JPS62232911A - Magnetic film forming device - Google Patents

Abstract

PURPOSE:To form a magnetic thin film superior in magnetic characteristics on a substrate by means of a miniaturized device, by installing an auxiliary magnetic field generating device which generates the magnetic field nearly parallel to the one generated by a main magnetic field generating device in a magnetic film forming device. CONSTITUTION:A magnetic film forming device is composed of a target 10, a substrate 6, a substrate holder 3 holding the substrate 6, a main magnetic field generating device 1 which impresses the magnetic field on the substrate 6plane, and a vacuum container 7 housing their parts. And, an auxiliary magnetic field generating device 14 which generates the magnetic field nearly parallel to that generated by the device 1 is installed. Then, a magnetic field, which is uniform and parallel to the substrate 6 plane, is generated over a wide range on the holder 3. Hence, a magnetic thin film superior in magnetic characteristics is formed on the substrate 6 by means of this miniaturized device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic film forming apparatus, and more particularly to a magnetic film forming apparatus for forming a magnetic film on a substrate by sputtering.

[Conventional technology]

2. Description of the Related Art Thin-film magnetic heads, in which a thin magnetic film is formed, are widely used as magnetic heads used in magnetic recording and reproducing devices. Many methods have been developed and put into practical use for producing thin film magnetic heads, including sputtering, vacuum evaporation, magnetron, and facing target methods, but they offer good reproducibility of thin films and strong adhesion to the substrate. The sputtering method is often used because of the following advantages. There are many types of thin films ranging from metal films to insulating films, but the thin films used in magnetic heads and the like are often made of magnetic materials.

When a thin film of a magnetic material is formed on a substrate by sputtering, it is necessary to apply a parallel magnetic field during film formation and perform sputtering while aligning the magnetic domains in a certain direction in order to obtain magnetic properties. For this reason, the current state of the art is "High Density Magnetic Recording Technology Collection" (Supervised by Tsushima Tatebe).

Published by Sogo Technological Center) Figure 1.2, pages 167 and 197
As described above, a method is employed in which a magnetic field is generated and applied using a magnetic field coil or a permanent magnet in the direction in which the magnetic domains are desired to be aligned.

[Problem that the invention seeks to solve]

However, in this method, when an external magnetic field is applied by the magnetic field coil 1 as shown in FIG. Must not be. For this reason, as shown in FIG. 4(b), magnetic pole plates 4 made of magnetic material are provided on both sides of the substrate holder 3, and by concentrating the magnetic flux on the magnetic pole plates 4, the spatial magnetic field on the substrate is made more uniform and parallel. method is known. According to this method, the uniformity of the magnetic field on the substrate is improved, but as is clear from FIG. 1, the lines of magnetic force 2 are not straight lines but arcuate, so it is not possible to make the lines of magnetic force 2 parallel over the entire area of the substrate.

Especially recently, as multiple substrates are often processed at the same time to improve productivity, the distance between the magnetic pole plates 4 has increased, making it increasingly difficult to apply a parallel and uniform magnetic field over the entire area of multiple substrates. It is becoming. For this reason, the fourth
As shown in Figure (C), a plurality of magnetic pole plates 5 are connected to
It is considered that the magnetic field applied to the substrate 6 is made parallel and uniform by providing the magnetic field between the substrates 6 and 6. However, even with this method, it is still not possible to make the magnetic lines of force 2 parallel over the entire area of the substrate 6, and in this method, the length of the substrate holder 3 becomes longer by the width of the added magnetic pole plate 2, resulting in a larger device. There were also problems.

The present invention has been made in view of the above-mentioned circumstances, and is a compact magnetic film formation method that can generate a uniform magnetic field parallel to the substrate surface over a wide range and can form a magnetic thin film with excellent magnetic properties. i&Ql! The purpose is to provide t.

[Means for solving problems]

In order to achieve the above object, the present invention includes a target made of a film forming material, a substrate which is a base material to be film formed, a substrate holder that holds this substrate, and a main magnetic field that applies a magnetic field onto the surface of the substrate. In a magnetic film forming apparatus comprising a generating device and a vacuum container that houses and holds at least a part of the generating device,
An auxiliary magnetic field generating device is provided that generates a magnetic field substantially parallel to the magnetic field generated by the main magnetic field generating device.

[Effect]

According to the above configuration, the magnetic fields generated by the main magnetic field generating device and the auxiliary magnetic field generating device strengthen each other in the main magnetic field application direction on the substrate surface, and weaken each other in the direction perpendicular to this. , it is possible to increase the strength and uniformity of the magnetic field in the applied direction on the substrate surface.

〔Example〕

An embodiment of the magnetic film forming apparatus according to the present invention will be described below with reference to the drawings.

An embodiment of the present invention is shown in FIGS. 1, 2, and 3.

In these figures, parts that are the same or equivalent to those of the conventional example shown in FIG. 4 are denoted by the same reference numerals.

In the figure, the bottom of the vacuum container 7 has a cathode ttt4i.
A target holder 9 connected to 8 is provided,
Targeters 1 to 10 made of a magnetic material are placed on this target holder 9. The cathode 1if pole 8 is connected to the vacuum chamber f! 7 through an insulator 11 in an airtight manner. A pair of Helmholtz coils 1 are provided in the upper part of the vacuum chamber D7 as a main magnetic field generator.
A magnetic field is formed between them. At least one substrate 6 held by a substrate holder 3 is arranged between these coils 1, and a shutter 12 is provided between this substrate holder 3 and the target 10. Also, vacuum container 7
A substrate heater 13 is provided above the substrate holder 3 inside, and magnetic pole plates 4 made of permalloy or the like are integrally provided at both ends of the substrate holder 3. Also, the board holder 3
A pair of permanent magnets 14 are disposed on both sides of the substrate 6 at a certain distance from the substrate holder 3 on a plane parallel to the substrate 6 as an auxiliary magnetic field generating device. If a magnetic field is generated on the substrate holder 3 from left to right in the figure by the pair of coils 1, for example, this permanent magnet is arranged with its north pole facing left in the figure.

Next, the operation of this embodiment will be explained. Figure 3(a).

(b) shows the magnetic fields generated separately by the permanent magnet 14 and the coil 1. NKa of the permanent magnet 14 is formed on the left side of the figure, and indicates the direction of the current flowing in the same direction in the left and right pair of coils 1. In the coil cross section on the left and right sides of Figure 1, the direction from the back side to the front side of the paper is selected, so a magnetic field is generated in the direction of the magnetic lines of force 2 shown in the figure. To apply a uniform magnetic field to both ends of the substrate holder 3? jt
Although the polar plate 4 is arranged, the magnetic lines of force 2 due to only the coil 1 are not uniformly parallel except for a small part at the center, as shown in FIG. 3(b). However, as shown in FIG. 3 (Q), when a pair of permanent magnets 14 are placed facing each other between the coils 1, the magnetic forces Ai2 on the substrate holder 3 become almost parallel as shown in FIG. The magnetic field strength in the X direction in the figure increases.

This can be achieved for the following reasons. That is, if we compare the magnetic field at a certain point Ms on the magnetic force Jli2 shown in FIG. 3(a) with the magnetic field at point C1 on the magnetic field line 2 shown in FIG. 3(b) at a position aligned with this point Mt, The magnetic field B MIX in the X direction and the magnetic field B ctx in the X direction at point C1 are in the same direction, but their respective Z
The magnetic field BMI□ and )3ctz are opposite in direction. Therefore, when the two are combined, they strengthen each other in the X direction, but cancel each other out in the two directions. This also applies to other points Mz and C2 shown in FIGS. 3(a) and 3(b), respectively.

Therefore, in FIG. 3(c), the parallelism of the magnetic field in the X direction is improved and the strength is also increased by 1.

According to this embodiment, a parallel, uniform, strong magnetic field can be applied over the entire substrate holder 3 without requiring the intermediate magnetic pole plate provided in the conventional example. Furthermore, the substrate holder 3 can be made smaller due to the absence of the intermediate magnetic pole plate, and the device can be made smaller.

Furthermore, by changing the position and strength of the permanent magnet 14,
Optimal conditions for applying a magnetic field can be achieved relatively easily.

In this embodiment, a case has been described in which a permanent magnet is used as the auxiliary magnetic field generating device, but an electromagnetic coil may be used as the auxiliary magnetic field generating device.

〔Effect of the invention〕

As described above, according to the present invention, an auxiliary magnetic field generating device is provided that generates a magnetic field substantially parallel to the magnetic field generated by the main magnetic field generating device of the magnetic film forming apparatus.

It is possible to generate a uniform magnetic field parallel to the substrate surface over a wide range of the substrate holder, and a magnetic thin film with excellent magnetic properties can be formed on the substrate using a small device.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a longitudinal cross-sectional view showing an embodiment of the magnetic film forming apparatus according to the present invention, FIG. 2 is a cross-sectional view of FIG. 1, and FIG. 3 is a magnetic field line according to the present embodiment. FIG. 4 is a plan view showing lines of magnetic force produced by a conventional magnetic film forming apparatus. 1... Coil (main magnetic field generator), 2... Lines of magnetic force,
3... Substrate holder, 6... Substrate, 7... Vacuum container, 10... Target, 14... Permanent magnet (auxiliary 1
11 field generator).

Claims (1)

[Claims] 1. A target made of a film-forming material, a substrate that is a base material to be film-formed, a substrate holder that holds this substrate, and a main magnetic field generating device that applies a magnetic field onto the surface of the substrate; A magnetic film forming apparatus comprising a vacuum container that houses and holds at least a portion of these, characterized in that an auxiliary magnetic field generating device is provided that generates a magnetic field substantially parallel to the magnetic field generated by the main magnetic field generating device. Film forming device. 2. A magnetic film forming apparatus according to claim 1, wherein the auxiliary magnetic field generating device is a pair of permanent magnets provided substantially parallel to the substrate.