickness on at least two substrates with a comparative angle surface, and also on substrates having many high-level sloped portions and flat portions. There is something to do.

[Summary of the invention]

When forming a magnetic film on a substrate with flat and sloped parts,
In order to obtain good magnetic properties, it is necessary to make the ratio of the film thickness of the flat part to the slope part 0.75 or more.

FIG. 1 shows the pattern and cross section of a magnetic core for a step type thin film magnetic head. A lower magnetic body 2, a conductor coil 3, and an insulating material 4 are provided on a substrate 1. In this state, the film of the upper magnetic body 5 is formed. Therefore, the magnetic film is formed on the flat portion and the sloped portion at the same time.

Note that normally, several hundred such elements are formed on a 3-inch φ substrate, for example. In magnetic recording, since the magnetization of the sloped part is easily saturated, the ratio of the film thickness a of the flat part to the film thickness of the sloped part, that is, the step coverage b/a, is ideally 1.
, it is desirable for practical use to be 0.75 or more.

With conventional magnetron sputtering equipment, as mentioned above, a substrate with such a stepped portion can be sputtered.

It has been difficult to form films with high step coverage. Therefore, we investigated a method for obtaining a film with high step coverage and found that the positional relationship between the erosion area of the target and the substrate should be arranged as shown in the present invention.

[Embodiments of the Invention] One embodiment of the present invention will be described below. FIG. 2 shows the positional relationship between the erosion area of the target of the present invention and the substrate. The magnetron magnet 7 is installed under the target 6, and is usually submerged in water for target cooling. The substrate 1 is placed opposite to the target erosion area 1.
is located. Although not shown, at least one of the substrate and the cathode portion including the target and magnetron magnet has a structure that allows the distance LIII between the substrate and the target to be changed.

[Example 1] In FIG. 2, a disk target with a diameter of 10 inches was used, and the distance between the substrate and the target was 75 m.

When the center position of the erosion area of the target is 68 cm from the center of the target, when a film is formed on a step part as shown in Figure 1 by RF magnetron sputtering method on a 3-inch substrate, the step coverage b/a is 0.
．． 7, the sputtering conditions were -Ar gas pressure 5
X 10-'Torr, output 2KW, board temperature 250
'C. At this time, θ in Figure 2 is 77.25''. When the distance between the substrate and the target was changed in Figure 2 and the relationship between the angle θ and the step coverage b/a was investigated, the relationship in Figure 4 was found. The results were obtained. From Figure 3, the range where step coverage b/a≧0.75 is 0≦5.
5".

[Example 2] As shown in Fig. 3, using a 5' x 15' rectangular target and changing the distance between the target and the 3'φ substrate, the angle Ox and step coverage b were determined as in Example 1. As a result of experimenting with the relationship /a, results similar to the fourth example were obtained. That is, when b/a≧0.75, it is 08555 degrees.

Note that in this case, it is a rectangular target.

(ly<08. Also, the same results as in Fig. 4 are obtained in the case of a square target. In this case, 0
8=θy≦55 degrees.

[Example 3] In Examples 1 and 2, the substrate was one 3#φ substrate, but next, a 10' x 20' rectangular target was used as a substrate as shown in Fig. 5. When three 3'φ substrates were arranged and an experiment was conducted on the relationship between OX, θ and b/a, the condition for b/a≦0.75 was θy〈θX≦55°, as in Example 2. I understand.

As described above, the embodiments of the present invention have the advantage that a film with high step coverage can be formed in the high step portion.

In the embodiments described above, the distance between the erosion area of the target and the substrate was changed so that the optimum angle of 0 was obtained. Conversely, the target and the substrate may be fixed, and the erosion area of the target may be moved to obtain the optimal angle θ. In this case, the position of the magnetron magnet provided under the target may be adjusted as shown in Figure 6. This is made possible by adopting a structure of the target electrode section that can vary the . At this time, if a permanent magnet is used as the magnetron magnet, the magnetic target and the magnetron magnet are attracted to each other by a strong attractive force, so it is difficult to easily move the magnet.

Therefore, it is desirable to arrange a rolling ball 9 between the magnetron magnet and the target to facilitate the movement of the magnet.

〔Effect of the invention〕

According to the present invention, a magnetic film having a uniform film thickness, that is, a film thickness ratio of the slope portion to the flat portion is 0.75 or more, is formed on a substrate having many slope portions with high steps and flat portions. This has the effect of making the magnetic properties of the magnetic film on the sloped portion and the flat portion uniform.

[Brief explanation of drawings]

FIG. 1 shows the pattern of a step-type magnetic head core of an embodiment of the sputtering apparatus for producing a magnetic film of the present invention, in which (a) is a plan view, (b) is a cross-sectional view taken along line xx' of (a),
Figure 2 is a cross-sectional view showing the positional relationship between the circular target and the substrate, and Figure 3 is (a) for the same rectangular target.
is the short axis direction. (B) is a cross-sectional view in the long axis direction, FIG. 4 is an explanatory diagram showing the relationship between the angle θ and step coverage, FIG. (b) is a Y-Y' cross-sectional side view of (a), (c) is (
B) x-x' cross-sectional front view, No. 61! Similarly, I is an explanatory diagram when a ball is placed between the target and the magnetron magnet. 1... Board, 6... Target, 7... Magnetron magnet, 8... Erosion area.

Claims (1)

[Claims] 1. A target and a substrate holder arranged to face each other in a vacuum container, a power supply means for supplying power between the target and the substrate holder, and a power supply means for supplying power between the target and the substrate holder arranged in the vacuum container. magnetic field generating means for forming a magnetic field orthogonal to the electric field by the power supply means in a region near the target via the target, and generating a leakage magnetic flux in front of the target to generate an erosion region. In a sputtering apparatus that forms an alloy magnetic film on a substrate supported by the substrate holder so as to face the target, the sputtering device is the one closest to the erosion area in the positional relationship between the erosion area of the target and the substrate. A method for producing a magnetic thin film characterized in that the angle θ between the line connecting the periphery of the substrate and the erosion area and the substrate surface is θ≦55 degrees so that the film can be uniformly applied to multiple substrates. Sputtering equipment.